1 // SPDX-License-Identifier: GPL-2.0-or-later
3 Copyright (C) 2002 Richard Henderson
4 Copyright (C) 2001 Rusty Russell, 2002, 2010 Rusty Russell IBM.
7 #include <linux/export.h>
8 #include <linux/extable.h>
9 #include <linux/moduleloader.h>
10 #include <linux/trace_events.h>
11 #include <linux/init.h>
12 #include <linux/kallsyms.h>
13 #include <linux/file.h>
15 #include <linux/sysfs.h>
16 #include <linux/kernel.h>
17 #include <linux/slab.h>
18 #include <linux/vmalloc.h>
19 #include <linux/elf.h>
20 #include <linux/proc_fs.h>
21 #include <linux/security.h>
22 #include <linux/seq_file.h>
23 #include <linux/syscalls.h>
24 #include <linux/fcntl.h>
25 #include <linux/rcupdate.h>
26 #include <linux/capability.h>
27 #include <linux/cpu.h>
28 #include <linux/moduleparam.h>
29 #include <linux/errno.h>
30 #include <linux/err.h>
31 #include <linux/vermagic.h>
32 #include <linux/notifier.h>
33 #include <linux/sched.h>
34 #include <linux/device.h>
35 #include <linux/string.h>
36 #include <linux/mutex.h>
37 #include <linux/rculist.h>
38 #include <linux/uaccess.h>
39 #include <asm/cacheflush.h>
40 #include <linux/set_memory.h>
41 #include <asm/mmu_context.h>
42 #include <linux/license.h>
43 #include <asm/sections.h>
44 #include <linux/tracepoint.h>
45 #include <linux/ftrace.h>
46 #include <linux/livepatch.h>
47 #include <linux/async.h>
48 #include <linux/percpu.h>
49 #include <linux/kmemleak.h>
50 #include <linux/jump_label.h>
51 #include <linux/pfn.h>
52 #include <linux/bsearch.h>
53 #include <linux/dynamic_debug.h>
54 #include <linux/audit.h>
55 #include <uapi/linux/module.h>
56 #include "module-internal.h"
58 #define CREATE_TRACE_POINTS
59 #include <trace/events/module.h>
61 #ifndef ARCH_SHF_SMALL
62 #define ARCH_SHF_SMALL 0
66 * Modules' sections will be aligned on page boundaries
67 * to ensure complete separation of code and data, but
68 * only when CONFIG_ARCH_HAS_STRICT_MODULE_RWX=y
70 #ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX
71 # define debug_align(X) ALIGN(X, PAGE_SIZE)
73 # define debug_align(X) (X)
76 /* If this is set, the section belongs in the init part of the module */
77 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
81 * 1) List of modules (also safely readable with preempt_disable),
82 * 2) module_use links,
83 * 3) module_addr_min/module_addr_max.
84 * (delete and add uses RCU list operations). */
85 DEFINE_MUTEX(module_mutex
);
86 EXPORT_SYMBOL_GPL(module_mutex
);
87 static LIST_HEAD(modules
);
89 /* Work queue for freeing init sections in success case */
90 static struct work_struct init_free_wq
;
91 static struct llist_head init_free_list
;
93 #ifdef CONFIG_MODULES_TREE_LOOKUP
96 * Use a latched RB-tree for __module_address(); this allows us to use
97 * RCU-sched lookups of the address from any context.
99 * This is conditional on PERF_EVENTS || TRACING because those can really hit
100 * __module_address() hard by doing a lot of stack unwinding; potentially from
104 static __always_inline
unsigned long __mod_tree_val(struct latch_tree_node
*n
)
106 struct module_layout
*layout
= container_of(n
, struct module_layout
, mtn
.node
);
108 return (unsigned long)layout
->base
;
111 static __always_inline
unsigned long __mod_tree_size(struct latch_tree_node
*n
)
113 struct module_layout
*layout
= container_of(n
, struct module_layout
, mtn
.node
);
115 return (unsigned long)layout
->size
;
118 static __always_inline
bool
119 mod_tree_less(struct latch_tree_node
*a
, struct latch_tree_node
*b
)
121 return __mod_tree_val(a
) < __mod_tree_val(b
);
124 static __always_inline
int
125 mod_tree_comp(void *key
, struct latch_tree_node
*n
)
127 unsigned long val
= (unsigned long)key
;
128 unsigned long start
, end
;
130 start
= __mod_tree_val(n
);
134 end
= start
+ __mod_tree_size(n
);
141 static const struct latch_tree_ops mod_tree_ops
= {
142 .less
= mod_tree_less
,
143 .comp
= mod_tree_comp
,
146 static struct mod_tree_root
{
147 struct latch_tree_root root
;
148 unsigned long addr_min
;
149 unsigned long addr_max
;
150 } mod_tree __cacheline_aligned
= {
154 #define module_addr_min mod_tree.addr_min
155 #define module_addr_max mod_tree.addr_max
157 static noinline
void __mod_tree_insert(struct mod_tree_node
*node
)
159 latch_tree_insert(&node
->node
, &mod_tree
.root
, &mod_tree_ops
);
162 static void __mod_tree_remove(struct mod_tree_node
*node
)
164 latch_tree_erase(&node
->node
, &mod_tree
.root
, &mod_tree_ops
);
168 * These modifications: insert, remove_init and remove; are serialized by the
171 static void mod_tree_insert(struct module
*mod
)
173 mod
->core_layout
.mtn
.mod
= mod
;
174 mod
->init_layout
.mtn
.mod
= mod
;
176 __mod_tree_insert(&mod
->core_layout
.mtn
);
177 if (mod
->init_layout
.size
)
178 __mod_tree_insert(&mod
->init_layout
.mtn
);
181 static void mod_tree_remove_init(struct module
*mod
)
183 if (mod
->init_layout
.size
)
184 __mod_tree_remove(&mod
->init_layout
.mtn
);
187 static void mod_tree_remove(struct module
*mod
)
189 __mod_tree_remove(&mod
->core_layout
.mtn
);
190 mod_tree_remove_init(mod
);
193 static struct module
*mod_find(unsigned long addr
)
195 struct latch_tree_node
*ltn
;
197 ltn
= latch_tree_find((void *)addr
, &mod_tree
.root
, &mod_tree_ops
);
201 return container_of(ltn
, struct mod_tree_node
, node
)->mod
;
204 #else /* MODULES_TREE_LOOKUP */
206 static unsigned long module_addr_min
= -1UL, module_addr_max
= 0;
208 static void mod_tree_insert(struct module
*mod
) { }
209 static void mod_tree_remove_init(struct module
*mod
) { }
210 static void mod_tree_remove(struct module
*mod
) { }
212 static struct module
*mod_find(unsigned long addr
)
216 list_for_each_entry_rcu(mod
, &modules
, list
) {
217 if (within_module(addr
, mod
))
224 #endif /* MODULES_TREE_LOOKUP */
227 * Bounds of module text, for speeding up __module_address.
228 * Protected by module_mutex.
230 static void __mod_update_bounds(void *base
, unsigned int size
)
232 unsigned long min
= (unsigned long)base
;
233 unsigned long max
= min
+ size
;
235 if (min
< module_addr_min
)
236 module_addr_min
= min
;
237 if (max
> module_addr_max
)
238 module_addr_max
= max
;
241 static void mod_update_bounds(struct module
*mod
)
243 __mod_update_bounds(mod
->core_layout
.base
, mod
->core_layout
.size
);
244 if (mod
->init_layout
.size
)
245 __mod_update_bounds(mod
->init_layout
.base
, mod
->init_layout
.size
);
248 #ifdef CONFIG_KGDB_KDB
249 struct list_head
*kdb_modules
= &modules
; /* kdb needs the list of modules */
250 #endif /* CONFIG_KGDB_KDB */
252 static void module_assert_mutex(void)
254 lockdep_assert_held(&module_mutex
);
257 static void module_assert_mutex_or_preempt(void)
259 #ifdef CONFIG_LOCKDEP
260 if (unlikely(!debug_locks
))
263 WARN_ON_ONCE(!rcu_read_lock_sched_held() &&
264 !lockdep_is_held(&module_mutex
));
268 static bool sig_enforce
= IS_ENABLED(CONFIG_MODULE_SIG_FORCE
);
269 module_param(sig_enforce
, bool_enable_only
, 0644);
272 * Export sig_enforce kernel cmdline parameter to allow other subsystems rely
273 * on that instead of directly to CONFIG_MODULE_SIG_FORCE config.
275 bool is_module_sig_enforced(void)
279 EXPORT_SYMBOL(is_module_sig_enforced
);
281 void set_module_sig_enforced(void)
286 /* Block module loading/unloading? */
287 int modules_disabled
= 0;
288 core_param(nomodule
, modules_disabled
, bint
, 0);
290 /* Waiting for a module to finish initializing? */
291 static DECLARE_WAIT_QUEUE_HEAD(module_wq
);
293 static BLOCKING_NOTIFIER_HEAD(module_notify_list
);
295 int register_module_notifier(struct notifier_block
*nb
)
297 return blocking_notifier_chain_register(&module_notify_list
, nb
);
299 EXPORT_SYMBOL(register_module_notifier
);
301 int unregister_module_notifier(struct notifier_block
*nb
)
303 return blocking_notifier_chain_unregister(&module_notify_list
, nb
);
305 EXPORT_SYMBOL(unregister_module_notifier
);
308 * We require a truly strong try_module_get(): 0 means success.
309 * Otherwise an error is returned due to ongoing or failed
310 * initialization etc.
312 static inline int strong_try_module_get(struct module
*mod
)
314 BUG_ON(mod
&& mod
->state
== MODULE_STATE_UNFORMED
);
315 if (mod
&& mod
->state
== MODULE_STATE_COMING
)
317 if (try_module_get(mod
))
323 static inline void add_taint_module(struct module
*mod
, unsigned flag
,
324 enum lockdep_ok lockdep_ok
)
326 add_taint(flag
, lockdep_ok
);
327 set_bit(flag
, &mod
->taints
);
331 * A thread that wants to hold a reference to a module only while it
332 * is running can call this to safely exit. nfsd and lockd use this.
334 void __noreturn
__module_put_and_exit(struct module
*mod
, long code
)
339 EXPORT_SYMBOL(__module_put_and_exit
);
341 /* Find a module section: 0 means not found. */
342 static unsigned int find_sec(const struct load_info
*info
, const char *name
)
346 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
347 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
348 /* Alloc bit cleared means "ignore it." */
349 if ((shdr
->sh_flags
& SHF_ALLOC
)
350 && strcmp(info
->secstrings
+ shdr
->sh_name
, name
) == 0)
356 /* Find a module section, or NULL. */
357 static void *section_addr(const struct load_info
*info
, const char *name
)
359 /* Section 0 has sh_addr 0. */
360 return (void *)info
->sechdrs
[find_sec(info
, name
)].sh_addr
;
363 /* Find a module section, or NULL. Fill in number of "objects" in section. */
364 static void *section_objs(const struct load_info
*info
,
369 unsigned int sec
= find_sec(info
, name
);
371 /* Section 0 has sh_addr 0 and sh_size 0. */
372 *num
= info
->sechdrs
[sec
].sh_size
/ object_size
;
373 return (void *)info
->sechdrs
[sec
].sh_addr
;
376 /* Provided by the linker */
377 extern const struct kernel_symbol __start___ksymtab
[];
378 extern const struct kernel_symbol __stop___ksymtab
[];
379 extern const struct kernel_symbol __start___ksymtab_gpl
[];
380 extern const struct kernel_symbol __stop___ksymtab_gpl
[];
381 extern const struct kernel_symbol __start___ksymtab_gpl_future
[];
382 extern const struct kernel_symbol __stop___ksymtab_gpl_future
[];
383 extern const s32 __start___kcrctab
[];
384 extern const s32 __start___kcrctab_gpl
[];
385 extern const s32 __start___kcrctab_gpl_future
[];
386 #ifdef CONFIG_UNUSED_SYMBOLS
387 extern const struct kernel_symbol __start___ksymtab_unused
[];
388 extern const struct kernel_symbol __stop___ksymtab_unused
[];
389 extern const struct kernel_symbol __start___ksymtab_unused_gpl
[];
390 extern const struct kernel_symbol __stop___ksymtab_unused_gpl
[];
391 extern const s32 __start___kcrctab_unused
[];
392 extern const s32 __start___kcrctab_unused_gpl
[];
395 #ifndef CONFIG_MODVERSIONS
396 #define symversion(base, idx) NULL
398 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
401 static bool each_symbol_in_section(const struct symsearch
*arr
,
402 unsigned int arrsize
,
403 struct module
*owner
,
404 bool (*fn
)(const struct symsearch
*syms
,
405 struct module
*owner
,
411 for (j
= 0; j
< arrsize
; j
++) {
412 if (fn(&arr
[j
], owner
, data
))
419 /* Returns true as soon as fn returns true, otherwise false. */
420 bool each_symbol_section(bool (*fn
)(const struct symsearch
*arr
,
421 struct module
*owner
,
426 static const struct symsearch arr
[] = {
427 { __start___ksymtab
, __stop___ksymtab
, __start___kcrctab
,
428 NOT_GPL_ONLY
, false },
429 { __start___ksymtab_gpl
, __stop___ksymtab_gpl
,
430 __start___kcrctab_gpl
,
432 { __start___ksymtab_gpl_future
, __stop___ksymtab_gpl_future
,
433 __start___kcrctab_gpl_future
,
434 WILL_BE_GPL_ONLY
, false },
435 #ifdef CONFIG_UNUSED_SYMBOLS
436 { __start___ksymtab_unused
, __stop___ksymtab_unused
,
437 __start___kcrctab_unused
,
438 NOT_GPL_ONLY
, true },
439 { __start___ksymtab_unused_gpl
, __stop___ksymtab_unused_gpl
,
440 __start___kcrctab_unused_gpl
,
445 module_assert_mutex_or_preempt();
447 if (each_symbol_in_section(arr
, ARRAY_SIZE(arr
), NULL
, fn
, data
))
450 list_for_each_entry_rcu(mod
, &modules
, list
) {
451 struct symsearch arr
[] = {
452 { mod
->syms
, mod
->syms
+ mod
->num_syms
, mod
->crcs
,
453 NOT_GPL_ONLY
, false },
454 { mod
->gpl_syms
, mod
->gpl_syms
+ mod
->num_gpl_syms
,
457 { mod
->gpl_future_syms
,
458 mod
->gpl_future_syms
+ mod
->num_gpl_future_syms
,
459 mod
->gpl_future_crcs
,
460 WILL_BE_GPL_ONLY
, false },
461 #ifdef CONFIG_UNUSED_SYMBOLS
463 mod
->unused_syms
+ mod
->num_unused_syms
,
465 NOT_GPL_ONLY
, true },
466 { mod
->unused_gpl_syms
,
467 mod
->unused_gpl_syms
+ mod
->num_unused_gpl_syms
,
468 mod
->unused_gpl_crcs
,
473 if (mod
->state
== MODULE_STATE_UNFORMED
)
476 if (each_symbol_in_section(arr
, ARRAY_SIZE(arr
), mod
, fn
, data
))
481 EXPORT_SYMBOL_GPL(each_symbol_section
);
483 struct find_symbol_arg
{
490 struct module
*owner
;
492 const struct kernel_symbol
*sym
;
495 static bool check_exported_symbol(const struct symsearch
*syms
,
496 struct module
*owner
,
497 unsigned int symnum
, void *data
)
499 struct find_symbol_arg
*fsa
= data
;
502 if (syms
->licence
== GPL_ONLY
)
504 if (syms
->licence
== WILL_BE_GPL_ONLY
&& fsa
->warn
) {
505 pr_warn("Symbol %s is being used by a non-GPL module, "
506 "which will not be allowed in the future\n",
511 #ifdef CONFIG_UNUSED_SYMBOLS
512 if (syms
->unused
&& fsa
->warn
) {
513 pr_warn("Symbol %s is marked as UNUSED, however this module is "
514 "using it.\n", fsa
->name
);
515 pr_warn("This symbol will go away in the future.\n");
516 pr_warn("Please evaluate if this is the right api to use and "
517 "if it really is, submit a report to the linux kernel "
518 "mailing list together with submitting your code for "
524 fsa
->crc
= symversion(syms
->crcs
, symnum
);
525 fsa
->sym
= &syms
->start
[symnum
];
529 static unsigned long kernel_symbol_value(const struct kernel_symbol
*sym
)
531 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
532 return (unsigned long)offset_to_ptr(&sym
->value_offset
);
538 static const char *kernel_symbol_name(const struct kernel_symbol
*sym
)
540 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
541 return offset_to_ptr(&sym
->name_offset
);
547 static int cmp_name(const void *va
, const void *vb
)
550 const struct kernel_symbol
*b
;
552 return strcmp(a
, kernel_symbol_name(b
));
555 static bool find_exported_symbol_in_section(const struct symsearch
*syms
,
556 struct module
*owner
,
559 struct find_symbol_arg
*fsa
= data
;
560 struct kernel_symbol
*sym
;
562 sym
= bsearch(fsa
->name
, syms
->start
, syms
->stop
- syms
->start
,
563 sizeof(struct kernel_symbol
), cmp_name
);
565 if (sym
!= NULL
&& check_exported_symbol(syms
, owner
,
566 sym
- syms
->start
, data
))
572 /* Find an exported symbol and return it, along with, (optional) crc and
573 * (optional) module which owns it. Needs preempt disabled or module_mutex. */
574 const struct kernel_symbol
*find_symbol(const char *name
,
575 struct module
**owner
,
580 struct find_symbol_arg fsa
;
586 if (each_symbol_section(find_exported_symbol_in_section
, &fsa
)) {
594 pr_debug("Failed to find symbol %s\n", name
);
597 EXPORT_SYMBOL_GPL(find_symbol
);
600 * Search for module by name: must hold module_mutex (or preempt disabled
601 * for read-only access).
603 static struct module
*find_module_all(const char *name
, size_t len
,
608 module_assert_mutex_or_preempt();
610 list_for_each_entry_rcu(mod
, &modules
, list
) {
611 if (!even_unformed
&& mod
->state
== MODULE_STATE_UNFORMED
)
613 if (strlen(mod
->name
) == len
&& !memcmp(mod
->name
, name
, len
))
619 struct module
*find_module(const char *name
)
621 module_assert_mutex();
622 return find_module_all(name
, strlen(name
), false);
624 EXPORT_SYMBOL_GPL(find_module
);
628 static inline void __percpu
*mod_percpu(struct module
*mod
)
633 static int percpu_modalloc(struct module
*mod
, struct load_info
*info
)
635 Elf_Shdr
*pcpusec
= &info
->sechdrs
[info
->index
.pcpu
];
636 unsigned long align
= pcpusec
->sh_addralign
;
638 if (!pcpusec
->sh_size
)
641 if (align
> PAGE_SIZE
) {
642 pr_warn("%s: per-cpu alignment %li > %li\n",
643 mod
->name
, align
, PAGE_SIZE
);
647 mod
->percpu
= __alloc_reserved_percpu(pcpusec
->sh_size
, align
);
649 pr_warn("%s: Could not allocate %lu bytes percpu data\n",
650 mod
->name
, (unsigned long)pcpusec
->sh_size
);
653 mod
->percpu_size
= pcpusec
->sh_size
;
657 static void percpu_modfree(struct module
*mod
)
659 free_percpu(mod
->percpu
);
662 static unsigned int find_pcpusec(struct load_info
*info
)
664 return find_sec(info
, ".data..percpu");
667 static void percpu_modcopy(struct module
*mod
,
668 const void *from
, unsigned long size
)
672 for_each_possible_cpu(cpu
)
673 memcpy(per_cpu_ptr(mod
->percpu
, cpu
), from
, size
);
676 bool __is_module_percpu_address(unsigned long addr
, unsigned long *can_addr
)
683 list_for_each_entry_rcu(mod
, &modules
, list
) {
684 if (mod
->state
== MODULE_STATE_UNFORMED
)
686 if (!mod
->percpu_size
)
688 for_each_possible_cpu(cpu
) {
689 void *start
= per_cpu_ptr(mod
->percpu
, cpu
);
690 void *va
= (void *)addr
;
692 if (va
>= start
&& va
< start
+ mod
->percpu_size
) {
694 *can_addr
= (unsigned long) (va
- start
);
695 *can_addr
+= (unsigned long)
696 per_cpu_ptr(mod
->percpu
,
710 * is_module_percpu_address - test whether address is from module static percpu
711 * @addr: address to test
713 * Test whether @addr belongs to module static percpu area.
716 * %true if @addr is from module static percpu area
718 bool is_module_percpu_address(unsigned long addr
)
720 return __is_module_percpu_address(addr
, NULL
);
723 #else /* ... !CONFIG_SMP */
725 static inline void __percpu
*mod_percpu(struct module
*mod
)
729 static int percpu_modalloc(struct module
*mod
, struct load_info
*info
)
731 /* UP modules shouldn't have this section: ENOMEM isn't quite right */
732 if (info
->sechdrs
[info
->index
.pcpu
].sh_size
!= 0)
736 static inline void percpu_modfree(struct module
*mod
)
739 static unsigned int find_pcpusec(struct load_info
*info
)
743 static inline void percpu_modcopy(struct module
*mod
,
744 const void *from
, unsigned long size
)
746 /* pcpusec should be 0, and size of that section should be 0. */
749 bool is_module_percpu_address(unsigned long addr
)
754 bool __is_module_percpu_address(unsigned long addr
, unsigned long *can_addr
)
759 #endif /* CONFIG_SMP */
761 #define MODINFO_ATTR(field) \
762 static void setup_modinfo_##field(struct module *mod, const char *s) \
764 mod->field = kstrdup(s, GFP_KERNEL); \
766 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
767 struct module_kobject *mk, char *buffer) \
769 return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \
771 static int modinfo_##field##_exists(struct module *mod) \
773 return mod->field != NULL; \
775 static void free_modinfo_##field(struct module *mod) \
780 static struct module_attribute modinfo_##field = { \
781 .attr = { .name = __stringify(field), .mode = 0444 }, \
782 .show = show_modinfo_##field, \
783 .setup = setup_modinfo_##field, \
784 .test = modinfo_##field##_exists, \
785 .free = free_modinfo_##field, \
788 MODINFO_ATTR(version
);
789 MODINFO_ATTR(srcversion
);
791 static char last_unloaded_module
[MODULE_NAME_LEN
+1];
793 #ifdef CONFIG_MODULE_UNLOAD
795 EXPORT_TRACEPOINT_SYMBOL(module_get
);
797 /* MODULE_REF_BASE is the base reference count by kmodule loader. */
798 #define MODULE_REF_BASE 1
800 /* Init the unload section of the module. */
801 static int module_unload_init(struct module
*mod
)
804 * Initialize reference counter to MODULE_REF_BASE.
805 * refcnt == 0 means module is going.
807 atomic_set(&mod
->refcnt
, MODULE_REF_BASE
);
809 INIT_LIST_HEAD(&mod
->source_list
);
810 INIT_LIST_HEAD(&mod
->target_list
);
812 /* Hold reference count during initialization. */
813 atomic_inc(&mod
->refcnt
);
818 /* Does a already use b? */
819 static int already_uses(struct module
*a
, struct module
*b
)
821 struct module_use
*use
;
823 list_for_each_entry(use
, &b
->source_list
, source_list
) {
824 if (use
->source
== a
) {
825 pr_debug("%s uses %s!\n", a
->name
, b
->name
);
829 pr_debug("%s does not use %s!\n", a
->name
, b
->name
);
835 * - we add 'a' as a "source", 'b' as a "target" of module use
836 * - the module_use is added to the list of 'b' sources (so
837 * 'b' can walk the list to see who sourced them), and of 'a'
838 * targets (so 'a' can see what modules it targets).
840 static int add_module_usage(struct module
*a
, struct module
*b
)
842 struct module_use
*use
;
844 pr_debug("Allocating new usage for %s.\n", a
->name
);
845 use
= kmalloc(sizeof(*use
), GFP_ATOMIC
);
851 list_add(&use
->source_list
, &b
->source_list
);
852 list_add(&use
->target_list
, &a
->target_list
);
856 /* Module a uses b: caller needs module_mutex() */
857 int ref_module(struct module
*a
, struct module
*b
)
861 if (b
== NULL
|| already_uses(a
, b
))
864 /* If module isn't available, we fail. */
865 err
= strong_try_module_get(b
);
869 err
= add_module_usage(a
, b
);
876 EXPORT_SYMBOL_GPL(ref_module
);
878 /* Clear the unload stuff of the module. */
879 static void module_unload_free(struct module
*mod
)
881 struct module_use
*use
, *tmp
;
883 mutex_lock(&module_mutex
);
884 list_for_each_entry_safe(use
, tmp
, &mod
->target_list
, target_list
) {
885 struct module
*i
= use
->target
;
886 pr_debug("%s unusing %s\n", mod
->name
, i
->name
);
888 list_del(&use
->source_list
);
889 list_del(&use
->target_list
);
892 mutex_unlock(&module_mutex
);
895 #ifdef CONFIG_MODULE_FORCE_UNLOAD
896 static inline int try_force_unload(unsigned int flags
)
898 int ret
= (flags
& O_TRUNC
);
900 add_taint(TAINT_FORCED_RMMOD
, LOCKDEP_NOW_UNRELIABLE
);
904 static inline int try_force_unload(unsigned int flags
)
908 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
910 /* Try to release refcount of module, 0 means success. */
911 static int try_release_module_ref(struct module
*mod
)
915 /* Try to decrement refcnt which we set at loading */
916 ret
= atomic_sub_return(MODULE_REF_BASE
, &mod
->refcnt
);
919 /* Someone can put this right now, recover with checking */
920 ret
= atomic_add_unless(&mod
->refcnt
, MODULE_REF_BASE
, 0);
925 static int try_stop_module(struct module
*mod
, int flags
, int *forced
)
927 /* If it's not unused, quit unless we're forcing. */
928 if (try_release_module_ref(mod
) != 0) {
929 *forced
= try_force_unload(flags
);
934 /* Mark it as dying. */
935 mod
->state
= MODULE_STATE_GOING
;
941 * module_refcount - return the refcount or -1 if unloading
943 * @mod: the module we're checking
946 * -1 if the module is in the process of unloading
947 * otherwise the number of references in the kernel to the module
949 int module_refcount(struct module
*mod
)
951 return atomic_read(&mod
->refcnt
) - MODULE_REF_BASE
;
953 EXPORT_SYMBOL(module_refcount
);
955 /* This exists whether we can unload or not */
956 static void free_module(struct module
*mod
);
958 SYSCALL_DEFINE2(delete_module
, const char __user
*, name_user
,
962 char name
[MODULE_NAME_LEN
];
965 if (!capable(CAP_SYS_MODULE
) || modules_disabled
)
968 if (strncpy_from_user(name
, name_user
, MODULE_NAME_LEN
-1) < 0)
970 name
[MODULE_NAME_LEN
-1] = '\0';
972 audit_log_kern_module(name
);
974 if (mutex_lock_interruptible(&module_mutex
) != 0)
977 mod
= find_module(name
);
983 if (!list_empty(&mod
->source_list
)) {
984 /* Other modules depend on us: get rid of them first. */
989 /* Doing init or already dying? */
990 if (mod
->state
!= MODULE_STATE_LIVE
) {
991 /* FIXME: if (force), slam module count damn the torpedoes */
992 pr_debug("%s already dying\n", mod
->name
);
997 /* If it has an init func, it must have an exit func to unload */
998 if (mod
->init
&& !mod
->exit
) {
999 forced
= try_force_unload(flags
);
1001 /* This module can't be removed */
1007 /* Stop the machine so refcounts can't move and disable module. */
1008 ret
= try_stop_module(mod
, flags
, &forced
);
1012 mutex_unlock(&module_mutex
);
1013 /* Final destruction now no one is using it. */
1014 if (mod
->exit
!= NULL
)
1016 blocking_notifier_call_chain(&module_notify_list
,
1017 MODULE_STATE_GOING
, mod
);
1018 klp_module_going(mod
);
1019 ftrace_release_mod(mod
);
1021 async_synchronize_full();
1023 /* Store the name of the last unloaded module for diagnostic purposes */
1024 strlcpy(last_unloaded_module
, mod
->name
, sizeof(last_unloaded_module
));
1029 mutex_unlock(&module_mutex
);
1033 static inline void print_unload_info(struct seq_file
*m
, struct module
*mod
)
1035 struct module_use
*use
;
1036 int printed_something
= 0;
1038 seq_printf(m
, " %i ", module_refcount(mod
));
1041 * Always include a trailing , so userspace can differentiate
1042 * between this and the old multi-field proc format.
1044 list_for_each_entry(use
, &mod
->source_list
, source_list
) {
1045 printed_something
= 1;
1046 seq_printf(m
, "%s,", use
->source
->name
);
1049 if (mod
->init
!= NULL
&& mod
->exit
== NULL
) {
1050 printed_something
= 1;
1051 seq_puts(m
, "[permanent],");
1054 if (!printed_something
)
1058 void __symbol_put(const char *symbol
)
1060 struct module
*owner
;
1063 if (!find_symbol(symbol
, &owner
, NULL
, true, false))
1068 EXPORT_SYMBOL(__symbol_put
);
1070 /* Note this assumes addr is a function, which it currently always is. */
1071 void symbol_put_addr(void *addr
)
1073 struct module
*modaddr
;
1074 unsigned long a
= (unsigned long)dereference_function_descriptor(addr
);
1076 if (core_kernel_text(a
))
1080 * Even though we hold a reference on the module; we still need to
1081 * disable preemption in order to safely traverse the data structure.
1084 modaddr
= __module_text_address(a
);
1086 module_put(modaddr
);
1089 EXPORT_SYMBOL_GPL(symbol_put_addr
);
1091 static ssize_t
show_refcnt(struct module_attribute
*mattr
,
1092 struct module_kobject
*mk
, char *buffer
)
1094 return sprintf(buffer
, "%i\n", module_refcount(mk
->mod
));
1097 static struct module_attribute modinfo_refcnt
=
1098 __ATTR(refcnt
, 0444, show_refcnt
, NULL
);
1100 void __module_get(struct module
*module
)
1104 atomic_inc(&module
->refcnt
);
1105 trace_module_get(module
, _RET_IP_
);
1109 EXPORT_SYMBOL(__module_get
);
1111 bool try_module_get(struct module
*module
)
1117 /* Note: here, we can fail to get a reference */
1118 if (likely(module_is_live(module
) &&
1119 atomic_inc_not_zero(&module
->refcnt
) != 0))
1120 trace_module_get(module
, _RET_IP_
);
1128 EXPORT_SYMBOL(try_module_get
);
1130 void module_put(struct module
*module
)
1136 ret
= atomic_dec_if_positive(&module
->refcnt
);
1137 WARN_ON(ret
< 0); /* Failed to put refcount */
1138 trace_module_put(module
, _RET_IP_
);
1142 EXPORT_SYMBOL(module_put
);
1144 #else /* !CONFIG_MODULE_UNLOAD */
1145 static inline void print_unload_info(struct seq_file
*m
, struct module
*mod
)
1147 /* We don't know the usage count, or what modules are using. */
1148 seq_puts(m
, " - -");
1151 static inline void module_unload_free(struct module
*mod
)
1155 int ref_module(struct module
*a
, struct module
*b
)
1157 return strong_try_module_get(b
);
1159 EXPORT_SYMBOL_GPL(ref_module
);
1161 static inline int module_unload_init(struct module
*mod
)
1165 #endif /* CONFIG_MODULE_UNLOAD */
1167 static size_t module_flags_taint(struct module
*mod
, char *buf
)
1172 for (i
= 0; i
< TAINT_FLAGS_COUNT
; i
++) {
1173 if (taint_flags
[i
].module
&& test_bit(i
, &mod
->taints
))
1174 buf
[l
++] = taint_flags
[i
].c_true
;
1180 static ssize_t
show_initstate(struct module_attribute
*mattr
,
1181 struct module_kobject
*mk
, char *buffer
)
1183 const char *state
= "unknown";
1185 switch (mk
->mod
->state
) {
1186 case MODULE_STATE_LIVE
:
1189 case MODULE_STATE_COMING
:
1192 case MODULE_STATE_GOING
:
1198 return sprintf(buffer
, "%s\n", state
);
1201 static struct module_attribute modinfo_initstate
=
1202 __ATTR(initstate
, 0444, show_initstate
, NULL
);
1204 static ssize_t
store_uevent(struct module_attribute
*mattr
,
1205 struct module_kobject
*mk
,
1206 const char *buffer
, size_t count
)
1210 rc
= kobject_synth_uevent(&mk
->kobj
, buffer
, count
);
1211 return rc
? rc
: count
;
1214 struct module_attribute module_uevent
=
1215 __ATTR(uevent
, 0200, NULL
, store_uevent
);
1217 static ssize_t
show_coresize(struct module_attribute
*mattr
,
1218 struct module_kobject
*mk
, char *buffer
)
1220 return sprintf(buffer
, "%u\n", mk
->mod
->core_layout
.size
);
1223 static struct module_attribute modinfo_coresize
=
1224 __ATTR(coresize
, 0444, show_coresize
, NULL
);
1226 static ssize_t
show_initsize(struct module_attribute
*mattr
,
1227 struct module_kobject
*mk
, char *buffer
)
1229 return sprintf(buffer
, "%u\n", mk
->mod
->init_layout
.size
);
1232 static struct module_attribute modinfo_initsize
=
1233 __ATTR(initsize
, 0444, show_initsize
, NULL
);
1235 static ssize_t
show_taint(struct module_attribute
*mattr
,
1236 struct module_kobject
*mk
, char *buffer
)
1240 l
= module_flags_taint(mk
->mod
, buffer
);
1245 static struct module_attribute modinfo_taint
=
1246 __ATTR(taint
, 0444, show_taint
, NULL
);
1248 static struct module_attribute
*modinfo_attrs
[] = {
1251 &modinfo_srcversion
,
1256 #ifdef CONFIG_MODULE_UNLOAD
1262 static const char vermagic
[] = VERMAGIC_STRING
;
1264 static int try_to_force_load(struct module
*mod
, const char *reason
)
1266 #ifdef CONFIG_MODULE_FORCE_LOAD
1267 if (!test_taint(TAINT_FORCED_MODULE
))
1268 pr_warn("%s: %s: kernel tainted.\n", mod
->name
, reason
);
1269 add_taint_module(mod
, TAINT_FORCED_MODULE
, LOCKDEP_NOW_UNRELIABLE
);
1276 #ifdef CONFIG_MODVERSIONS
1278 static u32
resolve_rel_crc(const s32
*crc
)
1280 return *(u32
*)((void *)crc
+ *crc
);
1283 static int check_version(const struct load_info
*info
,
1284 const char *symname
,
1288 Elf_Shdr
*sechdrs
= info
->sechdrs
;
1289 unsigned int versindex
= info
->index
.vers
;
1290 unsigned int i
, num_versions
;
1291 struct modversion_info
*versions
;
1293 /* Exporting module didn't supply crcs? OK, we're already tainted. */
1297 /* No versions at all? modprobe --force does this. */
1299 return try_to_force_load(mod
, symname
) == 0;
1301 versions
= (void *) sechdrs
[versindex
].sh_addr
;
1302 num_versions
= sechdrs
[versindex
].sh_size
1303 / sizeof(struct modversion_info
);
1305 for (i
= 0; i
< num_versions
; i
++) {
1308 if (strcmp(versions
[i
].name
, symname
) != 0)
1311 if (IS_ENABLED(CONFIG_MODULE_REL_CRCS
))
1312 crcval
= resolve_rel_crc(crc
);
1315 if (versions
[i
].crc
== crcval
)
1317 pr_debug("Found checksum %X vs module %lX\n",
1318 crcval
, versions
[i
].crc
);
1322 /* Broken toolchain. Warn once, then let it go.. */
1323 pr_warn_once("%s: no symbol version for %s\n", info
->name
, symname
);
1327 pr_warn("%s: disagrees about version of symbol %s\n",
1328 info
->name
, symname
);
1332 static inline int check_modstruct_version(const struct load_info
*info
,
1338 * Since this should be found in kernel (which can't be removed), no
1339 * locking is necessary -- use preempt_disable() to placate lockdep.
1342 if (!find_symbol("module_layout", NULL
, &crc
, true, false)) {
1347 return check_version(info
, "module_layout", mod
, crc
);
1350 /* First part is kernel version, which we ignore if module has crcs. */
1351 static inline int same_magic(const char *amagic
, const char *bmagic
,
1355 amagic
+= strcspn(amagic
, " ");
1356 bmagic
+= strcspn(bmagic
, " ");
1358 return strcmp(amagic
, bmagic
) == 0;
1361 static inline int check_version(const struct load_info
*info
,
1362 const char *symname
,
1369 static inline int check_modstruct_version(const struct load_info
*info
,
1375 static inline int same_magic(const char *amagic
, const char *bmagic
,
1378 return strcmp(amagic
, bmagic
) == 0;
1380 #endif /* CONFIG_MODVERSIONS */
1382 /* Resolve a symbol for this module. I.e. if we find one, record usage. */
1383 static const struct kernel_symbol
*resolve_symbol(struct module
*mod
,
1384 const struct load_info
*info
,
1388 struct module
*owner
;
1389 const struct kernel_symbol
*sym
;
1394 * The module_mutex should not be a heavily contended lock;
1395 * if we get the occasional sleep here, we'll go an extra iteration
1396 * in the wait_event_interruptible(), which is harmless.
1398 sched_annotate_sleep();
1399 mutex_lock(&module_mutex
);
1400 sym
= find_symbol(name
, &owner
, &crc
,
1401 !(mod
->taints
& (1 << TAINT_PROPRIETARY_MODULE
)), true);
1405 if (!check_version(info
, name
, mod
, crc
)) {
1406 sym
= ERR_PTR(-EINVAL
);
1410 err
= ref_module(mod
, owner
);
1417 /* We must make copy under the lock if we failed to get ref. */
1418 strncpy(ownername
, module_name(owner
), MODULE_NAME_LEN
);
1420 mutex_unlock(&module_mutex
);
1424 static const struct kernel_symbol
*
1425 resolve_symbol_wait(struct module
*mod
,
1426 const struct load_info
*info
,
1429 const struct kernel_symbol
*ksym
;
1430 char owner
[MODULE_NAME_LEN
];
1432 if (wait_event_interruptible_timeout(module_wq
,
1433 !IS_ERR(ksym
= resolve_symbol(mod
, info
, name
, owner
))
1434 || PTR_ERR(ksym
) != -EBUSY
,
1436 pr_warn("%s: gave up waiting for init of module %s.\n",
1443 * /sys/module/foo/sections stuff
1444 * J. Corbet <corbet@lwn.net>
1448 #ifdef CONFIG_KALLSYMS
1449 static inline bool sect_empty(const Elf_Shdr
*sect
)
1451 return !(sect
->sh_flags
& SHF_ALLOC
) || sect
->sh_size
== 0;
1454 struct module_sect_attr
{
1455 struct module_attribute mattr
;
1457 unsigned long address
;
1460 struct module_sect_attrs
{
1461 struct attribute_group grp
;
1462 unsigned int nsections
;
1463 struct module_sect_attr attrs
[0];
1466 static ssize_t
module_sect_show(struct module_attribute
*mattr
,
1467 struct module_kobject
*mk
, char *buf
)
1469 struct module_sect_attr
*sattr
=
1470 container_of(mattr
, struct module_sect_attr
, mattr
);
1471 return sprintf(buf
, "0x%px\n", kptr_restrict
< 2 ?
1472 (void *)sattr
->address
: NULL
);
1475 static void free_sect_attrs(struct module_sect_attrs
*sect_attrs
)
1477 unsigned int section
;
1479 for (section
= 0; section
< sect_attrs
->nsections
; section
++)
1480 kfree(sect_attrs
->attrs
[section
].name
);
1484 static void add_sect_attrs(struct module
*mod
, const struct load_info
*info
)
1486 unsigned int nloaded
= 0, i
, size
[2];
1487 struct module_sect_attrs
*sect_attrs
;
1488 struct module_sect_attr
*sattr
;
1489 struct attribute
**gattr
;
1491 /* Count loaded sections and allocate structures */
1492 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
1493 if (!sect_empty(&info
->sechdrs
[i
]))
1495 size
[0] = ALIGN(struct_size(sect_attrs
, attrs
, nloaded
),
1496 sizeof(sect_attrs
->grp
.attrs
[0]));
1497 size
[1] = (nloaded
+ 1) * sizeof(sect_attrs
->grp
.attrs
[0]);
1498 sect_attrs
= kzalloc(size
[0] + size
[1], GFP_KERNEL
);
1499 if (sect_attrs
== NULL
)
1502 /* Setup section attributes. */
1503 sect_attrs
->grp
.name
= "sections";
1504 sect_attrs
->grp
.attrs
= (void *)sect_attrs
+ size
[0];
1506 sect_attrs
->nsections
= 0;
1507 sattr
= §_attrs
->attrs
[0];
1508 gattr
= §_attrs
->grp
.attrs
[0];
1509 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++) {
1510 Elf_Shdr
*sec
= &info
->sechdrs
[i
];
1511 if (sect_empty(sec
))
1513 sattr
->address
= sec
->sh_addr
;
1514 sattr
->name
= kstrdup(info
->secstrings
+ sec
->sh_name
,
1516 if (sattr
->name
== NULL
)
1518 sect_attrs
->nsections
++;
1519 sysfs_attr_init(&sattr
->mattr
.attr
);
1520 sattr
->mattr
.show
= module_sect_show
;
1521 sattr
->mattr
.store
= NULL
;
1522 sattr
->mattr
.attr
.name
= sattr
->name
;
1523 sattr
->mattr
.attr
.mode
= S_IRUSR
;
1524 *(gattr
++) = &(sattr
++)->mattr
.attr
;
1528 if (sysfs_create_group(&mod
->mkobj
.kobj
, §_attrs
->grp
))
1531 mod
->sect_attrs
= sect_attrs
;
1534 free_sect_attrs(sect_attrs
);
1537 static void remove_sect_attrs(struct module
*mod
)
1539 if (mod
->sect_attrs
) {
1540 sysfs_remove_group(&mod
->mkobj
.kobj
,
1541 &mod
->sect_attrs
->grp
);
1542 /* We are positive that no one is using any sect attrs
1543 * at this point. Deallocate immediately. */
1544 free_sect_attrs(mod
->sect_attrs
);
1545 mod
->sect_attrs
= NULL
;
1550 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1553 struct module_notes_attrs
{
1554 struct kobject
*dir
;
1556 struct bin_attribute attrs
[0];
1559 static ssize_t
module_notes_read(struct file
*filp
, struct kobject
*kobj
,
1560 struct bin_attribute
*bin_attr
,
1561 char *buf
, loff_t pos
, size_t count
)
1564 * The caller checked the pos and count against our size.
1566 memcpy(buf
, bin_attr
->private + pos
, count
);
1570 static void free_notes_attrs(struct module_notes_attrs
*notes_attrs
,
1573 if (notes_attrs
->dir
) {
1575 sysfs_remove_bin_file(notes_attrs
->dir
,
1576 ¬es_attrs
->attrs
[i
]);
1577 kobject_put(notes_attrs
->dir
);
1582 static void add_notes_attrs(struct module
*mod
, const struct load_info
*info
)
1584 unsigned int notes
, loaded
, i
;
1585 struct module_notes_attrs
*notes_attrs
;
1586 struct bin_attribute
*nattr
;
1588 /* failed to create section attributes, so can't create notes */
1589 if (!mod
->sect_attrs
)
1592 /* Count notes sections and allocate structures. */
1594 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
1595 if (!sect_empty(&info
->sechdrs
[i
]) &&
1596 (info
->sechdrs
[i
].sh_type
== SHT_NOTE
))
1602 notes_attrs
= kzalloc(struct_size(notes_attrs
, attrs
, notes
),
1604 if (notes_attrs
== NULL
)
1607 notes_attrs
->notes
= notes
;
1608 nattr
= ¬es_attrs
->attrs
[0];
1609 for (loaded
= i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
1610 if (sect_empty(&info
->sechdrs
[i
]))
1612 if (info
->sechdrs
[i
].sh_type
== SHT_NOTE
) {
1613 sysfs_bin_attr_init(nattr
);
1614 nattr
->attr
.name
= mod
->sect_attrs
->attrs
[loaded
].name
;
1615 nattr
->attr
.mode
= S_IRUGO
;
1616 nattr
->size
= info
->sechdrs
[i
].sh_size
;
1617 nattr
->private = (void *) info
->sechdrs
[i
].sh_addr
;
1618 nattr
->read
= module_notes_read
;
1624 notes_attrs
->dir
= kobject_create_and_add("notes", &mod
->mkobj
.kobj
);
1625 if (!notes_attrs
->dir
)
1628 for (i
= 0; i
< notes
; ++i
)
1629 if (sysfs_create_bin_file(notes_attrs
->dir
,
1630 ¬es_attrs
->attrs
[i
]))
1633 mod
->notes_attrs
= notes_attrs
;
1637 free_notes_attrs(notes_attrs
, i
);
1640 static void remove_notes_attrs(struct module
*mod
)
1642 if (mod
->notes_attrs
)
1643 free_notes_attrs(mod
->notes_attrs
, mod
->notes_attrs
->notes
);
1648 static inline void add_sect_attrs(struct module
*mod
,
1649 const struct load_info
*info
)
1653 static inline void remove_sect_attrs(struct module
*mod
)
1657 static inline void add_notes_attrs(struct module
*mod
,
1658 const struct load_info
*info
)
1662 static inline void remove_notes_attrs(struct module
*mod
)
1665 #endif /* CONFIG_KALLSYMS */
1667 static void del_usage_links(struct module
*mod
)
1669 #ifdef CONFIG_MODULE_UNLOAD
1670 struct module_use
*use
;
1672 mutex_lock(&module_mutex
);
1673 list_for_each_entry(use
, &mod
->target_list
, target_list
)
1674 sysfs_remove_link(use
->target
->holders_dir
, mod
->name
);
1675 mutex_unlock(&module_mutex
);
1679 static int add_usage_links(struct module
*mod
)
1682 #ifdef CONFIG_MODULE_UNLOAD
1683 struct module_use
*use
;
1685 mutex_lock(&module_mutex
);
1686 list_for_each_entry(use
, &mod
->target_list
, target_list
) {
1687 ret
= sysfs_create_link(use
->target
->holders_dir
,
1688 &mod
->mkobj
.kobj
, mod
->name
);
1692 mutex_unlock(&module_mutex
);
1694 del_usage_links(mod
);
1699 static void module_remove_modinfo_attrs(struct module
*mod
, int end
);
1701 static int module_add_modinfo_attrs(struct module
*mod
)
1703 struct module_attribute
*attr
;
1704 struct module_attribute
*temp_attr
;
1708 mod
->modinfo_attrs
= kzalloc((sizeof(struct module_attribute
) *
1709 (ARRAY_SIZE(modinfo_attrs
) + 1)),
1711 if (!mod
->modinfo_attrs
)
1714 temp_attr
= mod
->modinfo_attrs
;
1715 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
1716 if (!attr
->test
|| attr
->test(mod
)) {
1717 memcpy(temp_attr
, attr
, sizeof(*temp_attr
));
1718 sysfs_attr_init(&temp_attr
->attr
);
1719 error
= sysfs_create_file(&mod
->mkobj
.kobj
,
1731 module_remove_modinfo_attrs(mod
, --i
);
1735 static void module_remove_modinfo_attrs(struct module
*mod
, int end
)
1737 struct module_attribute
*attr
;
1740 for (i
= 0; (attr
= &mod
->modinfo_attrs
[i
]); i
++) {
1741 if (end
>= 0 && i
> end
)
1743 /* pick a field to test for end of list */
1744 if (!attr
->attr
.name
)
1746 sysfs_remove_file(&mod
->mkobj
.kobj
, &attr
->attr
);
1750 kfree(mod
->modinfo_attrs
);
1753 static void mod_kobject_put(struct module
*mod
)
1755 DECLARE_COMPLETION_ONSTACK(c
);
1756 mod
->mkobj
.kobj_completion
= &c
;
1757 kobject_put(&mod
->mkobj
.kobj
);
1758 wait_for_completion(&c
);
1761 static int mod_sysfs_init(struct module
*mod
)
1764 struct kobject
*kobj
;
1766 if (!module_sysfs_initialized
) {
1767 pr_err("%s: module sysfs not initialized\n", mod
->name
);
1772 kobj
= kset_find_obj(module_kset
, mod
->name
);
1774 pr_err("%s: module is already loaded\n", mod
->name
);
1780 mod
->mkobj
.mod
= mod
;
1782 memset(&mod
->mkobj
.kobj
, 0, sizeof(mod
->mkobj
.kobj
));
1783 mod
->mkobj
.kobj
.kset
= module_kset
;
1784 err
= kobject_init_and_add(&mod
->mkobj
.kobj
, &module_ktype
, NULL
,
1787 mod_kobject_put(mod
);
1789 /* delay uevent until full sysfs population */
1794 static int mod_sysfs_setup(struct module
*mod
,
1795 const struct load_info
*info
,
1796 struct kernel_param
*kparam
,
1797 unsigned int num_params
)
1801 err
= mod_sysfs_init(mod
);
1805 mod
->holders_dir
= kobject_create_and_add("holders", &mod
->mkobj
.kobj
);
1806 if (!mod
->holders_dir
) {
1811 err
= module_param_sysfs_setup(mod
, kparam
, num_params
);
1813 goto out_unreg_holders
;
1815 err
= module_add_modinfo_attrs(mod
);
1817 goto out_unreg_param
;
1819 err
= add_usage_links(mod
);
1821 goto out_unreg_modinfo_attrs
;
1823 add_sect_attrs(mod
, info
);
1824 add_notes_attrs(mod
, info
);
1826 kobject_uevent(&mod
->mkobj
.kobj
, KOBJ_ADD
);
1829 out_unreg_modinfo_attrs
:
1830 module_remove_modinfo_attrs(mod
, -1);
1832 module_param_sysfs_remove(mod
);
1834 kobject_put(mod
->holders_dir
);
1836 mod_kobject_put(mod
);
1841 static void mod_sysfs_fini(struct module
*mod
)
1843 remove_notes_attrs(mod
);
1844 remove_sect_attrs(mod
);
1845 mod_kobject_put(mod
);
1848 static void init_param_lock(struct module
*mod
)
1850 mutex_init(&mod
->param_lock
);
1852 #else /* !CONFIG_SYSFS */
1854 static int mod_sysfs_setup(struct module
*mod
,
1855 const struct load_info
*info
,
1856 struct kernel_param
*kparam
,
1857 unsigned int num_params
)
1862 static void mod_sysfs_fini(struct module
*mod
)
1866 static void module_remove_modinfo_attrs(struct module
*mod
, int end
)
1870 static void del_usage_links(struct module
*mod
)
1874 static void init_param_lock(struct module
*mod
)
1877 #endif /* CONFIG_SYSFS */
1879 static void mod_sysfs_teardown(struct module
*mod
)
1881 del_usage_links(mod
);
1882 module_remove_modinfo_attrs(mod
, -1);
1883 module_param_sysfs_remove(mod
);
1884 kobject_put(mod
->mkobj
.drivers_dir
);
1885 kobject_put(mod
->holders_dir
);
1886 mod_sysfs_fini(mod
);
1889 #ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX
1891 * LKM RO/NX protection: protect module's text/ro-data
1892 * from modification and any data from execution.
1894 * General layout of module is:
1895 * [text] [read-only-data] [ro-after-init] [writable data]
1896 * text_size -----^ ^ ^ ^
1897 * ro_size ------------------------| | |
1898 * ro_after_init_size -----------------------------| |
1899 * size -----------------------------------------------------------|
1901 * These values are always page-aligned (as is base)
1903 static void frob_text(const struct module_layout
*layout
,
1904 int (*set_memory
)(unsigned long start
, int num_pages
))
1906 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1907 BUG_ON((unsigned long)layout
->text_size
& (PAGE_SIZE
-1));
1908 set_memory((unsigned long)layout
->base
,
1909 layout
->text_size
>> PAGE_SHIFT
);
1912 #ifdef CONFIG_STRICT_MODULE_RWX
1913 static void frob_rodata(const struct module_layout
*layout
,
1914 int (*set_memory
)(unsigned long start
, int num_pages
))
1916 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1917 BUG_ON((unsigned long)layout
->text_size
& (PAGE_SIZE
-1));
1918 BUG_ON((unsigned long)layout
->ro_size
& (PAGE_SIZE
-1));
1919 set_memory((unsigned long)layout
->base
+ layout
->text_size
,
1920 (layout
->ro_size
- layout
->text_size
) >> PAGE_SHIFT
);
1923 static void frob_ro_after_init(const struct module_layout
*layout
,
1924 int (*set_memory
)(unsigned long start
, int num_pages
))
1926 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1927 BUG_ON((unsigned long)layout
->ro_size
& (PAGE_SIZE
-1));
1928 BUG_ON((unsigned long)layout
->ro_after_init_size
& (PAGE_SIZE
-1));
1929 set_memory((unsigned long)layout
->base
+ layout
->ro_size
,
1930 (layout
->ro_after_init_size
- layout
->ro_size
) >> PAGE_SHIFT
);
1933 static void frob_writable_data(const struct module_layout
*layout
,
1934 int (*set_memory
)(unsigned long start
, int num_pages
))
1936 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1937 BUG_ON((unsigned long)layout
->ro_after_init_size
& (PAGE_SIZE
-1));
1938 BUG_ON((unsigned long)layout
->size
& (PAGE_SIZE
-1));
1939 set_memory((unsigned long)layout
->base
+ layout
->ro_after_init_size
,
1940 (layout
->size
- layout
->ro_after_init_size
) >> PAGE_SHIFT
);
1943 /* livepatching wants to disable read-only so it can frob module. */
1944 void module_disable_ro(const struct module
*mod
)
1946 if (!rodata_enabled
)
1949 frob_text(&mod
->core_layout
, set_memory_rw
);
1950 frob_rodata(&mod
->core_layout
, set_memory_rw
);
1951 frob_ro_after_init(&mod
->core_layout
, set_memory_rw
);
1952 frob_text(&mod
->init_layout
, set_memory_rw
);
1953 frob_rodata(&mod
->init_layout
, set_memory_rw
);
1956 void module_enable_ro(const struct module
*mod
, bool after_init
)
1958 if (!rodata_enabled
)
1961 set_vm_flush_reset_perms(mod
->core_layout
.base
);
1962 set_vm_flush_reset_perms(mod
->init_layout
.base
);
1963 frob_text(&mod
->core_layout
, set_memory_ro
);
1965 frob_rodata(&mod
->core_layout
, set_memory_ro
);
1966 frob_text(&mod
->init_layout
, set_memory_ro
);
1967 frob_rodata(&mod
->init_layout
, set_memory_ro
);
1970 frob_ro_after_init(&mod
->core_layout
, set_memory_ro
);
1973 static void module_enable_nx(const struct module
*mod
)
1975 frob_rodata(&mod
->core_layout
, set_memory_nx
);
1976 frob_ro_after_init(&mod
->core_layout
, set_memory_nx
);
1977 frob_writable_data(&mod
->core_layout
, set_memory_nx
);
1978 frob_rodata(&mod
->init_layout
, set_memory_nx
);
1979 frob_writable_data(&mod
->init_layout
, set_memory_nx
);
1982 /* Iterate through all modules and set each module's text as RW */
1983 void set_all_modules_text_rw(void)
1987 if (!rodata_enabled
)
1990 mutex_lock(&module_mutex
);
1991 list_for_each_entry_rcu(mod
, &modules
, list
) {
1992 if (mod
->state
== MODULE_STATE_UNFORMED
)
1995 frob_text(&mod
->core_layout
, set_memory_rw
);
1996 frob_text(&mod
->init_layout
, set_memory_rw
);
1998 mutex_unlock(&module_mutex
);
2001 /* Iterate through all modules and set each module's text as RO */
2002 void set_all_modules_text_ro(void)
2006 if (!rodata_enabled
)
2009 mutex_lock(&module_mutex
);
2010 list_for_each_entry_rcu(mod
, &modules
, list
) {
2012 * Ignore going modules since it's possible that ro
2013 * protection has already been disabled, otherwise we'll
2014 * run into protection faults at module deallocation.
2016 if (mod
->state
== MODULE_STATE_UNFORMED
||
2017 mod
->state
== MODULE_STATE_GOING
)
2020 frob_text(&mod
->core_layout
, set_memory_ro
);
2021 frob_text(&mod
->init_layout
, set_memory_ro
);
2023 mutex_unlock(&module_mutex
);
2025 #else /* !CONFIG_STRICT_MODULE_RWX */
2026 static void module_enable_nx(const struct module
*mod
) { }
2027 #endif /* CONFIG_STRICT_MODULE_RWX */
2028 static void module_enable_x(const struct module
*mod
)
2030 frob_text(&mod
->core_layout
, set_memory_x
);
2031 frob_text(&mod
->init_layout
, set_memory_x
);
2033 #else /* !CONFIG_ARCH_HAS_STRICT_MODULE_RWX */
2034 static void module_enable_nx(const struct module
*mod
) { }
2035 static void module_enable_x(const struct module
*mod
) { }
2036 #endif /* CONFIG_ARCH_HAS_STRICT_MODULE_RWX */
2039 #ifdef CONFIG_LIVEPATCH
2041 * Persist Elf information about a module. Copy the Elf header,
2042 * section header table, section string table, and symtab section
2043 * index from info to mod->klp_info.
2045 static int copy_module_elf(struct module
*mod
, struct load_info
*info
)
2047 unsigned int size
, symndx
;
2050 size
= sizeof(*mod
->klp_info
);
2051 mod
->klp_info
= kmalloc(size
, GFP_KERNEL
);
2052 if (mod
->klp_info
== NULL
)
2056 size
= sizeof(mod
->klp_info
->hdr
);
2057 memcpy(&mod
->klp_info
->hdr
, info
->hdr
, size
);
2059 /* Elf section header table */
2060 size
= sizeof(*info
->sechdrs
) * info
->hdr
->e_shnum
;
2061 mod
->klp_info
->sechdrs
= kmemdup(info
->sechdrs
, size
, GFP_KERNEL
);
2062 if (mod
->klp_info
->sechdrs
== NULL
) {
2067 /* Elf section name string table */
2068 size
= info
->sechdrs
[info
->hdr
->e_shstrndx
].sh_size
;
2069 mod
->klp_info
->secstrings
= kmemdup(info
->secstrings
, size
, GFP_KERNEL
);
2070 if (mod
->klp_info
->secstrings
== NULL
) {
2075 /* Elf symbol section index */
2076 symndx
= info
->index
.sym
;
2077 mod
->klp_info
->symndx
= symndx
;
2080 * For livepatch modules, core_kallsyms.symtab is a complete
2081 * copy of the original symbol table. Adjust sh_addr to point
2082 * to core_kallsyms.symtab since the copy of the symtab in module
2083 * init memory is freed at the end of do_init_module().
2085 mod
->klp_info
->sechdrs
[symndx
].sh_addr
= \
2086 (unsigned long) mod
->core_kallsyms
.symtab
;
2091 kfree(mod
->klp_info
->sechdrs
);
2093 kfree(mod
->klp_info
);
2097 static void free_module_elf(struct module
*mod
)
2099 kfree(mod
->klp_info
->sechdrs
);
2100 kfree(mod
->klp_info
->secstrings
);
2101 kfree(mod
->klp_info
);
2103 #else /* !CONFIG_LIVEPATCH */
2104 static int copy_module_elf(struct module
*mod
, struct load_info
*info
)
2109 static void free_module_elf(struct module
*mod
)
2112 #endif /* CONFIG_LIVEPATCH */
2114 void __weak
module_memfree(void *module_region
)
2117 * This memory may be RO, and freeing RO memory in an interrupt is not
2118 * supported by vmalloc.
2120 WARN_ON(in_interrupt());
2121 vfree(module_region
);
2124 void __weak
module_arch_cleanup(struct module
*mod
)
2128 void __weak
module_arch_freeing_init(struct module
*mod
)
2132 /* Free a module, remove from lists, etc. */
2133 static void free_module(struct module
*mod
)
2135 trace_module_free(mod
);
2137 mod_sysfs_teardown(mod
);
2139 /* We leave it in list to prevent duplicate loads, but make sure
2140 * that noone uses it while it's being deconstructed. */
2141 mutex_lock(&module_mutex
);
2142 mod
->state
= MODULE_STATE_UNFORMED
;
2143 mutex_unlock(&module_mutex
);
2145 /* Remove dynamic debug info */
2146 ddebug_remove_module(mod
->name
);
2148 /* Arch-specific cleanup. */
2149 module_arch_cleanup(mod
);
2151 /* Module unload stuff */
2152 module_unload_free(mod
);
2154 /* Free any allocated parameters. */
2155 destroy_params(mod
->kp
, mod
->num_kp
);
2157 if (is_livepatch_module(mod
))
2158 free_module_elf(mod
);
2160 /* Now we can delete it from the lists */
2161 mutex_lock(&module_mutex
);
2162 /* Unlink carefully: kallsyms could be walking list. */
2163 list_del_rcu(&mod
->list
);
2164 mod_tree_remove(mod
);
2165 /* Remove this module from bug list, this uses list_del_rcu */
2166 module_bug_cleanup(mod
);
2167 /* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */
2169 mutex_unlock(&module_mutex
);
2171 /* This may be empty, but that's OK */
2172 module_arch_freeing_init(mod
);
2173 module_memfree(mod
->init_layout
.base
);
2175 percpu_modfree(mod
);
2177 /* Free lock-classes; relies on the preceding sync_rcu(). */
2178 lockdep_free_key_range(mod
->core_layout
.base
, mod
->core_layout
.size
);
2180 /* Finally, free the core (containing the module structure) */
2181 module_memfree(mod
->core_layout
.base
);
2184 void *__symbol_get(const char *symbol
)
2186 struct module
*owner
;
2187 const struct kernel_symbol
*sym
;
2190 sym
= find_symbol(symbol
, &owner
, NULL
, true, true);
2191 if (sym
&& strong_try_module_get(owner
))
2195 return sym
? (void *)kernel_symbol_value(sym
) : NULL
;
2197 EXPORT_SYMBOL_GPL(__symbol_get
);
2200 * Ensure that an exported symbol [global namespace] does not already exist
2201 * in the kernel or in some other module's exported symbol table.
2203 * You must hold the module_mutex.
2205 static int verify_exported_symbols(struct module
*mod
)
2208 struct module
*owner
;
2209 const struct kernel_symbol
*s
;
2211 const struct kernel_symbol
*sym
;
2214 { mod
->syms
, mod
->num_syms
},
2215 { mod
->gpl_syms
, mod
->num_gpl_syms
},
2216 { mod
->gpl_future_syms
, mod
->num_gpl_future_syms
},
2217 #ifdef CONFIG_UNUSED_SYMBOLS
2218 { mod
->unused_syms
, mod
->num_unused_syms
},
2219 { mod
->unused_gpl_syms
, mod
->num_unused_gpl_syms
},
2223 for (i
= 0; i
< ARRAY_SIZE(arr
); i
++) {
2224 for (s
= arr
[i
].sym
; s
< arr
[i
].sym
+ arr
[i
].num
; s
++) {
2225 if (find_symbol(kernel_symbol_name(s
), &owner
, NULL
,
2227 pr_err("%s: exports duplicate symbol %s"
2229 mod
->name
, kernel_symbol_name(s
),
2230 module_name(owner
));
2238 /* Change all symbols so that st_value encodes the pointer directly. */
2239 static int simplify_symbols(struct module
*mod
, const struct load_info
*info
)
2241 Elf_Shdr
*symsec
= &info
->sechdrs
[info
->index
.sym
];
2242 Elf_Sym
*sym
= (void *)symsec
->sh_addr
;
2243 unsigned long secbase
;
2246 const struct kernel_symbol
*ksym
;
2248 for (i
= 1; i
< symsec
->sh_size
/ sizeof(Elf_Sym
); i
++) {
2249 const char *name
= info
->strtab
+ sym
[i
].st_name
;
2251 switch (sym
[i
].st_shndx
) {
2253 /* Ignore common symbols */
2254 if (!strncmp(name
, "__gnu_lto", 9))
2257 /* We compiled with -fno-common. These are not
2258 supposed to happen. */
2259 pr_debug("Common symbol: %s\n", name
);
2260 pr_warn("%s: please compile with -fno-common\n",
2266 /* Don't need to do anything */
2267 pr_debug("Absolute symbol: 0x%08lx\n",
2268 (long)sym
[i
].st_value
);
2272 /* Livepatch symbols are resolved by livepatch */
2276 ksym
= resolve_symbol_wait(mod
, info
, name
);
2277 /* Ok if resolved. */
2278 if (ksym
&& !IS_ERR(ksym
)) {
2279 sym
[i
].st_value
= kernel_symbol_value(ksym
);
2284 if (!ksym
&& ELF_ST_BIND(sym
[i
].st_info
) == STB_WEAK
)
2287 ret
= PTR_ERR(ksym
) ?: -ENOENT
;
2288 pr_warn("%s: Unknown symbol %s (err %d)\n",
2289 mod
->name
, name
, ret
);
2293 /* Divert to percpu allocation if a percpu var. */
2294 if (sym
[i
].st_shndx
== info
->index
.pcpu
)
2295 secbase
= (unsigned long)mod_percpu(mod
);
2297 secbase
= info
->sechdrs
[sym
[i
].st_shndx
].sh_addr
;
2298 sym
[i
].st_value
+= secbase
;
2306 static int apply_relocations(struct module
*mod
, const struct load_info
*info
)
2311 /* Now do relocations. */
2312 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2313 unsigned int infosec
= info
->sechdrs
[i
].sh_info
;
2315 /* Not a valid relocation section? */
2316 if (infosec
>= info
->hdr
->e_shnum
)
2319 /* Don't bother with non-allocated sections */
2320 if (!(info
->sechdrs
[infosec
].sh_flags
& SHF_ALLOC
))
2323 /* Livepatch relocation sections are applied by livepatch */
2324 if (info
->sechdrs
[i
].sh_flags
& SHF_RELA_LIVEPATCH
)
2327 if (info
->sechdrs
[i
].sh_type
== SHT_REL
)
2328 err
= apply_relocate(info
->sechdrs
, info
->strtab
,
2329 info
->index
.sym
, i
, mod
);
2330 else if (info
->sechdrs
[i
].sh_type
== SHT_RELA
)
2331 err
= apply_relocate_add(info
->sechdrs
, info
->strtab
,
2332 info
->index
.sym
, i
, mod
);
2339 /* Additional bytes needed by arch in front of individual sections */
2340 unsigned int __weak
arch_mod_section_prepend(struct module
*mod
,
2341 unsigned int section
)
2343 /* default implementation just returns zero */
2347 /* Update size with this section: return offset. */
2348 static long get_offset(struct module
*mod
, unsigned int *size
,
2349 Elf_Shdr
*sechdr
, unsigned int section
)
2353 *size
+= arch_mod_section_prepend(mod
, section
);
2354 ret
= ALIGN(*size
, sechdr
->sh_addralign
?: 1);
2355 *size
= ret
+ sechdr
->sh_size
;
2359 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
2360 might -- code, read-only data, read-write data, small data. Tally
2361 sizes, and place the offsets into sh_entsize fields: high bit means it
2363 static void layout_sections(struct module
*mod
, struct load_info
*info
)
2365 static unsigned long const masks
[][2] = {
2366 /* NOTE: all executable code must be the first section
2367 * in this array; otherwise modify the text_size
2368 * finder in the two loops below */
2369 { SHF_EXECINSTR
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2370 { SHF_ALLOC
, SHF_WRITE
| ARCH_SHF_SMALL
},
2371 { SHF_RO_AFTER_INIT
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2372 { SHF_WRITE
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2373 { ARCH_SHF_SMALL
| SHF_ALLOC
, 0 }
2377 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
2378 info
->sechdrs
[i
].sh_entsize
= ~0UL;
2380 pr_debug("Core section allocation order:\n");
2381 for (m
= 0; m
< ARRAY_SIZE(masks
); ++m
) {
2382 for (i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
2383 Elf_Shdr
*s
= &info
->sechdrs
[i
];
2384 const char *sname
= info
->secstrings
+ s
->sh_name
;
2386 if ((s
->sh_flags
& masks
[m
][0]) != masks
[m
][0]
2387 || (s
->sh_flags
& masks
[m
][1])
2388 || s
->sh_entsize
!= ~0UL
2389 || strstarts(sname
, ".init"))
2391 s
->sh_entsize
= get_offset(mod
, &mod
->core_layout
.size
, s
, i
);
2392 pr_debug("\t%s\n", sname
);
2395 case 0: /* executable */
2396 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2397 mod
->core_layout
.text_size
= mod
->core_layout
.size
;
2399 case 1: /* RO: text and ro-data */
2400 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2401 mod
->core_layout
.ro_size
= mod
->core_layout
.size
;
2403 case 2: /* RO after init */
2404 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2405 mod
->core_layout
.ro_after_init_size
= mod
->core_layout
.size
;
2407 case 4: /* whole core */
2408 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2413 pr_debug("Init section allocation order:\n");
2414 for (m
= 0; m
< ARRAY_SIZE(masks
); ++m
) {
2415 for (i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
2416 Elf_Shdr
*s
= &info
->sechdrs
[i
];
2417 const char *sname
= info
->secstrings
+ s
->sh_name
;
2419 if ((s
->sh_flags
& masks
[m
][0]) != masks
[m
][0]
2420 || (s
->sh_flags
& masks
[m
][1])
2421 || s
->sh_entsize
!= ~0UL
2422 || !strstarts(sname
, ".init"))
2424 s
->sh_entsize
= (get_offset(mod
, &mod
->init_layout
.size
, s
, i
)
2425 | INIT_OFFSET_MASK
);
2426 pr_debug("\t%s\n", sname
);
2429 case 0: /* executable */
2430 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2431 mod
->init_layout
.text_size
= mod
->init_layout
.size
;
2433 case 1: /* RO: text and ro-data */
2434 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2435 mod
->init_layout
.ro_size
= mod
->init_layout
.size
;
2439 * RO after init doesn't apply to init_layout (only
2440 * core_layout), so it just takes the value of ro_size.
2442 mod
->init_layout
.ro_after_init_size
= mod
->init_layout
.ro_size
;
2444 case 4: /* whole init */
2445 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2451 static void set_license(struct module
*mod
, const char *license
)
2454 license
= "unspecified";
2456 if (!license_is_gpl_compatible(license
)) {
2457 if (!test_taint(TAINT_PROPRIETARY_MODULE
))
2458 pr_warn("%s: module license '%s' taints kernel.\n",
2459 mod
->name
, license
);
2460 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
2461 LOCKDEP_NOW_UNRELIABLE
);
2465 /* Parse tag=value strings from .modinfo section */
2466 static char *next_string(char *string
, unsigned long *secsize
)
2468 /* Skip non-zero chars */
2471 if ((*secsize
)-- <= 1)
2475 /* Skip any zero padding. */
2476 while (!string
[0]) {
2478 if ((*secsize
)-- <= 1)
2484 static char *get_modinfo(struct load_info
*info
, const char *tag
)
2487 unsigned int taglen
= strlen(tag
);
2488 Elf_Shdr
*infosec
= &info
->sechdrs
[info
->index
.info
];
2489 unsigned long size
= infosec
->sh_size
;
2492 * get_modinfo() calls made before rewrite_section_headers()
2493 * must use sh_offset, as sh_addr isn't set!
2495 for (p
= (char *)info
->hdr
+ infosec
->sh_offset
; p
; p
= next_string(p
, &size
)) {
2496 if (strncmp(p
, tag
, taglen
) == 0 && p
[taglen
] == '=')
2497 return p
+ taglen
+ 1;
2502 static void setup_modinfo(struct module
*mod
, struct load_info
*info
)
2504 struct module_attribute
*attr
;
2507 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
2509 attr
->setup(mod
, get_modinfo(info
, attr
->attr
.name
));
2513 static void free_modinfo(struct module
*mod
)
2515 struct module_attribute
*attr
;
2518 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
2524 #ifdef CONFIG_KALLSYMS
2526 /* Lookup exported symbol in given range of kernel_symbols */
2527 static const struct kernel_symbol
*lookup_exported_symbol(const char *name
,
2528 const struct kernel_symbol
*start
,
2529 const struct kernel_symbol
*stop
)
2531 return bsearch(name
, start
, stop
- start
,
2532 sizeof(struct kernel_symbol
), cmp_name
);
2535 static int is_exported(const char *name
, unsigned long value
,
2536 const struct module
*mod
)
2538 const struct kernel_symbol
*ks
;
2540 ks
= lookup_exported_symbol(name
, __start___ksymtab
, __stop___ksymtab
);
2542 ks
= lookup_exported_symbol(name
, mod
->syms
, mod
->syms
+ mod
->num_syms
);
2544 return ks
!= NULL
&& kernel_symbol_value(ks
) == value
;
2548 static char elf_type(const Elf_Sym
*sym
, const struct load_info
*info
)
2550 const Elf_Shdr
*sechdrs
= info
->sechdrs
;
2552 if (ELF_ST_BIND(sym
->st_info
) == STB_WEAK
) {
2553 if (ELF_ST_TYPE(sym
->st_info
) == STT_OBJECT
)
2558 if (sym
->st_shndx
== SHN_UNDEF
)
2560 if (sym
->st_shndx
== SHN_ABS
|| sym
->st_shndx
== info
->index
.pcpu
)
2562 if (sym
->st_shndx
>= SHN_LORESERVE
)
2564 if (sechdrs
[sym
->st_shndx
].sh_flags
& SHF_EXECINSTR
)
2566 if (sechdrs
[sym
->st_shndx
].sh_flags
& SHF_ALLOC
2567 && sechdrs
[sym
->st_shndx
].sh_type
!= SHT_NOBITS
) {
2568 if (!(sechdrs
[sym
->st_shndx
].sh_flags
& SHF_WRITE
))
2570 else if (sechdrs
[sym
->st_shndx
].sh_flags
& ARCH_SHF_SMALL
)
2575 if (sechdrs
[sym
->st_shndx
].sh_type
== SHT_NOBITS
) {
2576 if (sechdrs
[sym
->st_shndx
].sh_flags
& ARCH_SHF_SMALL
)
2581 if (strstarts(info
->secstrings
+ sechdrs
[sym
->st_shndx
].sh_name
,
2588 static bool is_core_symbol(const Elf_Sym
*src
, const Elf_Shdr
*sechdrs
,
2589 unsigned int shnum
, unsigned int pcpundx
)
2591 const Elf_Shdr
*sec
;
2593 if (src
->st_shndx
== SHN_UNDEF
2594 || src
->st_shndx
>= shnum
2598 #ifdef CONFIG_KALLSYMS_ALL
2599 if (src
->st_shndx
== pcpundx
)
2603 sec
= sechdrs
+ src
->st_shndx
;
2604 if (!(sec
->sh_flags
& SHF_ALLOC
)
2605 #ifndef CONFIG_KALLSYMS_ALL
2606 || !(sec
->sh_flags
& SHF_EXECINSTR
)
2608 || (sec
->sh_entsize
& INIT_OFFSET_MASK
))
2615 * We only allocate and copy the strings needed by the parts of symtab
2616 * we keep. This is simple, but has the effect of making multiple
2617 * copies of duplicates. We could be more sophisticated, see
2618 * linux-kernel thread starting with
2619 * <73defb5e4bca04a6431392cc341112b1@localhost>.
2621 static void layout_symtab(struct module
*mod
, struct load_info
*info
)
2623 Elf_Shdr
*symsect
= info
->sechdrs
+ info
->index
.sym
;
2624 Elf_Shdr
*strsect
= info
->sechdrs
+ info
->index
.str
;
2626 unsigned int i
, nsrc
, ndst
, strtab_size
= 0;
2628 /* Put symbol section at end of init part of module. */
2629 symsect
->sh_flags
|= SHF_ALLOC
;
2630 symsect
->sh_entsize
= get_offset(mod
, &mod
->init_layout
.size
, symsect
,
2631 info
->index
.sym
) | INIT_OFFSET_MASK
;
2632 pr_debug("\t%s\n", info
->secstrings
+ symsect
->sh_name
);
2634 src
= (void *)info
->hdr
+ symsect
->sh_offset
;
2635 nsrc
= symsect
->sh_size
/ sizeof(*src
);
2637 /* Compute total space required for the core symbols' strtab. */
2638 for (ndst
= i
= 0; i
< nsrc
; i
++) {
2639 if (i
== 0 || is_livepatch_module(mod
) ||
2640 is_core_symbol(src
+i
, info
->sechdrs
, info
->hdr
->e_shnum
,
2641 info
->index
.pcpu
)) {
2642 strtab_size
+= strlen(&info
->strtab
[src
[i
].st_name
])+1;
2647 /* Append room for core symbols at end of core part. */
2648 info
->symoffs
= ALIGN(mod
->core_layout
.size
, symsect
->sh_addralign
?: 1);
2649 info
->stroffs
= mod
->core_layout
.size
= info
->symoffs
+ ndst
* sizeof(Elf_Sym
);
2650 mod
->core_layout
.size
+= strtab_size
;
2651 info
->core_typeoffs
= mod
->core_layout
.size
;
2652 mod
->core_layout
.size
+= ndst
* sizeof(char);
2653 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2655 /* Put string table section at end of init part of module. */
2656 strsect
->sh_flags
|= SHF_ALLOC
;
2657 strsect
->sh_entsize
= get_offset(mod
, &mod
->init_layout
.size
, strsect
,
2658 info
->index
.str
) | INIT_OFFSET_MASK
;
2659 pr_debug("\t%s\n", info
->secstrings
+ strsect
->sh_name
);
2661 /* We'll tack temporary mod_kallsyms on the end. */
2662 mod
->init_layout
.size
= ALIGN(mod
->init_layout
.size
,
2663 __alignof__(struct mod_kallsyms
));
2664 info
->mod_kallsyms_init_off
= mod
->init_layout
.size
;
2665 mod
->init_layout
.size
+= sizeof(struct mod_kallsyms
);
2666 info
->init_typeoffs
= mod
->init_layout
.size
;
2667 mod
->init_layout
.size
+= nsrc
* sizeof(char);
2668 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2672 * We use the full symtab and strtab which layout_symtab arranged to
2673 * be appended to the init section. Later we switch to the cut-down
2676 static void add_kallsyms(struct module
*mod
, const struct load_info
*info
)
2678 unsigned int i
, ndst
;
2682 Elf_Shdr
*symsec
= &info
->sechdrs
[info
->index
.sym
];
2684 /* Set up to point into init section. */
2685 mod
->kallsyms
= mod
->init_layout
.base
+ info
->mod_kallsyms_init_off
;
2687 mod
->kallsyms
->symtab
= (void *)symsec
->sh_addr
;
2688 mod
->kallsyms
->num_symtab
= symsec
->sh_size
/ sizeof(Elf_Sym
);
2689 /* Make sure we get permanent strtab: don't use info->strtab. */
2690 mod
->kallsyms
->strtab
= (void *)info
->sechdrs
[info
->index
.str
].sh_addr
;
2691 mod
->kallsyms
->typetab
= mod
->init_layout
.base
+ info
->init_typeoffs
;
2694 * Now populate the cut down core kallsyms for after init
2695 * and set types up while we still have access to sections.
2697 mod
->core_kallsyms
.symtab
= dst
= mod
->core_layout
.base
+ info
->symoffs
;
2698 mod
->core_kallsyms
.strtab
= s
= mod
->core_layout
.base
+ info
->stroffs
;
2699 mod
->core_kallsyms
.typetab
= mod
->core_layout
.base
+ info
->core_typeoffs
;
2700 src
= mod
->kallsyms
->symtab
;
2701 for (ndst
= i
= 0; i
< mod
->kallsyms
->num_symtab
; i
++) {
2702 mod
->kallsyms
->typetab
[i
] = elf_type(src
+ i
, info
);
2703 if (i
== 0 || is_livepatch_module(mod
) ||
2704 is_core_symbol(src
+i
, info
->sechdrs
, info
->hdr
->e_shnum
,
2705 info
->index
.pcpu
)) {
2706 mod
->core_kallsyms
.typetab
[ndst
] =
2707 mod
->kallsyms
->typetab
[i
];
2709 dst
[ndst
++].st_name
= s
- mod
->core_kallsyms
.strtab
;
2710 s
+= strlcpy(s
, &mod
->kallsyms
->strtab
[src
[i
].st_name
],
2714 mod
->core_kallsyms
.num_symtab
= ndst
;
2717 static inline void layout_symtab(struct module
*mod
, struct load_info
*info
)
2721 static void add_kallsyms(struct module
*mod
, const struct load_info
*info
)
2724 #endif /* CONFIG_KALLSYMS */
2726 static void dynamic_debug_setup(struct module
*mod
, struct _ddebug
*debug
, unsigned int num
)
2730 ddebug_add_module(debug
, num
, mod
->name
);
2733 static void dynamic_debug_remove(struct module
*mod
, struct _ddebug
*debug
)
2736 ddebug_remove_module(mod
->name
);
2739 void * __weak
module_alloc(unsigned long size
)
2741 return vmalloc_exec(size
);
2744 bool __weak
module_exit_section(const char *name
)
2746 return strstarts(name
, ".exit");
2749 #ifdef CONFIG_DEBUG_KMEMLEAK
2750 static void kmemleak_load_module(const struct module
*mod
,
2751 const struct load_info
*info
)
2755 /* only scan the sections containing data */
2756 kmemleak_scan_area(mod
, sizeof(struct module
), GFP_KERNEL
);
2758 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2759 /* Scan all writable sections that's not executable */
2760 if (!(info
->sechdrs
[i
].sh_flags
& SHF_ALLOC
) ||
2761 !(info
->sechdrs
[i
].sh_flags
& SHF_WRITE
) ||
2762 (info
->sechdrs
[i
].sh_flags
& SHF_EXECINSTR
))
2765 kmemleak_scan_area((void *)info
->sechdrs
[i
].sh_addr
,
2766 info
->sechdrs
[i
].sh_size
, GFP_KERNEL
);
2770 static inline void kmemleak_load_module(const struct module
*mod
,
2771 const struct load_info
*info
)
2776 #ifdef CONFIG_MODULE_SIG
2777 static int module_sig_check(struct load_info
*info
, int flags
)
2780 const unsigned long markerlen
= sizeof(MODULE_SIG_STRING
) - 1;
2781 const void *mod
= info
->hdr
;
2784 * Require flags == 0, as a module with version information
2785 * removed is no longer the module that was signed
2788 info
->len
> markerlen
&&
2789 memcmp(mod
+ info
->len
- markerlen
, MODULE_SIG_STRING
, markerlen
) == 0) {
2790 /* We truncate the module to discard the signature */
2791 info
->len
-= markerlen
;
2792 err
= mod_verify_sig(mod
, info
);
2796 info
->sig_ok
= true;
2800 /* Not having a signature is only an error if we're strict. */
2801 if (err
== -ENOKEY
&& !is_module_sig_enforced())
2806 #else /* !CONFIG_MODULE_SIG */
2807 static int module_sig_check(struct load_info
*info
, int flags
)
2811 #endif /* !CONFIG_MODULE_SIG */
2813 /* Sanity checks against invalid binaries, wrong arch, weird elf version. */
2814 static int elf_header_check(struct load_info
*info
)
2816 if (info
->len
< sizeof(*(info
->hdr
)))
2819 if (memcmp(info
->hdr
->e_ident
, ELFMAG
, SELFMAG
) != 0
2820 || info
->hdr
->e_type
!= ET_REL
2821 || !elf_check_arch(info
->hdr
)
2822 || info
->hdr
->e_shentsize
!= sizeof(Elf_Shdr
))
2825 if (info
->hdr
->e_shoff
>= info
->len
2826 || (info
->hdr
->e_shnum
* sizeof(Elf_Shdr
) >
2827 info
->len
- info
->hdr
->e_shoff
))
2833 #define COPY_CHUNK_SIZE (16*PAGE_SIZE)
2835 static int copy_chunked_from_user(void *dst
, const void __user
*usrc
, unsigned long len
)
2838 unsigned long n
= min(len
, COPY_CHUNK_SIZE
);
2840 if (copy_from_user(dst
, usrc
, n
) != 0)
2850 #ifdef CONFIG_LIVEPATCH
2851 static int check_modinfo_livepatch(struct module
*mod
, struct load_info
*info
)
2853 if (get_modinfo(info
, "livepatch")) {
2855 add_taint_module(mod
, TAINT_LIVEPATCH
, LOCKDEP_STILL_OK
);
2856 pr_notice_once("%s: tainting kernel with TAINT_LIVEPATCH\n",
2862 #else /* !CONFIG_LIVEPATCH */
2863 static int check_modinfo_livepatch(struct module
*mod
, struct load_info
*info
)
2865 if (get_modinfo(info
, "livepatch")) {
2866 pr_err("%s: module is marked as livepatch module, but livepatch support is disabled",
2873 #endif /* CONFIG_LIVEPATCH */
2875 static void check_modinfo_retpoline(struct module
*mod
, struct load_info
*info
)
2877 if (retpoline_module_ok(get_modinfo(info
, "retpoline")))
2880 pr_warn("%s: loading module not compiled with retpoline compiler.\n",
2884 /* Sets info->hdr and info->len. */
2885 static int copy_module_from_user(const void __user
*umod
, unsigned long len
,
2886 struct load_info
*info
)
2891 if (info
->len
< sizeof(*(info
->hdr
)))
2894 err
= security_kernel_load_data(LOADING_MODULE
);
2898 /* Suck in entire file: we'll want most of it. */
2899 info
->hdr
= __vmalloc(info
->len
,
2900 GFP_KERNEL
| __GFP_NOWARN
, PAGE_KERNEL
);
2904 if (copy_chunked_from_user(info
->hdr
, umod
, info
->len
) != 0) {
2912 static void free_copy(struct load_info
*info
)
2917 static int rewrite_section_headers(struct load_info
*info
, int flags
)
2921 /* This should always be true, but let's be sure. */
2922 info
->sechdrs
[0].sh_addr
= 0;
2924 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2925 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
2926 if (shdr
->sh_type
!= SHT_NOBITS
2927 && info
->len
< shdr
->sh_offset
+ shdr
->sh_size
) {
2928 pr_err("Module len %lu truncated\n", info
->len
);
2932 /* Mark all sections sh_addr with their address in the
2934 shdr
->sh_addr
= (size_t)info
->hdr
+ shdr
->sh_offset
;
2936 #ifndef CONFIG_MODULE_UNLOAD
2937 /* Don't load .exit sections */
2938 if (module_exit_section(info
->secstrings
+shdr
->sh_name
))
2939 shdr
->sh_flags
&= ~(unsigned long)SHF_ALLOC
;
2943 /* Track but don't keep modinfo and version sections. */
2944 info
->sechdrs
[info
->index
.vers
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
2945 info
->sechdrs
[info
->index
.info
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
2951 * Set up our basic convenience variables (pointers to section headers,
2952 * search for module section index etc), and do some basic section
2955 * Set info->mod to the temporary copy of the module in info->hdr. The final one
2956 * will be allocated in move_module().
2958 static int setup_load_info(struct load_info
*info
, int flags
)
2962 /* Set up the convenience variables */
2963 info
->sechdrs
= (void *)info
->hdr
+ info
->hdr
->e_shoff
;
2964 info
->secstrings
= (void *)info
->hdr
2965 + info
->sechdrs
[info
->hdr
->e_shstrndx
].sh_offset
;
2967 /* Try to find a name early so we can log errors with a module name */
2968 info
->index
.info
= find_sec(info
, ".modinfo");
2969 if (!info
->index
.info
)
2970 info
->name
= "(missing .modinfo section)";
2972 info
->name
= get_modinfo(info
, "name");
2974 /* Find internal symbols and strings. */
2975 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2976 if (info
->sechdrs
[i
].sh_type
== SHT_SYMTAB
) {
2977 info
->index
.sym
= i
;
2978 info
->index
.str
= info
->sechdrs
[i
].sh_link
;
2979 info
->strtab
= (char *)info
->hdr
2980 + info
->sechdrs
[info
->index
.str
].sh_offset
;
2985 if (info
->index
.sym
== 0) {
2986 pr_warn("%s: module has no symbols (stripped?)\n", info
->name
);
2990 info
->index
.mod
= find_sec(info
, ".gnu.linkonce.this_module");
2991 if (!info
->index
.mod
) {
2992 pr_warn("%s: No module found in object\n",
2993 info
->name
?: "(missing .modinfo name field)");
2996 /* This is temporary: point mod into copy of data. */
2997 info
->mod
= (void *)info
->hdr
+ info
->sechdrs
[info
->index
.mod
].sh_offset
;
3000 * If we didn't load the .modinfo 'name' field earlier, fall back to
3001 * on-disk struct mod 'name' field.
3004 info
->name
= info
->mod
->name
;
3006 if (flags
& MODULE_INIT_IGNORE_MODVERSIONS
)
3007 info
->index
.vers
= 0; /* Pretend no __versions section! */
3009 info
->index
.vers
= find_sec(info
, "__versions");
3011 info
->index
.pcpu
= find_pcpusec(info
);
3016 static int check_modinfo(struct module
*mod
, struct load_info
*info
, int flags
)
3018 const char *modmagic
= get_modinfo(info
, "vermagic");
3021 if (flags
& MODULE_INIT_IGNORE_VERMAGIC
)
3024 /* This is allowed: modprobe --force will invalidate it. */
3026 err
= try_to_force_load(mod
, "bad vermagic");
3029 } else if (!same_magic(modmagic
, vermagic
, info
->index
.vers
)) {
3030 pr_err("%s: version magic '%s' should be '%s'\n",
3031 info
->name
, modmagic
, vermagic
);
3035 if (!get_modinfo(info
, "intree")) {
3036 if (!test_taint(TAINT_OOT_MODULE
))
3037 pr_warn("%s: loading out-of-tree module taints kernel.\n",
3039 add_taint_module(mod
, TAINT_OOT_MODULE
, LOCKDEP_STILL_OK
);
3042 check_modinfo_retpoline(mod
, info
);
3044 if (get_modinfo(info
, "staging")) {
3045 add_taint_module(mod
, TAINT_CRAP
, LOCKDEP_STILL_OK
);
3046 pr_warn("%s: module is from the staging directory, the quality "
3047 "is unknown, you have been warned.\n", mod
->name
);
3050 err
= check_modinfo_livepatch(mod
, info
);
3054 /* Set up license info based on the info section */
3055 set_license(mod
, get_modinfo(info
, "license"));
3060 static int find_module_sections(struct module
*mod
, struct load_info
*info
)
3062 mod
->kp
= section_objs(info
, "__param",
3063 sizeof(*mod
->kp
), &mod
->num_kp
);
3064 mod
->syms
= section_objs(info
, "__ksymtab",
3065 sizeof(*mod
->syms
), &mod
->num_syms
);
3066 mod
->crcs
= section_addr(info
, "__kcrctab");
3067 mod
->gpl_syms
= section_objs(info
, "__ksymtab_gpl",
3068 sizeof(*mod
->gpl_syms
),
3069 &mod
->num_gpl_syms
);
3070 mod
->gpl_crcs
= section_addr(info
, "__kcrctab_gpl");
3071 mod
->gpl_future_syms
= section_objs(info
,
3072 "__ksymtab_gpl_future",
3073 sizeof(*mod
->gpl_future_syms
),
3074 &mod
->num_gpl_future_syms
);
3075 mod
->gpl_future_crcs
= section_addr(info
, "__kcrctab_gpl_future");
3077 #ifdef CONFIG_UNUSED_SYMBOLS
3078 mod
->unused_syms
= section_objs(info
, "__ksymtab_unused",
3079 sizeof(*mod
->unused_syms
),
3080 &mod
->num_unused_syms
);
3081 mod
->unused_crcs
= section_addr(info
, "__kcrctab_unused");
3082 mod
->unused_gpl_syms
= section_objs(info
, "__ksymtab_unused_gpl",
3083 sizeof(*mod
->unused_gpl_syms
),
3084 &mod
->num_unused_gpl_syms
);
3085 mod
->unused_gpl_crcs
= section_addr(info
, "__kcrctab_unused_gpl");
3087 #ifdef CONFIG_CONSTRUCTORS
3088 mod
->ctors
= section_objs(info
, ".ctors",
3089 sizeof(*mod
->ctors
), &mod
->num_ctors
);
3091 mod
->ctors
= section_objs(info
, ".init_array",
3092 sizeof(*mod
->ctors
), &mod
->num_ctors
);
3093 else if (find_sec(info
, ".init_array")) {
3095 * This shouldn't happen with same compiler and binutils
3096 * building all parts of the module.
3098 pr_warn("%s: has both .ctors and .init_array.\n",
3104 #ifdef CONFIG_TRACEPOINTS
3105 mod
->tracepoints_ptrs
= section_objs(info
, "__tracepoints_ptrs",
3106 sizeof(*mod
->tracepoints_ptrs
),
3107 &mod
->num_tracepoints
);
3109 #ifdef CONFIG_TREE_SRCU
3110 mod
->srcu_struct_ptrs
= section_objs(info
, "___srcu_struct_ptrs",
3111 sizeof(*mod
->srcu_struct_ptrs
),
3112 &mod
->num_srcu_structs
);
3114 #ifdef CONFIG_BPF_EVENTS
3115 mod
->bpf_raw_events
= section_objs(info
, "__bpf_raw_tp_map",
3116 sizeof(*mod
->bpf_raw_events
),
3117 &mod
->num_bpf_raw_events
);
3119 #ifdef CONFIG_JUMP_LABEL
3120 mod
->jump_entries
= section_objs(info
, "__jump_table",
3121 sizeof(*mod
->jump_entries
),
3122 &mod
->num_jump_entries
);
3124 #ifdef CONFIG_EVENT_TRACING
3125 mod
->trace_events
= section_objs(info
, "_ftrace_events",
3126 sizeof(*mod
->trace_events
),
3127 &mod
->num_trace_events
);
3128 mod
->trace_evals
= section_objs(info
, "_ftrace_eval_map",
3129 sizeof(*mod
->trace_evals
),
3130 &mod
->num_trace_evals
);
3132 #ifdef CONFIG_TRACING
3133 mod
->trace_bprintk_fmt_start
= section_objs(info
, "__trace_printk_fmt",
3134 sizeof(*mod
->trace_bprintk_fmt_start
),
3135 &mod
->num_trace_bprintk_fmt
);
3137 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
3138 /* sechdrs[0].sh_size is always zero */
3139 mod
->ftrace_callsites
= section_objs(info
, "__mcount_loc",
3140 sizeof(*mod
->ftrace_callsites
),
3141 &mod
->num_ftrace_callsites
);
3143 #ifdef CONFIG_FUNCTION_ERROR_INJECTION
3144 mod
->ei_funcs
= section_objs(info
, "_error_injection_whitelist",
3145 sizeof(*mod
->ei_funcs
),
3146 &mod
->num_ei_funcs
);
3148 mod
->extable
= section_objs(info
, "__ex_table",
3149 sizeof(*mod
->extable
), &mod
->num_exentries
);
3151 if (section_addr(info
, "__obsparm"))
3152 pr_warn("%s: Ignoring obsolete parameters\n", mod
->name
);
3154 info
->debug
= section_objs(info
, "__verbose",
3155 sizeof(*info
->debug
), &info
->num_debug
);
3160 static int move_module(struct module
*mod
, struct load_info
*info
)
3165 /* Do the allocs. */
3166 ptr
= module_alloc(mod
->core_layout
.size
);
3168 * The pointer to this block is stored in the module structure
3169 * which is inside the block. Just mark it as not being a
3172 kmemleak_not_leak(ptr
);
3176 memset(ptr
, 0, mod
->core_layout
.size
);
3177 mod
->core_layout
.base
= ptr
;
3179 if (mod
->init_layout
.size
) {
3180 ptr
= module_alloc(mod
->init_layout
.size
);
3182 * The pointer to this block is stored in the module structure
3183 * which is inside the block. This block doesn't need to be
3184 * scanned as it contains data and code that will be freed
3185 * after the module is initialized.
3187 kmemleak_ignore(ptr
);
3189 module_memfree(mod
->core_layout
.base
);
3192 memset(ptr
, 0, mod
->init_layout
.size
);
3193 mod
->init_layout
.base
= ptr
;
3195 mod
->init_layout
.base
= NULL
;
3197 /* Transfer each section which specifies SHF_ALLOC */
3198 pr_debug("final section addresses:\n");
3199 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++) {
3201 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
3203 if (!(shdr
->sh_flags
& SHF_ALLOC
))
3206 if (shdr
->sh_entsize
& INIT_OFFSET_MASK
)
3207 dest
= mod
->init_layout
.base
3208 + (shdr
->sh_entsize
& ~INIT_OFFSET_MASK
);
3210 dest
= mod
->core_layout
.base
+ shdr
->sh_entsize
;
3212 if (shdr
->sh_type
!= SHT_NOBITS
)
3213 memcpy(dest
, (void *)shdr
->sh_addr
, shdr
->sh_size
);
3214 /* Update sh_addr to point to copy in image. */
3215 shdr
->sh_addr
= (unsigned long)dest
;
3216 pr_debug("\t0x%lx %s\n",
3217 (long)shdr
->sh_addr
, info
->secstrings
+ shdr
->sh_name
);
3223 static int check_module_license_and_versions(struct module
*mod
)
3225 int prev_taint
= test_taint(TAINT_PROPRIETARY_MODULE
);
3228 * ndiswrapper is under GPL by itself, but loads proprietary modules.
3229 * Don't use add_taint_module(), as it would prevent ndiswrapper from
3230 * using GPL-only symbols it needs.
3232 if (strcmp(mod
->name
, "ndiswrapper") == 0)
3233 add_taint(TAINT_PROPRIETARY_MODULE
, LOCKDEP_NOW_UNRELIABLE
);
3235 /* driverloader was caught wrongly pretending to be under GPL */
3236 if (strcmp(mod
->name
, "driverloader") == 0)
3237 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
3238 LOCKDEP_NOW_UNRELIABLE
);
3240 /* lve claims to be GPL but upstream won't provide source */
3241 if (strcmp(mod
->name
, "lve") == 0)
3242 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
3243 LOCKDEP_NOW_UNRELIABLE
);
3245 if (!prev_taint
&& test_taint(TAINT_PROPRIETARY_MODULE
))
3246 pr_warn("%s: module license taints kernel.\n", mod
->name
);
3248 #ifdef CONFIG_MODVERSIONS
3249 if ((mod
->num_syms
&& !mod
->crcs
)
3250 || (mod
->num_gpl_syms
&& !mod
->gpl_crcs
)
3251 || (mod
->num_gpl_future_syms
&& !mod
->gpl_future_crcs
)
3252 #ifdef CONFIG_UNUSED_SYMBOLS
3253 || (mod
->num_unused_syms
&& !mod
->unused_crcs
)
3254 || (mod
->num_unused_gpl_syms
&& !mod
->unused_gpl_crcs
)
3257 return try_to_force_load(mod
,
3258 "no versions for exported symbols");
3264 static void flush_module_icache(const struct module
*mod
)
3266 mm_segment_t old_fs
;
3268 /* flush the icache in correct context */
3273 * Flush the instruction cache, since we've played with text.
3274 * Do it before processing of module parameters, so the module
3275 * can provide parameter accessor functions of its own.
3277 if (mod
->init_layout
.base
)
3278 flush_icache_range((unsigned long)mod
->init_layout
.base
,
3279 (unsigned long)mod
->init_layout
.base
3280 + mod
->init_layout
.size
);
3281 flush_icache_range((unsigned long)mod
->core_layout
.base
,
3282 (unsigned long)mod
->core_layout
.base
+ mod
->core_layout
.size
);
3287 int __weak
module_frob_arch_sections(Elf_Ehdr
*hdr
,
3295 /* module_blacklist is a comma-separated list of module names */
3296 static char *module_blacklist
;
3297 static bool blacklisted(const char *module_name
)
3302 if (!module_blacklist
)
3305 for (p
= module_blacklist
; *p
; p
+= len
) {
3306 len
= strcspn(p
, ",");
3307 if (strlen(module_name
) == len
&& !memcmp(module_name
, p
, len
))
3314 core_param(module_blacklist
, module_blacklist
, charp
, 0400);
3316 static struct module
*layout_and_allocate(struct load_info
*info
, int flags
)
3322 err
= check_modinfo(info
->mod
, info
, flags
);
3324 return ERR_PTR(err
);
3326 /* Allow arches to frob section contents and sizes. */
3327 err
= module_frob_arch_sections(info
->hdr
, info
->sechdrs
,
3328 info
->secstrings
, info
->mod
);
3330 return ERR_PTR(err
);
3332 /* We will do a special allocation for per-cpu sections later. */
3333 info
->sechdrs
[info
->index
.pcpu
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
3336 * Mark ro_after_init section with SHF_RO_AFTER_INIT so that
3337 * layout_sections() can put it in the right place.
3338 * Note: ro_after_init sections also have SHF_{WRITE,ALLOC} set.
3340 ndx
= find_sec(info
, ".data..ro_after_init");
3342 info
->sechdrs
[ndx
].sh_flags
|= SHF_RO_AFTER_INIT
;
3344 * Mark the __jump_table section as ro_after_init as well: these data
3345 * structures are never modified, with the exception of entries that
3346 * refer to code in the __init section, which are annotated as such
3347 * at module load time.
3349 ndx
= find_sec(info
, "__jump_table");
3351 info
->sechdrs
[ndx
].sh_flags
|= SHF_RO_AFTER_INIT
;
3353 /* Determine total sizes, and put offsets in sh_entsize. For now
3354 this is done generically; there doesn't appear to be any
3355 special cases for the architectures. */
3356 layout_sections(info
->mod
, info
);
3357 layout_symtab(info
->mod
, info
);
3359 /* Allocate and move to the final place */
3360 err
= move_module(info
->mod
, info
);
3362 return ERR_PTR(err
);
3364 /* Module has been copied to its final place now: return it. */
3365 mod
= (void *)info
->sechdrs
[info
->index
.mod
].sh_addr
;
3366 kmemleak_load_module(mod
, info
);
3370 /* mod is no longer valid after this! */
3371 static void module_deallocate(struct module
*mod
, struct load_info
*info
)
3373 percpu_modfree(mod
);
3374 module_arch_freeing_init(mod
);
3375 module_memfree(mod
->init_layout
.base
);
3376 module_memfree(mod
->core_layout
.base
);
3379 int __weak
module_finalize(const Elf_Ehdr
*hdr
,
3380 const Elf_Shdr
*sechdrs
,
3386 static int post_relocation(struct module
*mod
, const struct load_info
*info
)
3388 /* Sort exception table now relocations are done. */
3389 sort_extable(mod
->extable
, mod
->extable
+ mod
->num_exentries
);
3391 /* Copy relocated percpu area over. */
3392 percpu_modcopy(mod
, (void *)info
->sechdrs
[info
->index
.pcpu
].sh_addr
,
3393 info
->sechdrs
[info
->index
.pcpu
].sh_size
);
3395 /* Setup kallsyms-specific fields. */
3396 add_kallsyms(mod
, info
);
3398 /* Arch-specific module finalizing. */
3399 return module_finalize(info
->hdr
, info
->sechdrs
, mod
);
3402 /* Is this module of this name done loading? No locks held. */
3403 static bool finished_loading(const char *name
)
3409 * The module_mutex should not be a heavily contended lock;
3410 * if we get the occasional sleep here, we'll go an extra iteration
3411 * in the wait_event_interruptible(), which is harmless.
3413 sched_annotate_sleep();
3414 mutex_lock(&module_mutex
);
3415 mod
= find_module_all(name
, strlen(name
), true);
3416 ret
= !mod
|| mod
->state
== MODULE_STATE_LIVE
;
3417 mutex_unlock(&module_mutex
);
3422 /* Call module constructors. */
3423 static void do_mod_ctors(struct module
*mod
)
3425 #ifdef CONFIG_CONSTRUCTORS
3428 for (i
= 0; i
< mod
->num_ctors
; i
++)
3433 /* For freeing module_init on success, in case kallsyms traversing */
3434 struct mod_initfree
{
3435 struct llist_node node
;
3439 static void do_free_init(struct work_struct
*w
)
3441 struct llist_node
*pos
, *n
, *list
;
3442 struct mod_initfree
*initfree
;
3444 list
= llist_del_all(&init_free_list
);
3448 llist_for_each_safe(pos
, n
, list
) {
3449 initfree
= container_of(pos
, struct mod_initfree
, node
);
3450 module_memfree(initfree
->module_init
);
3455 static int __init
modules_wq_init(void)
3457 INIT_WORK(&init_free_wq
, do_free_init
);
3458 init_llist_head(&init_free_list
);
3461 module_init(modules_wq_init
);
3464 * This is where the real work happens.
3466 * Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb
3467 * helper command 'lx-symbols'.
3469 static noinline
int do_init_module(struct module
*mod
)
3472 struct mod_initfree
*freeinit
;
3474 freeinit
= kmalloc(sizeof(*freeinit
), GFP_KERNEL
);
3479 freeinit
->module_init
= mod
->init_layout
.base
;
3482 * We want to find out whether @mod uses async during init. Clear
3483 * PF_USED_ASYNC. async_schedule*() will set it.
3485 current
->flags
&= ~PF_USED_ASYNC
;
3488 /* Start the module */
3489 if (mod
->init
!= NULL
)
3490 ret
= do_one_initcall(mod
->init
);
3492 goto fail_free_freeinit
;
3495 pr_warn("%s: '%s'->init suspiciously returned %d, it should "
3496 "follow 0/-E convention\n"
3497 "%s: loading module anyway...\n",
3498 __func__
, mod
->name
, ret
, __func__
);
3502 /* Now it's a first class citizen! */
3503 mod
->state
= MODULE_STATE_LIVE
;
3504 blocking_notifier_call_chain(&module_notify_list
,
3505 MODULE_STATE_LIVE
, mod
);
3508 * We need to finish all async code before the module init sequence
3509 * is done. This has potential to deadlock. For example, a newly
3510 * detected block device can trigger request_module() of the
3511 * default iosched from async probing task. Once userland helper
3512 * reaches here, async_synchronize_full() will wait on the async
3513 * task waiting on request_module() and deadlock.
3515 * This deadlock is avoided by perfomring async_synchronize_full()
3516 * iff module init queued any async jobs. This isn't a full
3517 * solution as it will deadlock the same if module loading from
3518 * async jobs nests more than once; however, due to the various
3519 * constraints, this hack seems to be the best option for now.
3520 * Please refer to the following thread for details.
3522 * http://thread.gmane.org/gmane.linux.kernel/1420814
3524 if (!mod
->async_probe_requested
&& (current
->flags
& PF_USED_ASYNC
))
3525 async_synchronize_full();
3527 ftrace_free_mem(mod
, mod
->init_layout
.base
, mod
->init_layout
.base
+
3528 mod
->init_layout
.size
);
3529 mutex_lock(&module_mutex
);
3530 /* Drop initial reference. */
3532 trim_init_extable(mod
);
3533 #ifdef CONFIG_KALLSYMS
3534 /* Switch to core kallsyms now init is done: kallsyms may be walking! */
3535 rcu_assign_pointer(mod
->kallsyms
, &mod
->core_kallsyms
);
3537 module_enable_ro(mod
, true);
3538 mod_tree_remove_init(mod
);
3539 module_arch_freeing_init(mod
);
3540 mod
->init_layout
.base
= NULL
;
3541 mod
->init_layout
.size
= 0;
3542 mod
->init_layout
.ro_size
= 0;
3543 mod
->init_layout
.ro_after_init_size
= 0;
3544 mod
->init_layout
.text_size
= 0;
3546 * We want to free module_init, but be aware that kallsyms may be
3547 * walking this with preempt disabled. In all the failure paths, we
3548 * call synchronize_rcu(), but we don't want to slow down the success
3549 * path. module_memfree() cannot be called in an interrupt, so do the
3550 * work and call synchronize_rcu() in a work queue.
3552 * Note that module_alloc() on most architectures creates W+X page
3553 * mappings which won't be cleaned up until do_free_init() runs. Any
3554 * code such as mark_rodata_ro() which depends on those mappings to
3555 * be cleaned up needs to sync with the queued work - ie
3558 if (llist_add(&freeinit
->node
, &init_free_list
))
3559 schedule_work(&init_free_wq
);
3561 mutex_unlock(&module_mutex
);
3562 wake_up_all(&module_wq
);
3569 /* Try to protect us from buggy refcounters. */
3570 mod
->state
= MODULE_STATE_GOING
;
3573 blocking_notifier_call_chain(&module_notify_list
,
3574 MODULE_STATE_GOING
, mod
);
3575 klp_module_going(mod
);
3576 ftrace_release_mod(mod
);
3578 wake_up_all(&module_wq
);
3582 static int may_init_module(void)
3584 if (!capable(CAP_SYS_MODULE
) || modules_disabled
)
3591 * We try to place it in the list now to make sure it's unique before
3592 * we dedicate too many resources. In particular, temporary percpu
3593 * memory exhaustion.
3595 static int add_unformed_module(struct module
*mod
)
3600 mod
->state
= MODULE_STATE_UNFORMED
;
3603 mutex_lock(&module_mutex
);
3604 old
= find_module_all(mod
->name
, strlen(mod
->name
), true);
3606 if (old
->state
!= MODULE_STATE_LIVE
) {
3607 /* Wait in case it fails to load. */
3608 mutex_unlock(&module_mutex
);
3609 err
= wait_event_interruptible(module_wq
,
3610 finished_loading(mod
->name
));
3618 mod_update_bounds(mod
);
3619 list_add_rcu(&mod
->list
, &modules
);
3620 mod_tree_insert(mod
);
3624 mutex_unlock(&module_mutex
);
3629 static int complete_formation(struct module
*mod
, struct load_info
*info
)
3633 mutex_lock(&module_mutex
);
3635 /* Find duplicate symbols (must be called under lock). */
3636 err
= verify_exported_symbols(mod
);
3640 /* This relies on module_mutex for list integrity. */
3641 module_bug_finalize(info
->hdr
, info
->sechdrs
, mod
);
3643 module_enable_ro(mod
, false);
3644 module_enable_nx(mod
);
3645 module_enable_x(mod
);
3647 /* Mark state as coming so strong_try_module_get() ignores us,
3648 * but kallsyms etc. can see us. */
3649 mod
->state
= MODULE_STATE_COMING
;
3650 mutex_unlock(&module_mutex
);
3655 mutex_unlock(&module_mutex
);
3659 static int prepare_coming_module(struct module
*mod
)
3663 ftrace_module_enable(mod
);
3664 err
= klp_module_coming(mod
);
3668 blocking_notifier_call_chain(&module_notify_list
,
3669 MODULE_STATE_COMING
, mod
);
3673 static int unknown_module_param_cb(char *param
, char *val
, const char *modname
,
3676 struct module
*mod
= arg
;
3679 if (strcmp(param
, "async_probe") == 0) {
3680 mod
->async_probe_requested
= true;
3684 /* Check for magic 'dyndbg' arg */
3685 ret
= ddebug_dyndbg_module_param_cb(param
, val
, modname
);
3687 pr_warn("%s: unknown parameter '%s' ignored\n", modname
, param
);
3691 /* Allocate and load the module: note that size of section 0 is always
3692 zero, and we rely on this for optional sections. */
3693 static int load_module(struct load_info
*info
, const char __user
*uargs
,
3700 err
= elf_header_check(info
);
3704 err
= setup_load_info(info
, flags
);
3708 if (blacklisted(info
->name
)) {
3713 err
= module_sig_check(info
, flags
);
3717 err
= rewrite_section_headers(info
, flags
);
3721 /* Check module struct version now, before we try to use module. */
3722 if (!check_modstruct_version(info
, info
->mod
)) {
3727 /* Figure out module layout, and allocate all the memory. */
3728 mod
= layout_and_allocate(info
, flags
);
3734 audit_log_kern_module(mod
->name
);
3736 /* Reserve our place in the list. */
3737 err
= add_unformed_module(mod
);
3741 #ifdef CONFIG_MODULE_SIG
3742 mod
->sig_ok
= info
->sig_ok
;
3744 pr_notice_once("%s: module verification failed: signature "
3745 "and/or required key missing - tainting "
3746 "kernel\n", mod
->name
);
3747 add_taint_module(mod
, TAINT_UNSIGNED_MODULE
, LOCKDEP_STILL_OK
);
3751 /* To avoid stressing percpu allocator, do this once we're unique. */
3752 err
= percpu_modalloc(mod
, info
);
3756 /* Now module is in final location, initialize linked lists, etc. */
3757 err
= module_unload_init(mod
);
3761 init_param_lock(mod
);
3763 /* Now we've got everything in the final locations, we can
3764 * find optional sections. */
3765 err
= find_module_sections(mod
, info
);
3769 err
= check_module_license_and_versions(mod
);
3773 /* Set up MODINFO_ATTR fields */
3774 setup_modinfo(mod
, info
);
3776 /* Fix up syms, so that st_value is a pointer to location. */
3777 err
= simplify_symbols(mod
, info
);
3781 err
= apply_relocations(mod
, info
);
3785 err
= post_relocation(mod
, info
);
3789 flush_module_icache(mod
);
3791 /* Now copy in args */
3792 mod
->args
= strndup_user(uargs
, ~0UL >> 1);
3793 if (IS_ERR(mod
->args
)) {
3794 err
= PTR_ERR(mod
->args
);
3795 goto free_arch_cleanup
;
3798 dynamic_debug_setup(mod
, info
->debug
, info
->num_debug
);
3800 /* Ftrace init must be called in the MODULE_STATE_UNFORMED state */
3801 ftrace_module_init(mod
);
3803 /* Finally it's fully formed, ready to start executing. */
3804 err
= complete_formation(mod
, info
);
3806 goto ddebug_cleanup
;
3808 err
= prepare_coming_module(mod
);
3812 /* Module is ready to execute: parsing args may do that. */
3813 after_dashes
= parse_args(mod
->name
, mod
->args
, mod
->kp
, mod
->num_kp
,
3815 unknown_module_param_cb
);
3816 if (IS_ERR(after_dashes
)) {
3817 err
= PTR_ERR(after_dashes
);
3818 goto coming_cleanup
;
3819 } else if (after_dashes
) {
3820 pr_warn("%s: parameters '%s' after `--' ignored\n",
3821 mod
->name
, after_dashes
);
3824 /* Link in to sysfs. */
3825 err
= mod_sysfs_setup(mod
, info
, mod
->kp
, mod
->num_kp
);
3827 goto coming_cleanup
;
3829 if (is_livepatch_module(mod
)) {
3830 err
= copy_module_elf(mod
, info
);
3835 /* Get rid of temporary copy. */
3839 trace_module_load(mod
);
3841 return do_init_module(mod
);
3844 mod_sysfs_teardown(mod
);
3846 mod
->state
= MODULE_STATE_GOING
;
3847 destroy_params(mod
->kp
, mod
->num_kp
);
3848 blocking_notifier_call_chain(&module_notify_list
,
3849 MODULE_STATE_GOING
, mod
);
3850 klp_module_going(mod
);
3852 /* module_bug_cleanup needs module_mutex protection */
3853 mutex_lock(&module_mutex
);
3854 module_bug_cleanup(mod
);
3855 mutex_unlock(&module_mutex
);
3858 ftrace_release_mod(mod
);
3859 dynamic_debug_remove(mod
, info
->debug
);
3863 module_arch_cleanup(mod
);
3867 module_unload_free(mod
);
3869 mutex_lock(&module_mutex
);
3870 /* Unlink carefully: kallsyms could be walking list. */
3871 list_del_rcu(&mod
->list
);
3872 mod_tree_remove(mod
);
3873 wake_up_all(&module_wq
);
3874 /* Wait for RCU-sched synchronizing before releasing mod->list. */
3876 mutex_unlock(&module_mutex
);
3878 /* Free lock-classes; relies on the preceding sync_rcu() */
3879 lockdep_free_key_range(mod
->core_layout
.base
, mod
->core_layout
.size
);
3881 module_deallocate(mod
, info
);
3887 SYSCALL_DEFINE3(init_module
, void __user
*, umod
,
3888 unsigned long, len
, const char __user
*, uargs
)
3891 struct load_info info
= { };
3893 err
= may_init_module();
3897 pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
3900 err
= copy_module_from_user(umod
, len
, &info
);
3904 return load_module(&info
, uargs
, 0);
3907 SYSCALL_DEFINE3(finit_module
, int, fd
, const char __user
*, uargs
, int, flags
)
3909 struct load_info info
= { };
3914 err
= may_init_module();
3918 pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd
, uargs
, flags
);
3920 if (flags
& ~(MODULE_INIT_IGNORE_MODVERSIONS
3921 |MODULE_INIT_IGNORE_VERMAGIC
))
3924 err
= kernel_read_file_from_fd(fd
, &hdr
, &size
, INT_MAX
,
3931 return load_module(&info
, uargs
, flags
);
3934 static inline int within(unsigned long addr
, void *start
, unsigned long size
)
3936 return ((void *)addr
>= start
&& (void *)addr
< start
+ size
);
3939 #ifdef CONFIG_KALLSYMS
3941 * This ignores the intensely annoying "mapping symbols" found
3942 * in ARM ELF files: $a, $t and $d.
3944 static inline int is_arm_mapping_symbol(const char *str
)
3946 if (str
[0] == '.' && str
[1] == 'L')
3948 return str
[0] == '$' && strchr("axtd", str
[1])
3949 && (str
[2] == '\0' || str
[2] == '.');
3952 static const char *kallsyms_symbol_name(struct mod_kallsyms
*kallsyms
, unsigned int symnum
)
3954 return kallsyms
->strtab
+ kallsyms
->symtab
[symnum
].st_name
;
3958 * Given a module and address, find the corresponding symbol and return its name
3959 * while providing its size and offset if needed.
3961 static const char *find_kallsyms_symbol(struct module
*mod
,
3963 unsigned long *size
,
3964 unsigned long *offset
)
3966 unsigned int i
, best
= 0;
3967 unsigned long nextval
, bestval
;
3968 struct mod_kallsyms
*kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
3970 /* At worse, next value is at end of module */
3971 if (within_module_init(addr
, mod
))
3972 nextval
= (unsigned long)mod
->init_layout
.base
+mod
->init_layout
.text_size
;
3974 nextval
= (unsigned long)mod
->core_layout
.base
+mod
->core_layout
.text_size
;
3976 bestval
= kallsyms_symbol_value(&kallsyms
->symtab
[best
]);
3978 /* Scan for closest preceding symbol, and next symbol. (ELF
3979 starts real symbols at 1). */
3980 for (i
= 1; i
< kallsyms
->num_symtab
; i
++) {
3981 const Elf_Sym
*sym
= &kallsyms
->symtab
[i
];
3982 unsigned long thisval
= kallsyms_symbol_value(sym
);
3984 if (sym
->st_shndx
== SHN_UNDEF
)
3987 /* We ignore unnamed symbols: they're uninformative
3988 * and inserted at a whim. */
3989 if (*kallsyms_symbol_name(kallsyms
, i
) == '\0'
3990 || is_arm_mapping_symbol(kallsyms_symbol_name(kallsyms
, i
)))
3993 if (thisval
<= addr
&& thisval
> bestval
) {
3997 if (thisval
> addr
&& thisval
< nextval
)
4005 *size
= nextval
- bestval
;
4007 *offset
= addr
- bestval
;
4009 return kallsyms_symbol_name(kallsyms
, best
);
4012 void * __weak
dereference_module_function_descriptor(struct module
*mod
,
4018 /* For kallsyms to ask for address resolution. NULL means not found. Careful
4019 * not to lock to avoid deadlock on oopses, simply disable preemption. */
4020 const char *module_address_lookup(unsigned long addr
,
4021 unsigned long *size
,
4022 unsigned long *offset
,
4026 const char *ret
= NULL
;
4030 mod
= __module_address(addr
);
4033 *modname
= mod
->name
;
4035 ret
= find_kallsyms_symbol(mod
, addr
, size
, offset
);
4037 /* Make a copy in here where it's safe */
4039 strncpy(namebuf
, ret
, KSYM_NAME_LEN
- 1);
4047 int lookup_module_symbol_name(unsigned long addr
, char *symname
)
4052 list_for_each_entry_rcu(mod
, &modules
, list
) {
4053 if (mod
->state
== MODULE_STATE_UNFORMED
)
4055 if (within_module(addr
, mod
)) {
4058 sym
= find_kallsyms_symbol(mod
, addr
, NULL
, NULL
);
4062 strlcpy(symname
, sym
, KSYM_NAME_LEN
);
4072 int lookup_module_symbol_attrs(unsigned long addr
, unsigned long *size
,
4073 unsigned long *offset
, char *modname
, char *name
)
4078 list_for_each_entry_rcu(mod
, &modules
, list
) {
4079 if (mod
->state
== MODULE_STATE_UNFORMED
)
4081 if (within_module(addr
, mod
)) {
4084 sym
= find_kallsyms_symbol(mod
, addr
, size
, offset
);
4088 strlcpy(modname
, mod
->name
, MODULE_NAME_LEN
);
4090 strlcpy(name
, sym
, KSYM_NAME_LEN
);
4100 int module_get_kallsym(unsigned int symnum
, unsigned long *value
, char *type
,
4101 char *name
, char *module_name
, int *exported
)
4106 list_for_each_entry_rcu(mod
, &modules
, list
) {
4107 struct mod_kallsyms
*kallsyms
;
4109 if (mod
->state
== MODULE_STATE_UNFORMED
)
4111 kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
4112 if (symnum
< kallsyms
->num_symtab
) {
4113 const Elf_Sym
*sym
= &kallsyms
->symtab
[symnum
];
4115 *value
= kallsyms_symbol_value(sym
);
4116 *type
= kallsyms
->typetab
[symnum
];
4117 strlcpy(name
, kallsyms_symbol_name(kallsyms
, symnum
), KSYM_NAME_LEN
);
4118 strlcpy(module_name
, mod
->name
, MODULE_NAME_LEN
);
4119 *exported
= is_exported(name
, *value
, mod
);
4123 symnum
-= kallsyms
->num_symtab
;
4129 /* Given a module and name of symbol, find and return the symbol's value */
4130 static unsigned long find_kallsyms_symbol_value(struct module
*mod
, const char *name
)
4133 struct mod_kallsyms
*kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
4135 for (i
= 0; i
< kallsyms
->num_symtab
; i
++) {
4136 const Elf_Sym
*sym
= &kallsyms
->symtab
[i
];
4138 if (strcmp(name
, kallsyms_symbol_name(kallsyms
, i
)) == 0 &&
4139 sym
->st_shndx
!= SHN_UNDEF
)
4140 return kallsyms_symbol_value(sym
);
4145 /* Look for this name: can be of form module:name. */
4146 unsigned long module_kallsyms_lookup_name(const char *name
)
4150 unsigned long ret
= 0;
4152 /* Don't lock: we're in enough trouble already. */
4154 if ((colon
= strnchr(name
, MODULE_NAME_LEN
, ':')) != NULL
) {
4155 if ((mod
= find_module_all(name
, colon
- name
, false)) != NULL
)
4156 ret
= find_kallsyms_symbol_value(mod
, colon
+1);
4158 list_for_each_entry_rcu(mod
, &modules
, list
) {
4159 if (mod
->state
== MODULE_STATE_UNFORMED
)
4161 if ((ret
= find_kallsyms_symbol_value(mod
, name
)) != 0)
4169 int module_kallsyms_on_each_symbol(int (*fn
)(void *, const char *,
4170 struct module
*, unsigned long),
4177 module_assert_mutex();
4179 list_for_each_entry(mod
, &modules
, list
) {
4180 /* We hold module_mutex: no need for rcu_dereference_sched */
4181 struct mod_kallsyms
*kallsyms
= mod
->kallsyms
;
4183 if (mod
->state
== MODULE_STATE_UNFORMED
)
4185 for (i
= 0; i
< kallsyms
->num_symtab
; i
++) {
4186 const Elf_Sym
*sym
= &kallsyms
->symtab
[i
];
4188 if (sym
->st_shndx
== SHN_UNDEF
)
4191 ret
= fn(data
, kallsyms_symbol_name(kallsyms
, i
),
4192 mod
, kallsyms_symbol_value(sym
));
4199 #endif /* CONFIG_KALLSYMS */
4201 /* Maximum number of characters written by module_flags() */
4202 #define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4)
4204 /* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */
4205 static char *module_flags(struct module
*mod
, char *buf
)
4209 BUG_ON(mod
->state
== MODULE_STATE_UNFORMED
);
4211 mod
->state
== MODULE_STATE_GOING
||
4212 mod
->state
== MODULE_STATE_COMING
) {
4214 bx
+= module_flags_taint(mod
, buf
+ bx
);
4215 /* Show a - for module-is-being-unloaded */
4216 if (mod
->state
== MODULE_STATE_GOING
)
4218 /* Show a + for module-is-being-loaded */
4219 if (mod
->state
== MODULE_STATE_COMING
)
4228 #ifdef CONFIG_PROC_FS
4229 /* Called by the /proc file system to return a list of modules. */
4230 static void *m_start(struct seq_file
*m
, loff_t
*pos
)
4232 mutex_lock(&module_mutex
);
4233 return seq_list_start(&modules
, *pos
);
4236 static void *m_next(struct seq_file
*m
, void *p
, loff_t
*pos
)
4238 return seq_list_next(p
, &modules
, pos
);
4241 static void m_stop(struct seq_file
*m
, void *p
)
4243 mutex_unlock(&module_mutex
);
4246 static int m_show(struct seq_file
*m
, void *p
)
4248 struct module
*mod
= list_entry(p
, struct module
, list
);
4249 char buf
[MODULE_FLAGS_BUF_SIZE
];
4252 /* We always ignore unformed modules. */
4253 if (mod
->state
== MODULE_STATE_UNFORMED
)
4256 seq_printf(m
, "%s %u",
4257 mod
->name
, mod
->init_layout
.size
+ mod
->core_layout
.size
);
4258 print_unload_info(m
, mod
);
4260 /* Informative for users. */
4261 seq_printf(m
, " %s",
4262 mod
->state
== MODULE_STATE_GOING
? "Unloading" :
4263 mod
->state
== MODULE_STATE_COMING
? "Loading" :
4265 /* Used by oprofile and other similar tools. */
4266 value
= m
->private ? NULL
: mod
->core_layout
.base
;
4267 seq_printf(m
, " 0x%px", value
);
4271 seq_printf(m
, " %s", module_flags(mod
, buf
));
4277 /* Format: modulename size refcount deps address
4279 Where refcount is a number or -, and deps is a comma-separated list
4282 static const struct seq_operations modules_op
= {
4290 * This also sets the "private" pointer to non-NULL if the
4291 * kernel pointers should be hidden (so you can just test
4292 * "m->private" to see if you should keep the values private).
4294 * We use the same logic as for /proc/kallsyms.
4296 static int modules_open(struct inode
*inode
, struct file
*file
)
4298 int err
= seq_open(file
, &modules_op
);
4301 struct seq_file
*m
= file
->private_data
;
4302 m
->private = kallsyms_show_value() ? NULL
: (void *)8ul;
4308 static const struct file_operations proc_modules_operations
= {
4309 .open
= modules_open
,
4311 .llseek
= seq_lseek
,
4312 .release
= seq_release
,
4315 static int __init
proc_modules_init(void)
4317 proc_create("modules", 0, NULL
, &proc_modules_operations
);
4320 module_init(proc_modules_init
);
4323 /* Given an address, look for it in the module exception tables. */
4324 const struct exception_table_entry
*search_module_extables(unsigned long addr
)
4326 const struct exception_table_entry
*e
= NULL
;
4330 mod
= __module_address(addr
);
4334 if (!mod
->num_exentries
)
4337 e
= search_extable(mod
->extable
,
4344 * Now, if we found one, we are running inside it now, hence
4345 * we cannot unload the module, hence no refcnt needed.
4351 * is_module_address - is this address inside a module?
4352 * @addr: the address to check.
4354 * See is_module_text_address() if you simply want to see if the address
4355 * is code (not data).
4357 bool is_module_address(unsigned long addr
)
4362 ret
= __module_address(addr
) != NULL
;
4369 * __module_address - get the module which contains an address.
4370 * @addr: the address.
4372 * Must be called with preempt disabled or module mutex held so that
4373 * module doesn't get freed during this.
4375 struct module
*__module_address(unsigned long addr
)
4379 if (addr
< module_addr_min
|| addr
> module_addr_max
)
4382 module_assert_mutex_or_preempt();
4384 mod
= mod_find(addr
);
4386 BUG_ON(!within_module(addr
, mod
));
4387 if (mod
->state
== MODULE_STATE_UNFORMED
)
4392 EXPORT_SYMBOL_GPL(__module_address
);
4395 * is_module_text_address - is this address inside module code?
4396 * @addr: the address to check.
4398 * See is_module_address() if you simply want to see if the address is
4399 * anywhere in a module. See kernel_text_address() for testing if an
4400 * address corresponds to kernel or module code.
4402 bool is_module_text_address(unsigned long addr
)
4407 ret
= __module_text_address(addr
) != NULL
;
4414 * __module_text_address - get the module whose code contains an address.
4415 * @addr: the address.
4417 * Must be called with preempt disabled or module mutex held so that
4418 * module doesn't get freed during this.
4420 struct module
*__module_text_address(unsigned long addr
)
4422 struct module
*mod
= __module_address(addr
);
4424 /* Make sure it's within the text section. */
4425 if (!within(addr
, mod
->init_layout
.base
, mod
->init_layout
.text_size
)
4426 && !within(addr
, mod
->core_layout
.base
, mod
->core_layout
.text_size
))
4431 EXPORT_SYMBOL_GPL(__module_text_address
);
4433 /* Don't grab lock, we're oopsing. */
4434 void print_modules(void)
4437 char buf
[MODULE_FLAGS_BUF_SIZE
];
4439 printk(KERN_DEFAULT
"Modules linked in:");
4440 /* Most callers should already have preempt disabled, but make sure */
4442 list_for_each_entry_rcu(mod
, &modules
, list
) {
4443 if (mod
->state
== MODULE_STATE_UNFORMED
)
4445 pr_cont(" %s%s", mod
->name
, module_flags(mod
, buf
));
4448 if (last_unloaded_module
[0])
4449 pr_cont(" [last unloaded: %s]", last_unloaded_module
);
4453 #ifdef CONFIG_MODVERSIONS
4454 /* Generate the signature for all relevant module structures here.
4455 * If these change, we don't want to try to parse the module. */
4456 void module_layout(struct module
*mod
,
4457 struct modversion_info
*ver
,
4458 struct kernel_param
*kp
,
4459 struct kernel_symbol
*ks
,
4460 struct tracepoint
* const *tp
)
4463 EXPORT_SYMBOL(module_layout
);