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.
8 #define INCLUDE_VERMAGIC
10 #include <linux/export.h>
11 #include <linux/extable.h>
12 #include <linux/moduleloader.h>
13 #include <linux/module_signature.h>
14 #include <linux/trace_events.h>
15 #include <linux/init.h>
16 #include <linux/kallsyms.h>
17 #include <linux/file.h>
19 #include <linux/sysfs.h>
20 #include <linux/kernel.h>
21 #include <linux/slab.h>
22 #include <linux/vmalloc.h>
23 #include <linux/elf.h>
24 #include <linux/proc_fs.h>
25 #include <linux/security.h>
26 #include <linux/seq_file.h>
27 #include <linux/syscalls.h>
28 #include <linux/fcntl.h>
29 #include <linux/rcupdate.h>
30 #include <linux/capability.h>
31 #include <linux/cpu.h>
32 #include <linux/moduleparam.h>
33 #include <linux/errno.h>
34 #include <linux/err.h>
35 #include <linux/vermagic.h>
36 #include <linux/notifier.h>
37 #include <linux/sched.h>
38 #include <linux/device.h>
39 #include <linux/string.h>
40 #include <linux/mutex.h>
41 #include <linux/rculist.h>
42 #include <linux/uaccess.h>
43 #include <asm/cacheflush.h>
44 #include <linux/set_memory.h>
45 #include <asm/mmu_context.h>
46 #include <linux/license.h>
47 #include <asm/sections.h>
48 #include <linux/tracepoint.h>
49 #include <linux/ftrace.h>
50 #include <linux/livepatch.h>
51 #include <linux/async.h>
52 #include <linux/percpu.h>
53 #include <linux/kmemleak.h>
54 #include <linux/jump_label.h>
55 #include <linux/pfn.h>
56 #include <linux/bsearch.h>
57 #include <linux/dynamic_debug.h>
58 #include <linux/audit.h>
59 #include <uapi/linux/module.h>
60 #include "module-internal.h"
62 #define CREATE_TRACE_POINTS
63 #include <trace/events/module.h>
65 #ifndef ARCH_SHF_SMALL
66 #define ARCH_SHF_SMALL 0
70 * Modules' sections will be aligned on page boundaries
71 * to ensure complete separation of code and data, but
72 * only when CONFIG_ARCH_HAS_STRICT_MODULE_RWX=y
74 #ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX
75 # define debug_align(X) ALIGN(X, PAGE_SIZE)
77 # define debug_align(X) (X)
80 /* If this is set, the section belongs in the init part of the module */
81 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
85 * 1) List of modules (also safely readable with preempt_disable),
86 * 2) module_use links,
87 * 3) module_addr_min/module_addr_max.
88 * (delete and add uses RCU list operations). */
89 DEFINE_MUTEX(module_mutex
);
90 EXPORT_SYMBOL_GPL(module_mutex
);
91 static LIST_HEAD(modules
);
93 /* Work queue for freeing init sections in success case */
94 static struct work_struct init_free_wq
;
95 static struct llist_head init_free_list
;
97 #ifdef CONFIG_MODULES_TREE_LOOKUP
100 * Use a latched RB-tree for __module_address(); this allows us to use
101 * RCU-sched lookups of the address from any context.
103 * This is conditional on PERF_EVENTS || TRACING because those can really hit
104 * __module_address() hard by doing a lot of stack unwinding; potentially from
108 static __always_inline
unsigned long __mod_tree_val(struct latch_tree_node
*n
)
110 struct module_layout
*layout
= container_of(n
, struct module_layout
, mtn
.node
);
112 return (unsigned long)layout
->base
;
115 static __always_inline
unsigned long __mod_tree_size(struct latch_tree_node
*n
)
117 struct module_layout
*layout
= container_of(n
, struct module_layout
, mtn
.node
);
119 return (unsigned long)layout
->size
;
122 static __always_inline
bool
123 mod_tree_less(struct latch_tree_node
*a
, struct latch_tree_node
*b
)
125 return __mod_tree_val(a
) < __mod_tree_val(b
);
128 static __always_inline
int
129 mod_tree_comp(void *key
, struct latch_tree_node
*n
)
131 unsigned long val
= (unsigned long)key
;
132 unsigned long start
, end
;
134 start
= __mod_tree_val(n
);
138 end
= start
+ __mod_tree_size(n
);
145 static const struct latch_tree_ops mod_tree_ops
= {
146 .less
= mod_tree_less
,
147 .comp
= mod_tree_comp
,
150 static struct mod_tree_root
{
151 struct latch_tree_root root
;
152 unsigned long addr_min
;
153 unsigned long addr_max
;
154 } mod_tree __cacheline_aligned
= {
158 #define module_addr_min mod_tree.addr_min
159 #define module_addr_max mod_tree.addr_max
161 static noinline
void __mod_tree_insert(struct mod_tree_node
*node
)
163 latch_tree_insert(&node
->node
, &mod_tree
.root
, &mod_tree_ops
);
166 static void __mod_tree_remove(struct mod_tree_node
*node
)
168 latch_tree_erase(&node
->node
, &mod_tree
.root
, &mod_tree_ops
);
172 * These modifications: insert, remove_init and remove; are serialized by the
175 static void mod_tree_insert(struct module
*mod
)
177 mod
->core_layout
.mtn
.mod
= mod
;
178 mod
->init_layout
.mtn
.mod
= mod
;
180 __mod_tree_insert(&mod
->core_layout
.mtn
);
181 if (mod
->init_layout
.size
)
182 __mod_tree_insert(&mod
->init_layout
.mtn
);
185 static void mod_tree_remove_init(struct module
*mod
)
187 if (mod
->init_layout
.size
)
188 __mod_tree_remove(&mod
->init_layout
.mtn
);
191 static void mod_tree_remove(struct module
*mod
)
193 __mod_tree_remove(&mod
->core_layout
.mtn
);
194 mod_tree_remove_init(mod
);
197 static struct module
*mod_find(unsigned long addr
)
199 struct latch_tree_node
*ltn
;
201 ltn
= latch_tree_find((void *)addr
, &mod_tree
.root
, &mod_tree_ops
);
205 return container_of(ltn
, struct mod_tree_node
, node
)->mod
;
208 #else /* MODULES_TREE_LOOKUP */
210 static unsigned long module_addr_min
= -1UL, module_addr_max
= 0;
212 static void mod_tree_insert(struct module
*mod
) { }
213 static void mod_tree_remove_init(struct module
*mod
) { }
214 static void mod_tree_remove(struct module
*mod
) { }
216 static struct module
*mod_find(unsigned long addr
)
220 list_for_each_entry_rcu(mod
, &modules
, list
,
221 lockdep_is_held(&module_mutex
)) {
222 if (within_module(addr
, mod
))
229 #endif /* MODULES_TREE_LOOKUP */
232 * Bounds of module text, for speeding up __module_address.
233 * Protected by module_mutex.
235 static void __mod_update_bounds(void *base
, unsigned int size
)
237 unsigned long min
= (unsigned long)base
;
238 unsigned long max
= min
+ size
;
240 if (min
< module_addr_min
)
241 module_addr_min
= min
;
242 if (max
> module_addr_max
)
243 module_addr_max
= max
;
246 static void mod_update_bounds(struct module
*mod
)
248 __mod_update_bounds(mod
->core_layout
.base
, mod
->core_layout
.size
);
249 if (mod
->init_layout
.size
)
250 __mod_update_bounds(mod
->init_layout
.base
, mod
->init_layout
.size
);
253 #ifdef CONFIG_KGDB_KDB
254 struct list_head
*kdb_modules
= &modules
; /* kdb needs the list of modules */
255 #endif /* CONFIG_KGDB_KDB */
257 static void module_assert_mutex(void)
259 lockdep_assert_held(&module_mutex
);
262 static void module_assert_mutex_or_preempt(void)
264 #ifdef CONFIG_LOCKDEP
265 if (unlikely(!debug_locks
))
268 WARN_ON_ONCE(!rcu_read_lock_sched_held() &&
269 !lockdep_is_held(&module_mutex
));
273 static bool sig_enforce
= IS_ENABLED(CONFIG_MODULE_SIG_FORCE
);
274 module_param(sig_enforce
, bool_enable_only
, 0644);
277 * Export sig_enforce kernel cmdline parameter to allow other subsystems rely
278 * on that instead of directly to CONFIG_MODULE_SIG_FORCE config.
280 bool is_module_sig_enforced(void)
284 EXPORT_SYMBOL(is_module_sig_enforced
);
286 void set_module_sig_enforced(void)
291 /* Block module loading/unloading? */
292 int modules_disabled
= 0;
293 core_param(nomodule
, modules_disabled
, bint
, 0);
295 /* Waiting for a module to finish initializing? */
296 static DECLARE_WAIT_QUEUE_HEAD(module_wq
);
298 static BLOCKING_NOTIFIER_HEAD(module_notify_list
);
300 int register_module_notifier(struct notifier_block
*nb
)
302 return blocking_notifier_chain_register(&module_notify_list
, nb
);
304 EXPORT_SYMBOL(register_module_notifier
);
306 int unregister_module_notifier(struct notifier_block
*nb
)
308 return blocking_notifier_chain_unregister(&module_notify_list
, nb
);
310 EXPORT_SYMBOL(unregister_module_notifier
);
313 * We require a truly strong try_module_get(): 0 means success.
314 * Otherwise an error is returned due to ongoing or failed
315 * initialization etc.
317 static inline int strong_try_module_get(struct module
*mod
)
319 BUG_ON(mod
&& mod
->state
== MODULE_STATE_UNFORMED
);
320 if (mod
&& mod
->state
== MODULE_STATE_COMING
)
322 if (try_module_get(mod
))
328 static inline void add_taint_module(struct module
*mod
, unsigned flag
,
329 enum lockdep_ok lockdep_ok
)
331 add_taint(flag
, lockdep_ok
);
332 set_bit(flag
, &mod
->taints
);
336 * A thread that wants to hold a reference to a module only while it
337 * is running can call this to safely exit. nfsd and lockd use this.
339 void __noreturn
__module_put_and_exit(struct module
*mod
, long code
)
344 EXPORT_SYMBOL(__module_put_and_exit
);
346 /* Find a module section: 0 means not found. */
347 static unsigned int find_sec(const struct load_info
*info
, const char *name
)
351 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
352 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
353 /* Alloc bit cleared means "ignore it." */
354 if ((shdr
->sh_flags
& SHF_ALLOC
)
355 && strcmp(info
->secstrings
+ shdr
->sh_name
, name
) == 0)
361 /* Find a module section, or NULL. */
362 static void *section_addr(const struct load_info
*info
, const char *name
)
364 /* Section 0 has sh_addr 0. */
365 return (void *)info
->sechdrs
[find_sec(info
, name
)].sh_addr
;
368 /* Find a module section, or NULL. Fill in number of "objects" in section. */
369 static void *section_objs(const struct load_info
*info
,
374 unsigned int sec
= find_sec(info
, name
);
376 /* Section 0 has sh_addr 0 and sh_size 0. */
377 *num
= info
->sechdrs
[sec
].sh_size
/ object_size
;
378 return (void *)info
->sechdrs
[sec
].sh_addr
;
381 /* Provided by the linker */
382 extern const struct kernel_symbol __start___ksymtab
[];
383 extern const struct kernel_symbol __stop___ksymtab
[];
384 extern const struct kernel_symbol __start___ksymtab_gpl
[];
385 extern const struct kernel_symbol __stop___ksymtab_gpl
[];
386 extern const struct kernel_symbol __start___ksymtab_gpl_future
[];
387 extern const struct kernel_symbol __stop___ksymtab_gpl_future
[];
388 extern const s32 __start___kcrctab
[];
389 extern const s32 __start___kcrctab_gpl
[];
390 extern const s32 __start___kcrctab_gpl_future
[];
391 #ifdef CONFIG_UNUSED_SYMBOLS
392 extern const struct kernel_symbol __start___ksymtab_unused
[];
393 extern const struct kernel_symbol __stop___ksymtab_unused
[];
394 extern const struct kernel_symbol __start___ksymtab_unused_gpl
[];
395 extern const struct kernel_symbol __stop___ksymtab_unused_gpl
[];
396 extern const s32 __start___kcrctab_unused
[];
397 extern const s32 __start___kcrctab_unused_gpl
[];
400 #ifndef CONFIG_MODVERSIONS
401 #define symversion(base, idx) NULL
403 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
406 static bool each_symbol_in_section(const struct symsearch
*arr
,
407 unsigned int arrsize
,
408 struct module
*owner
,
409 bool (*fn
)(const struct symsearch
*syms
,
410 struct module
*owner
,
416 for (j
= 0; j
< arrsize
; j
++) {
417 if (fn(&arr
[j
], owner
, data
))
424 /* Returns true as soon as fn returns true, otherwise false. */
425 bool each_symbol_section(bool (*fn
)(const struct symsearch
*arr
,
426 struct module
*owner
,
431 static const struct symsearch arr
[] = {
432 { __start___ksymtab
, __stop___ksymtab
, __start___kcrctab
,
433 NOT_GPL_ONLY
, false },
434 { __start___ksymtab_gpl
, __stop___ksymtab_gpl
,
435 __start___kcrctab_gpl
,
437 { __start___ksymtab_gpl_future
, __stop___ksymtab_gpl_future
,
438 __start___kcrctab_gpl_future
,
439 WILL_BE_GPL_ONLY
, false },
440 #ifdef CONFIG_UNUSED_SYMBOLS
441 { __start___ksymtab_unused
, __stop___ksymtab_unused
,
442 __start___kcrctab_unused
,
443 NOT_GPL_ONLY
, true },
444 { __start___ksymtab_unused_gpl
, __stop___ksymtab_unused_gpl
,
445 __start___kcrctab_unused_gpl
,
450 module_assert_mutex_or_preempt();
452 if (each_symbol_in_section(arr
, ARRAY_SIZE(arr
), NULL
, fn
, data
))
455 list_for_each_entry_rcu(mod
, &modules
, list
,
456 lockdep_is_held(&module_mutex
)) {
457 struct symsearch arr
[] = {
458 { mod
->syms
, mod
->syms
+ mod
->num_syms
, mod
->crcs
,
459 NOT_GPL_ONLY
, false },
460 { mod
->gpl_syms
, mod
->gpl_syms
+ mod
->num_gpl_syms
,
463 { mod
->gpl_future_syms
,
464 mod
->gpl_future_syms
+ mod
->num_gpl_future_syms
,
465 mod
->gpl_future_crcs
,
466 WILL_BE_GPL_ONLY
, false },
467 #ifdef CONFIG_UNUSED_SYMBOLS
469 mod
->unused_syms
+ mod
->num_unused_syms
,
471 NOT_GPL_ONLY
, true },
472 { mod
->unused_gpl_syms
,
473 mod
->unused_gpl_syms
+ mod
->num_unused_gpl_syms
,
474 mod
->unused_gpl_crcs
,
479 if (mod
->state
== MODULE_STATE_UNFORMED
)
482 if (each_symbol_in_section(arr
, ARRAY_SIZE(arr
), mod
, fn
, data
))
487 EXPORT_SYMBOL_GPL(each_symbol_section
);
489 struct find_symbol_arg
{
496 struct module
*owner
;
498 const struct kernel_symbol
*sym
;
501 static bool check_exported_symbol(const struct symsearch
*syms
,
502 struct module
*owner
,
503 unsigned int symnum
, void *data
)
505 struct find_symbol_arg
*fsa
= data
;
508 if (syms
->licence
== GPL_ONLY
)
510 if (syms
->licence
== WILL_BE_GPL_ONLY
&& fsa
->warn
) {
511 pr_warn("Symbol %s is being used by a non-GPL module, "
512 "which will not be allowed in the future\n",
517 #ifdef CONFIG_UNUSED_SYMBOLS
518 if (syms
->unused
&& fsa
->warn
) {
519 pr_warn("Symbol %s is marked as UNUSED, however this module is "
520 "using it.\n", fsa
->name
);
521 pr_warn("This symbol will go away in the future.\n");
522 pr_warn("Please evaluate if this is the right api to use and "
523 "if it really is, submit a report to the linux kernel "
524 "mailing list together with submitting your code for "
530 fsa
->crc
= symversion(syms
->crcs
, symnum
);
531 fsa
->sym
= &syms
->start
[symnum
];
535 static unsigned long kernel_symbol_value(const struct kernel_symbol
*sym
)
537 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
538 return (unsigned long)offset_to_ptr(&sym
->value_offset
);
544 static const char *kernel_symbol_name(const struct kernel_symbol
*sym
)
546 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
547 return offset_to_ptr(&sym
->name_offset
);
553 static const char *kernel_symbol_namespace(const struct kernel_symbol
*sym
)
555 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
556 if (!sym
->namespace_offset
)
558 return offset_to_ptr(&sym
->namespace_offset
);
560 return sym
->namespace;
564 static int cmp_name(const void *name
, const void *sym
)
566 return strcmp(name
, kernel_symbol_name(sym
));
569 static bool find_exported_symbol_in_section(const struct symsearch
*syms
,
570 struct module
*owner
,
573 struct find_symbol_arg
*fsa
= data
;
574 struct kernel_symbol
*sym
;
576 sym
= bsearch(fsa
->name
, syms
->start
, syms
->stop
- syms
->start
,
577 sizeof(struct kernel_symbol
), cmp_name
);
579 if (sym
!= NULL
&& check_exported_symbol(syms
, owner
,
580 sym
- syms
->start
, data
))
586 /* Find an exported symbol and return it, along with, (optional) crc and
587 * (optional) module which owns it. Needs preempt disabled or module_mutex. */
588 const struct kernel_symbol
*find_symbol(const char *name
,
589 struct module
**owner
,
594 struct find_symbol_arg fsa
;
600 if (each_symbol_section(find_exported_symbol_in_section
, &fsa
)) {
608 pr_debug("Failed to find symbol %s\n", name
);
611 EXPORT_SYMBOL_GPL(find_symbol
);
614 * Search for module by name: must hold module_mutex (or preempt disabled
615 * for read-only access).
617 static struct module
*find_module_all(const char *name
, size_t len
,
622 module_assert_mutex_or_preempt();
624 list_for_each_entry_rcu(mod
, &modules
, list
,
625 lockdep_is_held(&module_mutex
)) {
626 if (!even_unformed
&& mod
->state
== MODULE_STATE_UNFORMED
)
628 if (strlen(mod
->name
) == len
&& !memcmp(mod
->name
, name
, len
))
634 struct module
*find_module(const char *name
)
636 module_assert_mutex();
637 return find_module_all(name
, strlen(name
), false);
639 EXPORT_SYMBOL_GPL(find_module
);
643 static inline void __percpu
*mod_percpu(struct module
*mod
)
648 static int percpu_modalloc(struct module
*mod
, struct load_info
*info
)
650 Elf_Shdr
*pcpusec
= &info
->sechdrs
[info
->index
.pcpu
];
651 unsigned long align
= pcpusec
->sh_addralign
;
653 if (!pcpusec
->sh_size
)
656 if (align
> PAGE_SIZE
) {
657 pr_warn("%s: per-cpu alignment %li > %li\n",
658 mod
->name
, align
, PAGE_SIZE
);
662 mod
->percpu
= __alloc_reserved_percpu(pcpusec
->sh_size
, align
);
664 pr_warn("%s: Could not allocate %lu bytes percpu data\n",
665 mod
->name
, (unsigned long)pcpusec
->sh_size
);
668 mod
->percpu_size
= pcpusec
->sh_size
;
672 static void percpu_modfree(struct module
*mod
)
674 free_percpu(mod
->percpu
);
677 static unsigned int find_pcpusec(struct load_info
*info
)
679 return find_sec(info
, ".data..percpu");
682 static void percpu_modcopy(struct module
*mod
,
683 const void *from
, unsigned long size
)
687 for_each_possible_cpu(cpu
)
688 memcpy(per_cpu_ptr(mod
->percpu
, cpu
), from
, size
);
691 bool __is_module_percpu_address(unsigned long addr
, unsigned long *can_addr
)
698 list_for_each_entry_rcu(mod
, &modules
, list
) {
699 if (mod
->state
== MODULE_STATE_UNFORMED
)
701 if (!mod
->percpu_size
)
703 for_each_possible_cpu(cpu
) {
704 void *start
= per_cpu_ptr(mod
->percpu
, cpu
);
705 void *va
= (void *)addr
;
707 if (va
>= start
&& va
< start
+ mod
->percpu_size
) {
709 *can_addr
= (unsigned long) (va
- start
);
710 *can_addr
+= (unsigned long)
711 per_cpu_ptr(mod
->percpu
,
725 * is_module_percpu_address - test whether address is from module static percpu
726 * @addr: address to test
728 * Test whether @addr belongs to module static percpu area.
731 * %true if @addr is from module static percpu area
733 bool is_module_percpu_address(unsigned long addr
)
735 return __is_module_percpu_address(addr
, NULL
);
738 #else /* ... !CONFIG_SMP */
740 static inline void __percpu
*mod_percpu(struct module
*mod
)
744 static int percpu_modalloc(struct module
*mod
, struct load_info
*info
)
746 /* UP modules shouldn't have this section: ENOMEM isn't quite right */
747 if (info
->sechdrs
[info
->index
.pcpu
].sh_size
!= 0)
751 static inline void percpu_modfree(struct module
*mod
)
754 static unsigned int find_pcpusec(struct load_info
*info
)
758 static inline void percpu_modcopy(struct module
*mod
,
759 const void *from
, unsigned long size
)
761 /* pcpusec should be 0, and size of that section should be 0. */
764 bool is_module_percpu_address(unsigned long addr
)
769 bool __is_module_percpu_address(unsigned long addr
, unsigned long *can_addr
)
774 #endif /* CONFIG_SMP */
776 #define MODINFO_ATTR(field) \
777 static void setup_modinfo_##field(struct module *mod, const char *s) \
779 mod->field = kstrdup(s, GFP_KERNEL); \
781 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
782 struct module_kobject *mk, char *buffer) \
784 return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \
786 static int modinfo_##field##_exists(struct module *mod) \
788 return mod->field != NULL; \
790 static void free_modinfo_##field(struct module *mod) \
795 static struct module_attribute modinfo_##field = { \
796 .attr = { .name = __stringify(field), .mode = 0444 }, \
797 .show = show_modinfo_##field, \
798 .setup = setup_modinfo_##field, \
799 .test = modinfo_##field##_exists, \
800 .free = free_modinfo_##field, \
803 MODINFO_ATTR(version
);
804 MODINFO_ATTR(srcversion
);
806 static char last_unloaded_module
[MODULE_NAME_LEN
+1];
808 #ifdef CONFIG_MODULE_UNLOAD
810 EXPORT_TRACEPOINT_SYMBOL(module_get
);
812 /* MODULE_REF_BASE is the base reference count by kmodule loader. */
813 #define MODULE_REF_BASE 1
815 /* Init the unload section of the module. */
816 static int module_unload_init(struct module
*mod
)
819 * Initialize reference counter to MODULE_REF_BASE.
820 * refcnt == 0 means module is going.
822 atomic_set(&mod
->refcnt
, MODULE_REF_BASE
);
824 INIT_LIST_HEAD(&mod
->source_list
);
825 INIT_LIST_HEAD(&mod
->target_list
);
827 /* Hold reference count during initialization. */
828 atomic_inc(&mod
->refcnt
);
833 /* Does a already use b? */
834 static int already_uses(struct module
*a
, struct module
*b
)
836 struct module_use
*use
;
838 list_for_each_entry(use
, &b
->source_list
, source_list
) {
839 if (use
->source
== a
) {
840 pr_debug("%s uses %s!\n", a
->name
, b
->name
);
844 pr_debug("%s does not use %s!\n", a
->name
, b
->name
);
850 * - we add 'a' as a "source", 'b' as a "target" of module use
851 * - the module_use is added to the list of 'b' sources (so
852 * 'b' can walk the list to see who sourced them), and of 'a'
853 * targets (so 'a' can see what modules it targets).
855 static int add_module_usage(struct module
*a
, struct module
*b
)
857 struct module_use
*use
;
859 pr_debug("Allocating new usage for %s.\n", a
->name
);
860 use
= kmalloc(sizeof(*use
), GFP_ATOMIC
);
866 list_add(&use
->source_list
, &b
->source_list
);
867 list_add(&use
->target_list
, &a
->target_list
);
871 /* Module a uses b: caller needs module_mutex() */
872 int ref_module(struct module
*a
, struct module
*b
)
876 if (b
== NULL
|| already_uses(a
, b
))
879 /* If module isn't available, we fail. */
880 err
= strong_try_module_get(b
);
884 err
= add_module_usage(a
, b
);
891 EXPORT_SYMBOL_GPL(ref_module
);
893 /* Clear the unload stuff of the module. */
894 static void module_unload_free(struct module
*mod
)
896 struct module_use
*use
, *tmp
;
898 mutex_lock(&module_mutex
);
899 list_for_each_entry_safe(use
, tmp
, &mod
->target_list
, target_list
) {
900 struct module
*i
= use
->target
;
901 pr_debug("%s unusing %s\n", mod
->name
, i
->name
);
903 list_del(&use
->source_list
);
904 list_del(&use
->target_list
);
907 mutex_unlock(&module_mutex
);
910 #ifdef CONFIG_MODULE_FORCE_UNLOAD
911 static inline int try_force_unload(unsigned int flags
)
913 int ret
= (flags
& O_TRUNC
);
915 add_taint(TAINT_FORCED_RMMOD
, LOCKDEP_NOW_UNRELIABLE
);
919 static inline int try_force_unload(unsigned int flags
)
923 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
925 /* Try to release refcount of module, 0 means success. */
926 static int try_release_module_ref(struct module
*mod
)
930 /* Try to decrement refcnt which we set at loading */
931 ret
= atomic_sub_return(MODULE_REF_BASE
, &mod
->refcnt
);
934 /* Someone can put this right now, recover with checking */
935 ret
= atomic_add_unless(&mod
->refcnt
, MODULE_REF_BASE
, 0);
940 static int try_stop_module(struct module
*mod
, int flags
, int *forced
)
942 /* If it's not unused, quit unless we're forcing. */
943 if (try_release_module_ref(mod
) != 0) {
944 *forced
= try_force_unload(flags
);
949 /* Mark it as dying. */
950 mod
->state
= MODULE_STATE_GOING
;
956 * module_refcount - return the refcount or -1 if unloading
958 * @mod: the module we're checking
961 * -1 if the module is in the process of unloading
962 * otherwise the number of references in the kernel to the module
964 int module_refcount(struct module
*mod
)
966 return atomic_read(&mod
->refcnt
) - MODULE_REF_BASE
;
968 EXPORT_SYMBOL(module_refcount
);
970 /* This exists whether we can unload or not */
971 static void free_module(struct module
*mod
);
973 SYSCALL_DEFINE2(delete_module
, const char __user
*, name_user
,
977 char name
[MODULE_NAME_LEN
];
980 if (!capable(CAP_SYS_MODULE
) || modules_disabled
)
983 if (strncpy_from_user(name
, name_user
, MODULE_NAME_LEN
-1) < 0)
985 name
[MODULE_NAME_LEN
-1] = '\0';
987 audit_log_kern_module(name
);
989 if (mutex_lock_interruptible(&module_mutex
) != 0)
992 mod
= find_module(name
);
998 if (!list_empty(&mod
->source_list
)) {
999 /* Other modules depend on us: get rid of them first. */
1004 /* Doing init or already dying? */
1005 if (mod
->state
!= MODULE_STATE_LIVE
) {
1006 /* FIXME: if (force), slam module count damn the torpedoes */
1007 pr_debug("%s already dying\n", mod
->name
);
1012 /* If it has an init func, it must have an exit func to unload */
1013 if (mod
->init
&& !mod
->exit
) {
1014 forced
= try_force_unload(flags
);
1016 /* This module can't be removed */
1022 /* Stop the machine so refcounts can't move and disable module. */
1023 ret
= try_stop_module(mod
, flags
, &forced
);
1027 mutex_unlock(&module_mutex
);
1028 /* Final destruction now no one is using it. */
1029 if (mod
->exit
!= NULL
)
1031 blocking_notifier_call_chain(&module_notify_list
,
1032 MODULE_STATE_GOING
, mod
);
1033 klp_module_going(mod
);
1034 ftrace_release_mod(mod
);
1036 async_synchronize_full();
1038 /* Store the name of the last unloaded module for diagnostic purposes */
1039 strlcpy(last_unloaded_module
, mod
->name
, sizeof(last_unloaded_module
));
1042 /* someone could wait for the module in add_unformed_module() */
1043 wake_up_all(&module_wq
);
1046 mutex_unlock(&module_mutex
);
1050 static inline void print_unload_info(struct seq_file
*m
, struct module
*mod
)
1052 struct module_use
*use
;
1053 int printed_something
= 0;
1055 seq_printf(m
, " %i ", module_refcount(mod
));
1058 * Always include a trailing , so userspace can differentiate
1059 * between this and the old multi-field proc format.
1061 list_for_each_entry(use
, &mod
->source_list
, source_list
) {
1062 printed_something
= 1;
1063 seq_printf(m
, "%s,", use
->source
->name
);
1066 if (mod
->init
!= NULL
&& mod
->exit
== NULL
) {
1067 printed_something
= 1;
1068 seq_puts(m
, "[permanent],");
1071 if (!printed_something
)
1075 void __symbol_put(const char *symbol
)
1077 struct module
*owner
;
1080 if (!find_symbol(symbol
, &owner
, NULL
, true, false))
1085 EXPORT_SYMBOL(__symbol_put
);
1087 /* Note this assumes addr is a function, which it currently always is. */
1088 void symbol_put_addr(void *addr
)
1090 struct module
*modaddr
;
1091 unsigned long a
= (unsigned long)dereference_function_descriptor(addr
);
1093 if (core_kernel_text(a
))
1097 * Even though we hold a reference on the module; we still need to
1098 * disable preemption in order to safely traverse the data structure.
1101 modaddr
= __module_text_address(a
);
1103 module_put(modaddr
);
1106 EXPORT_SYMBOL_GPL(symbol_put_addr
);
1108 static ssize_t
show_refcnt(struct module_attribute
*mattr
,
1109 struct module_kobject
*mk
, char *buffer
)
1111 return sprintf(buffer
, "%i\n", module_refcount(mk
->mod
));
1114 static struct module_attribute modinfo_refcnt
=
1115 __ATTR(refcnt
, 0444, show_refcnt
, NULL
);
1117 void __module_get(struct module
*module
)
1121 atomic_inc(&module
->refcnt
);
1122 trace_module_get(module
, _RET_IP_
);
1126 EXPORT_SYMBOL(__module_get
);
1128 bool try_module_get(struct module
*module
)
1134 /* Note: here, we can fail to get a reference */
1135 if (likely(module_is_live(module
) &&
1136 atomic_inc_not_zero(&module
->refcnt
) != 0))
1137 trace_module_get(module
, _RET_IP_
);
1145 EXPORT_SYMBOL(try_module_get
);
1147 void module_put(struct module
*module
)
1153 ret
= atomic_dec_if_positive(&module
->refcnt
);
1154 WARN_ON(ret
< 0); /* Failed to put refcount */
1155 trace_module_put(module
, _RET_IP_
);
1159 EXPORT_SYMBOL(module_put
);
1161 #else /* !CONFIG_MODULE_UNLOAD */
1162 static inline void print_unload_info(struct seq_file
*m
, struct module
*mod
)
1164 /* We don't know the usage count, or what modules are using. */
1165 seq_puts(m
, " - -");
1168 static inline void module_unload_free(struct module
*mod
)
1172 int ref_module(struct module
*a
, struct module
*b
)
1174 return strong_try_module_get(b
);
1176 EXPORT_SYMBOL_GPL(ref_module
);
1178 static inline int module_unload_init(struct module
*mod
)
1182 #endif /* CONFIG_MODULE_UNLOAD */
1184 static size_t module_flags_taint(struct module
*mod
, char *buf
)
1189 for (i
= 0; i
< TAINT_FLAGS_COUNT
; i
++) {
1190 if (taint_flags
[i
].module
&& test_bit(i
, &mod
->taints
))
1191 buf
[l
++] = taint_flags
[i
].c_true
;
1197 static ssize_t
show_initstate(struct module_attribute
*mattr
,
1198 struct module_kobject
*mk
, char *buffer
)
1200 const char *state
= "unknown";
1202 switch (mk
->mod
->state
) {
1203 case MODULE_STATE_LIVE
:
1206 case MODULE_STATE_COMING
:
1209 case MODULE_STATE_GOING
:
1215 return sprintf(buffer
, "%s\n", state
);
1218 static struct module_attribute modinfo_initstate
=
1219 __ATTR(initstate
, 0444, show_initstate
, NULL
);
1221 static ssize_t
store_uevent(struct module_attribute
*mattr
,
1222 struct module_kobject
*mk
,
1223 const char *buffer
, size_t count
)
1227 rc
= kobject_synth_uevent(&mk
->kobj
, buffer
, count
);
1228 return rc
? rc
: count
;
1231 struct module_attribute module_uevent
=
1232 __ATTR(uevent
, 0200, NULL
, store_uevent
);
1234 static ssize_t
show_coresize(struct module_attribute
*mattr
,
1235 struct module_kobject
*mk
, char *buffer
)
1237 return sprintf(buffer
, "%u\n", mk
->mod
->core_layout
.size
);
1240 static struct module_attribute modinfo_coresize
=
1241 __ATTR(coresize
, 0444, show_coresize
, NULL
);
1243 static ssize_t
show_initsize(struct module_attribute
*mattr
,
1244 struct module_kobject
*mk
, char *buffer
)
1246 return sprintf(buffer
, "%u\n", mk
->mod
->init_layout
.size
);
1249 static struct module_attribute modinfo_initsize
=
1250 __ATTR(initsize
, 0444, show_initsize
, NULL
);
1252 static ssize_t
show_taint(struct module_attribute
*mattr
,
1253 struct module_kobject
*mk
, char *buffer
)
1257 l
= module_flags_taint(mk
->mod
, buffer
);
1262 static struct module_attribute modinfo_taint
=
1263 __ATTR(taint
, 0444, show_taint
, NULL
);
1265 static struct module_attribute
*modinfo_attrs
[] = {
1268 &modinfo_srcversion
,
1273 #ifdef CONFIG_MODULE_UNLOAD
1279 static const char vermagic
[] = VERMAGIC_STRING
;
1281 static int try_to_force_load(struct module
*mod
, const char *reason
)
1283 #ifdef CONFIG_MODULE_FORCE_LOAD
1284 if (!test_taint(TAINT_FORCED_MODULE
))
1285 pr_warn("%s: %s: kernel tainted.\n", mod
->name
, reason
);
1286 add_taint_module(mod
, TAINT_FORCED_MODULE
, LOCKDEP_NOW_UNRELIABLE
);
1293 #ifdef CONFIG_MODVERSIONS
1295 static u32
resolve_rel_crc(const s32
*crc
)
1297 return *(u32
*)((void *)crc
+ *crc
);
1300 static int check_version(const struct load_info
*info
,
1301 const char *symname
,
1305 Elf_Shdr
*sechdrs
= info
->sechdrs
;
1306 unsigned int versindex
= info
->index
.vers
;
1307 unsigned int i
, num_versions
;
1308 struct modversion_info
*versions
;
1310 /* Exporting module didn't supply crcs? OK, we're already tainted. */
1314 /* No versions at all? modprobe --force does this. */
1316 return try_to_force_load(mod
, symname
) == 0;
1318 versions
= (void *) sechdrs
[versindex
].sh_addr
;
1319 num_versions
= sechdrs
[versindex
].sh_size
1320 / sizeof(struct modversion_info
);
1322 for (i
= 0; i
< num_versions
; i
++) {
1325 if (strcmp(versions
[i
].name
, symname
) != 0)
1328 if (IS_ENABLED(CONFIG_MODULE_REL_CRCS
))
1329 crcval
= resolve_rel_crc(crc
);
1332 if (versions
[i
].crc
== crcval
)
1334 pr_debug("Found checksum %X vs module %lX\n",
1335 crcval
, versions
[i
].crc
);
1339 /* Broken toolchain. Warn once, then let it go.. */
1340 pr_warn_once("%s: no symbol version for %s\n", info
->name
, symname
);
1344 pr_warn("%s: disagrees about version of symbol %s\n",
1345 info
->name
, symname
);
1349 static inline int check_modstruct_version(const struct load_info
*info
,
1355 * Since this should be found in kernel (which can't be removed), no
1356 * locking is necessary -- use preempt_disable() to placate lockdep.
1359 if (!find_symbol("module_layout", NULL
, &crc
, true, false)) {
1364 return check_version(info
, "module_layout", mod
, crc
);
1367 /* First part is kernel version, which we ignore if module has crcs. */
1368 static inline int same_magic(const char *amagic
, const char *bmagic
,
1372 amagic
+= strcspn(amagic
, " ");
1373 bmagic
+= strcspn(bmagic
, " ");
1375 return strcmp(amagic
, bmagic
) == 0;
1378 static inline int check_version(const struct load_info
*info
,
1379 const char *symname
,
1386 static inline int check_modstruct_version(const struct load_info
*info
,
1392 static inline int same_magic(const char *amagic
, const char *bmagic
,
1395 return strcmp(amagic
, bmagic
) == 0;
1397 #endif /* CONFIG_MODVERSIONS */
1399 static char *get_modinfo(const struct load_info
*info
, const char *tag
);
1400 static char *get_next_modinfo(const struct load_info
*info
, const char *tag
,
1403 static int verify_namespace_is_imported(const struct load_info
*info
,
1404 const struct kernel_symbol
*sym
,
1407 const char *namespace;
1408 char *imported_namespace
;
1410 namespace = kernel_symbol_namespace(sym
);
1411 if (namespace && namespace[0]) {
1412 imported_namespace
= get_modinfo(info
, "import_ns");
1413 while (imported_namespace
) {
1414 if (strcmp(namespace, imported_namespace
) == 0)
1416 imported_namespace
= get_next_modinfo(
1417 info
, "import_ns", imported_namespace
);
1419 #ifdef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS
1424 "%s: module uses symbol (%s) from namespace %s, but does not import it.\n",
1425 mod
->name
, kernel_symbol_name(sym
), namespace);
1426 #ifndef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS
1434 /* Resolve a symbol for this module. I.e. if we find one, record usage. */
1435 static const struct kernel_symbol
*resolve_symbol(struct module
*mod
,
1436 const struct load_info
*info
,
1440 struct module
*owner
;
1441 const struct kernel_symbol
*sym
;
1446 * The module_mutex should not be a heavily contended lock;
1447 * if we get the occasional sleep here, we'll go an extra iteration
1448 * in the wait_event_interruptible(), which is harmless.
1450 sched_annotate_sleep();
1451 mutex_lock(&module_mutex
);
1452 sym
= find_symbol(name
, &owner
, &crc
,
1453 !(mod
->taints
& (1 << TAINT_PROPRIETARY_MODULE
)), true);
1457 if (!check_version(info
, name
, mod
, crc
)) {
1458 sym
= ERR_PTR(-EINVAL
);
1462 err
= verify_namespace_is_imported(info
, sym
, mod
);
1468 err
= ref_module(mod
, owner
);
1475 /* We must make copy under the lock if we failed to get ref. */
1476 strncpy(ownername
, module_name(owner
), MODULE_NAME_LEN
);
1478 mutex_unlock(&module_mutex
);
1482 static const struct kernel_symbol
*
1483 resolve_symbol_wait(struct module
*mod
,
1484 const struct load_info
*info
,
1487 const struct kernel_symbol
*ksym
;
1488 char owner
[MODULE_NAME_LEN
];
1490 if (wait_event_interruptible_timeout(module_wq
,
1491 !IS_ERR(ksym
= resolve_symbol(mod
, info
, name
, owner
))
1492 || PTR_ERR(ksym
) != -EBUSY
,
1494 pr_warn("%s: gave up waiting for init of module %s.\n",
1501 * /sys/module/foo/sections stuff
1502 * J. Corbet <corbet@lwn.net>
1506 #ifdef CONFIG_KALLSYMS
1507 static inline bool sect_empty(const Elf_Shdr
*sect
)
1509 return !(sect
->sh_flags
& SHF_ALLOC
) || sect
->sh_size
== 0;
1512 struct module_sect_attr
{
1513 struct module_attribute mattr
;
1515 unsigned long address
;
1518 struct module_sect_attrs
{
1519 struct attribute_group grp
;
1520 unsigned int nsections
;
1521 struct module_sect_attr attrs
[];
1524 static ssize_t
module_sect_show(struct module_attribute
*mattr
,
1525 struct module_kobject
*mk
, char *buf
)
1527 struct module_sect_attr
*sattr
=
1528 container_of(mattr
, struct module_sect_attr
, mattr
);
1529 return sprintf(buf
, "0x%px\n", kptr_restrict
< 2 ?
1530 (void *)sattr
->address
: NULL
);
1533 static void free_sect_attrs(struct module_sect_attrs
*sect_attrs
)
1535 unsigned int section
;
1537 for (section
= 0; section
< sect_attrs
->nsections
; section
++)
1538 kfree(sect_attrs
->attrs
[section
].name
);
1542 static void add_sect_attrs(struct module
*mod
, const struct load_info
*info
)
1544 unsigned int nloaded
= 0, i
, size
[2];
1545 struct module_sect_attrs
*sect_attrs
;
1546 struct module_sect_attr
*sattr
;
1547 struct attribute
**gattr
;
1549 /* Count loaded sections and allocate structures */
1550 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
1551 if (!sect_empty(&info
->sechdrs
[i
]))
1553 size
[0] = ALIGN(struct_size(sect_attrs
, attrs
, nloaded
),
1554 sizeof(sect_attrs
->grp
.attrs
[0]));
1555 size
[1] = (nloaded
+ 1) * sizeof(sect_attrs
->grp
.attrs
[0]);
1556 sect_attrs
= kzalloc(size
[0] + size
[1], GFP_KERNEL
);
1557 if (sect_attrs
== NULL
)
1560 /* Setup section attributes. */
1561 sect_attrs
->grp
.name
= "sections";
1562 sect_attrs
->grp
.attrs
= (void *)sect_attrs
+ size
[0];
1564 sect_attrs
->nsections
= 0;
1565 sattr
= §_attrs
->attrs
[0];
1566 gattr
= §_attrs
->grp
.attrs
[0];
1567 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++) {
1568 Elf_Shdr
*sec
= &info
->sechdrs
[i
];
1569 if (sect_empty(sec
))
1571 sattr
->address
= sec
->sh_addr
;
1572 sattr
->name
= kstrdup(info
->secstrings
+ sec
->sh_name
,
1574 if (sattr
->name
== NULL
)
1576 sect_attrs
->nsections
++;
1577 sysfs_attr_init(&sattr
->mattr
.attr
);
1578 sattr
->mattr
.show
= module_sect_show
;
1579 sattr
->mattr
.store
= NULL
;
1580 sattr
->mattr
.attr
.name
= sattr
->name
;
1581 sattr
->mattr
.attr
.mode
= S_IRUSR
;
1582 *(gattr
++) = &(sattr
++)->mattr
.attr
;
1586 if (sysfs_create_group(&mod
->mkobj
.kobj
, §_attrs
->grp
))
1589 mod
->sect_attrs
= sect_attrs
;
1592 free_sect_attrs(sect_attrs
);
1595 static void remove_sect_attrs(struct module
*mod
)
1597 if (mod
->sect_attrs
) {
1598 sysfs_remove_group(&mod
->mkobj
.kobj
,
1599 &mod
->sect_attrs
->grp
);
1600 /* We are positive that no one is using any sect attrs
1601 * at this point. Deallocate immediately. */
1602 free_sect_attrs(mod
->sect_attrs
);
1603 mod
->sect_attrs
= NULL
;
1608 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1611 struct module_notes_attrs
{
1612 struct kobject
*dir
;
1614 struct bin_attribute attrs
[];
1617 static ssize_t
module_notes_read(struct file
*filp
, struct kobject
*kobj
,
1618 struct bin_attribute
*bin_attr
,
1619 char *buf
, loff_t pos
, size_t count
)
1622 * The caller checked the pos and count against our size.
1624 memcpy(buf
, bin_attr
->private + pos
, count
);
1628 static void free_notes_attrs(struct module_notes_attrs
*notes_attrs
,
1631 if (notes_attrs
->dir
) {
1633 sysfs_remove_bin_file(notes_attrs
->dir
,
1634 ¬es_attrs
->attrs
[i
]);
1635 kobject_put(notes_attrs
->dir
);
1640 static void add_notes_attrs(struct module
*mod
, const struct load_info
*info
)
1642 unsigned int notes
, loaded
, i
;
1643 struct module_notes_attrs
*notes_attrs
;
1644 struct bin_attribute
*nattr
;
1646 /* failed to create section attributes, so can't create notes */
1647 if (!mod
->sect_attrs
)
1650 /* Count notes sections and allocate structures. */
1652 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
1653 if (!sect_empty(&info
->sechdrs
[i
]) &&
1654 (info
->sechdrs
[i
].sh_type
== SHT_NOTE
))
1660 notes_attrs
= kzalloc(struct_size(notes_attrs
, attrs
, notes
),
1662 if (notes_attrs
== NULL
)
1665 notes_attrs
->notes
= notes
;
1666 nattr
= ¬es_attrs
->attrs
[0];
1667 for (loaded
= i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
1668 if (sect_empty(&info
->sechdrs
[i
]))
1670 if (info
->sechdrs
[i
].sh_type
== SHT_NOTE
) {
1671 sysfs_bin_attr_init(nattr
);
1672 nattr
->attr
.name
= mod
->sect_attrs
->attrs
[loaded
].name
;
1673 nattr
->attr
.mode
= S_IRUGO
;
1674 nattr
->size
= info
->sechdrs
[i
].sh_size
;
1675 nattr
->private = (void *) info
->sechdrs
[i
].sh_addr
;
1676 nattr
->read
= module_notes_read
;
1682 notes_attrs
->dir
= kobject_create_and_add("notes", &mod
->mkobj
.kobj
);
1683 if (!notes_attrs
->dir
)
1686 for (i
= 0; i
< notes
; ++i
)
1687 if (sysfs_create_bin_file(notes_attrs
->dir
,
1688 ¬es_attrs
->attrs
[i
]))
1691 mod
->notes_attrs
= notes_attrs
;
1695 free_notes_attrs(notes_attrs
, i
);
1698 static void remove_notes_attrs(struct module
*mod
)
1700 if (mod
->notes_attrs
)
1701 free_notes_attrs(mod
->notes_attrs
, mod
->notes_attrs
->notes
);
1706 static inline void add_sect_attrs(struct module
*mod
,
1707 const struct load_info
*info
)
1711 static inline void remove_sect_attrs(struct module
*mod
)
1715 static inline void add_notes_attrs(struct module
*mod
,
1716 const struct load_info
*info
)
1720 static inline void remove_notes_attrs(struct module
*mod
)
1723 #endif /* CONFIG_KALLSYMS */
1725 static void del_usage_links(struct module
*mod
)
1727 #ifdef CONFIG_MODULE_UNLOAD
1728 struct module_use
*use
;
1730 mutex_lock(&module_mutex
);
1731 list_for_each_entry(use
, &mod
->target_list
, target_list
)
1732 sysfs_remove_link(use
->target
->holders_dir
, mod
->name
);
1733 mutex_unlock(&module_mutex
);
1737 static int add_usage_links(struct module
*mod
)
1740 #ifdef CONFIG_MODULE_UNLOAD
1741 struct module_use
*use
;
1743 mutex_lock(&module_mutex
);
1744 list_for_each_entry(use
, &mod
->target_list
, target_list
) {
1745 ret
= sysfs_create_link(use
->target
->holders_dir
,
1746 &mod
->mkobj
.kobj
, mod
->name
);
1750 mutex_unlock(&module_mutex
);
1752 del_usage_links(mod
);
1757 static void module_remove_modinfo_attrs(struct module
*mod
, int end
);
1759 static int module_add_modinfo_attrs(struct module
*mod
)
1761 struct module_attribute
*attr
;
1762 struct module_attribute
*temp_attr
;
1766 mod
->modinfo_attrs
= kzalloc((sizeof(struct module_attribute
) *
1767 (ARRAY_SIZE(modinfo_attrs
) + 1)),
1769 if (!mod
->modinfo_attrs
)
1772 temp_attr
= mod
->modinfo_attrs
;
1773 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
1774 if (!attr
->test
|| attr
->test(mod
)) {
1775 memcpy(temp_attr
, attr
, sizeof(*temp_attr
));
1776 sysfs_attr_init(&temp_attr
->attr
);
1777 error
= sysfs_create_file(&mod
->mkobj
.kobj
,
1789 module_remove_modinfo_attrs(mod
, --i
);
1791 kfree(mod
->modinfo_attrs
);
1795 static void module_remove_modinfo_attrs(struct module
*mod
, int end
)
1797 struct module_attribute
*attr
;
1800 for (i
= 0; (attr
= &mod
->modinfo_attrs
[i
]); i
++) {
1801 if (end
>= 0 && i
> end
)
1803 /* pick a field to test for end of list */
1804 if (!attr
->attr
.name
)
1806 sysfs_remove_file(&mod
->mkobj
.kobj
, &attr
->attr
);
1810 kfree(mod
->modinfo_attrs
);
1813 static void mod_kobject_put(struct module
*mod
)
1815 DECLARE_COMPLETION_ONSTACK(c
);
1816 mod
->mkobj
.kobj_completion
= &c
;
1817 kobject_put(&mod
->mkobj
.kobj
);
1818 wait_for_completion(&c
);
1821 static int mod_sysfs_init(struct module
*mod
)
1824 struct kobject
*kobj
;
1826 if (!module_sysfs_initialized
) {
1827 pr_err("%s: module sysfs not initialized\n", mod
->name
);
1832 kobj
= kset_find_obj(module_kset
, mod
->name
);
1834 pr_err("%s: module is already loaded\n", mod
->name
);
1840 mod
->mkobj
.mod
= mod
;
1842 memset(&mod
->mkobj
.kobj
, 0, sizeof(mod
->mkobj
.kobj
));
1843 mod
->mkobj
.kobj
.kset
= module_kset
;
1844 err
= kobject_init_and_add(&mod
->mkobj
.kobj
, &module_ktype
, NULL
,
1847 mod_kobject_put(mod
);
1849 /* delay uevent until full sysfs population */
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
)
1861 err
= mod_sysfs_init(mod
);
1865 mod
->holders_dir
= kobject_create_and_add("holders", &mod
->mkobj
.kobj
);
1866 if (!mod
->holders_dir
) {
1871 err
= module_param_sysfs_setup(mod
, kparam
, num_params
);
1873 goto out_unreg_holders
;
1875 err
= module_add_modinfo_attrs(mod
);
1877 goto out_unreg_param
;
1879 err
= add_usage_links(mod
);
1881 goto out_unreg_modinfo_attrs
;
1883 add_sect_attrs(mod
, info
);
1884 add_notes_attrs(mod
, info
);
1886 kobject_uevent(&mod
->mkobj
.kobj
, KOBJ_ADD
);
1889 out_unreg_modinfo_attrs
:
1890 module_remove_modinfo_attrs(mod
, -1);
1892 module_param_sysfs_remove(mod
);
1894 kobject_put(mod
->holders_dir
);
1896 mod_kobject_put(mod
);
1901 static void mod_sysfs_fini(struct module
*mod
)
1903 remove_notes_attrs(mod
);
1904 remove_sect_attrs(mod
);
1905 mod_kobject_put(mod
);
1908 static void init_param_lock(struct module
*mod
)
1910 mutex_init(&mod
->param_lock
);
1912 #else /* !CONFIG_SYSFS */
1914 static int mod_sysfs_setup(struct module
*mod
,
1915 const struct load_info
*info
,
1916 struct kernel_param
*kparam
,
1917 unsigned int num_params
)
1922 static void mod_sysfs_fini(struct module
*mod
)
1926 static void module_remove_modinfo_attrs(struct module
*mod
, int end
)
1930 static void del_usage_links(struct module
*mod
)
1934 static void init_param_lock(struct module
*mod
)
1937 #endif /* CONFIG_SYSFS */
1939 static void mod_sysfs_teardown(struct module
*mod
)
1941 del_usage_links(mod
);
1942 module_remove_modinfo_attrs(mod
, -1);
1943 module_param_sysfs_remove(mod
);
1944 kobject_put(mod
->mkobj
.drivers_dir
);
1945 kobject_put(mod
->holders_dir
);
1946 mod_sysfs_fini(mod
);
1949 #ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX
1951 * LKM RO/NX protection: protect module's text/ro-data
1952 * from modification and any data from execution.
1954 * General layout of module is:
1955 * [text] [read-only-data] [ro-after-init] [writable data]
1956 * text_size -----^ ^ ^ ^
1957 * ro_size ------------------------| | |
1958 * ro_after_init_size -----------------------------| |
1959 * size -----------------------------------------------------------|
1961 * These values are always page-aligned (as is base)
1963 static void frob_text(const struct module_layout
*layout
,
1964 int (*set_memory
)(unsigned long start
, int num_pages
))
1966 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1967 BUG_ON((unsigned long)layout
->text_size
& (PAGE_SIZE
-1));
1968 set_memory((unsigned long)layout
->base
,
1969 layout
->text_size
>> PAGE_SHIFT
);
1972 #ifdef CONFIG_STRICT_MODULE_RWX
1973 static void frob_rodata(const struct module_layout
*layout
,
1974 int (*set_memory
)(unsigned long start
, int num_pages
))
1976 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1977 BUG_ON((unsigned long)layout
->text_size
& (PAGE_SIZE
-1));
1978 BUG_ON((unsigned long)layout
->ro_size
& (PAGE_SIZE
-1));
1979 set_memory((unsigned long)layout
->base
+ layout
->text_size
,
1980 (layout
->ro_size
- layout
->text_size
) >> PAGE_SHIFT
);
1983 static void frob_ro_after_init(const struct module_layout
*layout
,
1984 int (*set_memory
)(unsigned long start
, int num_pages
))
1986 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1987 BUG_ON((unsigned long)layout
->ro_size
& (PAGE_SIZE
-1));
1988 BUG_ON((unsigned long)layout
->ro_after_init_size
& (PAGE_SIZE
-1));
1989 set_memory((unsigned long)layout
->base
+ layout
->ro_size
,
1990 (layout
->ro_after_init_size
- layout
->ro_size
) >> PAGE_SHIFT
);
1993 static void frob_writable_data(const struct module_layout
*layout
,
1994 int (*set_memory
)(unsigned long start
, int num_pages
))
1996 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1997 BUG_ON((unsigned long)layout
->ro_after_init_size
& (PAGE_SIZE
-1));
1998 BUG_ON((unsigned long)layout
->size
& (PAGE_SIZE
-1));
1999 set_memory((unsigned long)layout
->base
+ layout
->ro_after_init_size
,
2000 (layout
->size
- layout
->ro_after_init_size
) >> PAGE_SHIFT
);
2003 static void module_enable_ro(const struct module
*mod
, bool after_init
)
2005 if (!rodata_enabled
)
2008 set_vm_flush_reset_perms(mod
->core_layout
.base
);
2009 set_vm_flush_reset_perms(mod
->init_layout
.base
);
2010 frob_text(&mod
->core_layout
, set_memory_ro
);
2012 frob_rodata(&mod
->core_layout
, set_memory_ro
);
2013 frob_text(&mod
->init_layout
, set_memory_ro
);
2014 frob_rodata(&mod
->init_layout
, set_memory_ro
);
2017 frob_ro_after_init(&mod
->core_layout
, set_memory_ro
);
2020 static void module_enable_nx(const struct module
*mod
)
2022 frob_rodata(&mod
->core_layout
, set_memory_nx
);
2023 frob_ro_after_init(&mod
->core_layout
, set_memory_nx
);
2024 frob_writable_data(&mod
->core_layout
, set_memory_nx
);
2025 frob_rodata(&mod
->init_layout
, set_memory_nx
);
2026 frob_writable_data(&mod
->init_layout
, set_memory_nx
);
2029 #else /* !CONFIG_STRICT_MODULE_RWX */
2030 static void module_enable_nx(const struct module
*mod
) { }
2031 static void module_enable_ro(const struct module
*mod
, bool after_init
) {}
2032 #endif /* CONFIG_STRICT_MODULE_RWX */
2033 static void module_enable_x(const struct module
*mod
)
2035 frob_text(&mod
->core_layout
, set_memory_x
);
2036 frob_text(&mod
->init_layout
, set_memory_x
);
2038 #else /* !CONFIG_ARCH_HAS_STRICT_MODULE_RWX */
2039 static void module_enable_nx(const struct module
*mod
) { }
2040 static void module_enable_x(const struct module
*mod
) { }
2041 #endif /* CONFIG_ARCH_HAS_STRICT_MODULE_RWX */
2044 #ifdef CONFIG_LIVEPATCH
2046 * Persist Elf information about a module. Copy the Elf header,
2047 * section header table, section string table, and symtab section
2048 * index from info to mod->klp_info.
2050 static int copy_module_elf(struct module
*mod
, struct load_info
*info
)
2052 unsigned int size
, symndx
;
2055 size
= sizeof(*mod
->klp_info
);
2056 mod
->klp_info
= kmalloc(size
, GFP_KERNEL
);
2057 if (mod
->klp_info
== NULL
)
2061 size
= sizeof(mod
->klp_info
->hdr
);
2062 memcpy(&mod
->klp_info
->hdr
, info
->hdr
, size
);
2064 /* Elf section header table */
2065 size
= sizeof(*info
->sechdrs
) * info
->hdr
->e_shnum
;
2066 mod
->klp_info
->sechdrs
= kmemdup(info
->sechdrs
, size
, GFP_KERNEL
);
2067 if (mod
->klp_info
->sechdrs
== NULL
) {
2072 /* Elf section name string table */
2073 size
= info
->sechdrs
[info
->hdr
->e_shstrndx
].sh_size
;
2074 mod
->klp_info
->secstrings
= kmemdup(info
->secstrings
, size
, GFP_KERNEL
);
2075 if (mod
->klp_info
->secstrings
== NULL
) {
2080 /* Elf symbol section index */
2081 symndx
= info
->index
.sym
;
2082 mod
->klp_info
->symndx
= symndx
;
2085 * For livepatch modules, core_kallsyms.symtab is a complete
2086 * copy of the original symbol table. Adjust sh_addr to point
2087 * to core_kallsyms.symtab since the copy of the symtab in module
2088 * init memory is freed at the end of do_init_module().
2090 mod
->klp_info
->sechdrs
[symndx
].sh_addr
= \
2091 (unsigned long) mod
->core_kallsyms
.symtab
;
2096 kfree(mod
->klp_info
->sechdrs
);
2098 kfree(mod
->klp_info
);
2102 static void free_module_elf(struct module
*mod
)
2104 kfree(mod
->klp_info
->sechdrs
);
2105 kfree(mod
->klp_info
->secstrings
);
2106 kfree(mod
->klp_info
);
2108 #else /* !CONFIG_LIVEPATCH */
2109 static int copy_module_elf(struct module
*mod
, struct load_info
*info
)
2114 static void free_module_elf(struct module
*mod
)
2117 #endif /* CONFIG_LIVEPATCH */
2119 void __weak
module_memfree(void *module_region
)
2122 * This memory may be RO, and freeing RO memory in an interrupt is not
2123 * supported by vmalloc.
2125 WARN_ON(in_interrupt());
2126 vfree(module_region
);
2129 void __weak
module_arch_cleanup(struct module
*mod
)
2133 void __weak
module_arch_freeing_init(struct module
*mod
)
2137 /* Free a module, remove from lists, etc. */
2138 static void free_module(struct module
*mod
)
2140 trace_module_free(mod
);
2142 mod_sysfs_teardown(mod
);
2144 /* We leave it in list to prevent duplicate loads, but make sure
2145 * that noone uses it while it's being deconstructed. */
2146 mutex_lock(&module_mutex
);
2147 mod
->state
= MODULE_STATE_UNFORMED
;
2148 mutex_unlock(&module_mutex
);
2150 /* Remove dynamic debug info */
2151 ddebug_remove_module(mod
->name
);
2153 /* Arch-specific cleanup. */
2154 module_arch_cleanup(mod
);
2156 /* Module unload stuff */
2157 module_unload_free(mod
);
2159 /* Free any allocated parameters. */
2160 destroy_params(mod
->kp
, mod
->num_kp
);
2162 if (is_livepatch_module(mod
))
2163 free_module_elf(mod
);
2165 /* Now we can delete it from the lists */
2166 mutex_lock(&module_mutex
);
2167 /* Unlink carefully: kallsyms could be walking list. */
2168 list_del_rcu(&mod
->list
);
2169 mod_tree_remove(mod
);
2170 /* Remove this module from bug list, this uses list_del_rcu */
2171 module_bug_cleanup(mod
);
2172 /* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */
2174 mutex_unlock(&module_mutex
);
2176 /* This may be empty, but that's OK */
2177 module_arch_freeing_init(mod
);
2178 module_memfree(mod
->init_layout
.base
);
2180 percpu_modfree(mod
);
2182 /* Free lock-classes; relies on the preceding sync_rcu(). */
2183 lockdep_free_key_range(mod
->core_layout
.base
, mod
->core_layout
.size
);
2185 /* Finally, free the core (containing the module structure) */
2186 module_memfree(mod
->core_layout
.base
);
2189 void *__symbol_get(const char *symbol
)
2191 struct module
*owner
;
2192 const struct kernel_symbol
*sym
;
2195 sym
= find_symbol(symbol
, &owner
, NULL
, true, true);
2196 if (sym
&& strong_try_module_get(owner
))
2200 return sym
? (void *)kernel_symbol_value(sym
) : NULL
;
2202 EXPORT_SYMBOL_GPL(__symbol_get
);
2205 * Ensure that an exported symbol [global namespace] does not already exist
2206 * in the kernel or in some other module's exported symbol table.
2208 * You must hold the module_mutex.
2210 static int verify_exported_symbols(struct module
*mod
)
2213 struct module
*owner
;
2214 const struct kernel_symbol
*s
;
2216 const struct kernel_symbol
*sym
;
2219 { mod
->syms
, mod
->num_syms
},
2220 { mod
->gpl_syms
, mod
->num_gpl_syms
},
2221 { mod
->gpl_future_syms
, mod
->num_gpl_future_syms
},
2222 #ifdef CONFIG_UNUSED_SYMBOLS
2223 { mod
->unused_syms
, mod
->num_unused_syms
},
2224 { mod
->unused_gpl_syms
, mod
->num_unused_gpl_syms
},
2228 for (i
= 0; i
< ARRAY_SIZE(arr
); i
++) {
2229 for (s
= arr
[i
].sym
; s
< arr
[i
].sym
+ arr
[i
].num
; s
++) {
2230 if (find_symbol(kernel_symbol_name(s
), &owner
, NULL
,
2232 pr_err("%s: exports duplicate symbol %s"
2234 mod
->name
, kernel_symbol_name(s
),
2235 module_name(owner
));
2243 /* Change all symbols so that st_value encodes the pointer directly. */
2244 static int simplify_symbols(struct module
*mod
, const struct load_info
*info
)
2246 Elf_Shdr
*symsec
= &info
->sechdrs
[info
->index
.sym
];
2247 Elf_Sym
*sym
= (void *)symsec
->sh_addr
;
2248 unsigned long secbase
;
2251 const struct kernel_symbol
*ksym
;
2253 for (i
= 1; i
< symsec
->sh_size
/ sizeof(Elf_Sym
); i
++) {
2254 const char *name
= info
->strtab
+ sym
[i
].st_name
;
2256 switch (sym
[i
].st_shndx
) {
2258 /* Ignore common symbols */
2259 if (!strncmp(name
, "__gnu_lto", 9))
2262 /* We compiled with -fno-common. These are not
2263 supposed to happen. */
2264 pr_debug("Common symbol: %s\n", name
);
2265 pr_warn("%s: please compile with -fno-common\n",
2271 /* Don't need to do anything */
2272 pr_debug("Absolute symbol: 0x%08lx\n",
2273 (long)sym
[i
].st_value
);
2277 /* Livepatch symbols are resolved by livepatch */
2281 ksym
= resolve_symbol_wait(mod
, info
, name
);
2282 /* Ok if resolved. */
2283 if (ksym
&& !IS_ERR(ksym
)) {
2284 sym
[i
].st_value
= kernel_symbol_value(ksym
);
2289 if (!ksym
&& ELF_ST_BIND(sym
[i
].st_info
) == STB_WEAK
)
2292 ret
= PTR_ERR(ksym
) ?: -ENOENT
;
2293 pr_warn("%s: Unknown symbol %s (err %d)\n",
2294 mod
->name
, name
, ret
);
2298 /* Divert to percpu allocation if a percpu var. */
2299 if (sym
[i
].st_shndx
== info
->index
.pcpu
)
2300 secbase
= (unsigned long)mod_percpu(mod
);
2302 secbase
= info
->sechdrs
[sym
[i
].st_shndx
].sh_addr
;
2303 sym
[i
].st_value
+= secbase
;
2311 static int apply_relocations(struct module
*mod
, const struct load_info
*info
)
2316 /* Now do relocations. */
2317 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2318 unsigned int infosec
= info
->sechdrs
[i
].sh_info
;
2320 /* Not a valid relocation section? */
2321 if (infosec
>= info
->hdr
->e_shnum
)
2324 /* Don't bother with non-allocated sections */
2325 if (!(info
->sechdrs
[infosec
].sh_flags
& SHF_ALLOC
))
2328 if (info
->sechdrs
[i
].sh_flags
& SHF_RELA_LIVEPATCH
)
2329 err
= klp_apply_section_relocs(mod
, info
->sechdrs
,
2334 else if (info
->sechdrs
[i
].sh_type
== SHT_REL
)
2335 err
= apply_relocate(info
->sechdrs
, info
->strtab
,
2336 info
->index
.sym
, i
, mod
);
2337 else if (info
->sechdrs
[i
].sh_type
== SHT_RELA
)
2338 err
= apply_relocate_add(info
->sechdrs
, info
->strtab
,
2339 info
->index
.sym
, i
, mod
);
2346 /* Additional bytes needed by arch in front of individual sections */
2347 unsigned int __weak
arch_mod_section_prepend(struct module
*mod
,
2348 unsigned int section
)
2350 /* default implementation just returns zero */
2354 /* Update size with this section: return offset. */
2355 static long get_offset(struct module
*mod
, unsigned int *size
,
2356 Elf_Shdr
*sechdr
, unsigned int section
)
2360 *size
+= arch_mod_section_prepend(mod
, section
);
2361 ret
= ALIGN(*size
, sechdr
->sh_addralign
?: 1);
2362 *size
= ret
+ sechdr
->sh_size
;
2366 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
2367 might -- code, read-only data, read-write data, small data. Tally
2368 sizes, and place the offsets into sh_entsize fields: high bit means it
2370 static void layout_sections(struct module
*mod
, struct load_info
*info
)
2372 static unsigned long const masks
[][2] = {
2373 /* NOTE: all executable code must be the first section
2374 * in this array; otherwise modify the text_size
2375 * finder in the two loops below */
2376 { SHF_EXECINSTR
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2377 { SHF_ALLOC
, SHF_WRITE
| ARCH_SHF_SMALL
},
2378 { SHF_RO_AFTER_INIT
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2379 { SHF_WRITE
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2380 { ARCH_SHF_SMALL
| SHF_ALLOC
, 0 }
2384 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
2385 info
->sechdrs
[i
].sh_entsize
= ~0UL;
2387 pr_debug("Core section allocation order:\n");
2388 for (m
= 0; m
< ARRAY_SIZE(masks
); ++m
) {
2389 for (i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
2390 Elf_Shdr
*s
= &info
->sechdrs
[i
];
2391 const char *sname
= info
->secstrings
+ s
->sh_name
;
2393 if ((s
->sh_flags
& masks
[m
][0]) != masks
[m
][0]
2394 || (s
->sh_flags
& masks
[m
][1])
2395 || s
->sh_entsize
!= ~0UL
2396 || module_init_section(sname
))
2398 s
->sh_entsize
= get_offset(mod
, &mod
->core_layout
.size
, s
, i
);
2399 pr_debug("\t%s\n", sname
);
2402 case 0: /* executable */
2403 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2404 mod
->core_layout
.text_size
= mod
->core_layout
.size
;
2406 case 1: /* RO: text and ro-data */
2407 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2408 mod
->core_layout
.ro_size
= mod
->core_layout
.size
;
2410 case 2: /* RO after init */
2411 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2412 mod
->core_layout
.ro_after_init_size
= mod
->core_layout
.size
;
2414 case 4: /* whole core */
2415 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2420 pr_debug("Init section allocation order:\n");
2421 for (m
= 0; m
< ARRAY_SIZE(masks
); ++m
) {
2422 for (i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
2423 Elf_Shdr
*s
= &info
->sechdrs
[i
];
2424 const char *sname
= info
->secstrings
+ s
->sh_name
;
2426 if ((s
->sh_flags
& masks
[m
][0]) != masks
[m
][0]
2427 || (s
->sh_flags
& masks
[m
][1])
2428 || s
->sh_entsize
!= ~0UL
2429 || !module_init_section(sname
))
2431 s
->sh_entsize
= (get_offset(mod
, &mod
->init_layout
.size
, s
, i
)
2432 | INIT_OFFSET_MASK
);
2433 pr_debug("\t%s\n", sname
);
2436 case 0: /* executable */
2437 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2438 mod
->init_layout
.text_size
= mod
->init_layout
.size
;
2440 case 1: /* RO: text and ro-data */
2441 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2442 mod
->init_layout
.ro_size
= mod
->init_layout
.size
;
2446 * RO after init doesn't apply to init_layout (only
2447 * core_layout), so it just takes the value of ro_size.
2449 mod
->init_layout
.ro_after_init_size
= mod
->init_layout
.ro_size
;
2451 case 4: /* whole init */
2452 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2458 static void set_license(struct module
*mod
, const char *license
)
2461 license
= "unspecified";
2463 if (!license_is_gpl_compatible(license
)) {
2464 if (!test_taint(TAINT_PROPRIETARY_MODULE
))
2465 pr_warn("%s: module license '%s' taints kernel.\n",
2466 mod
->name
, license
);
2467 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
2468 LOCKDEP_NOW_UNRELIABLE
);
2472 /* Parse tag=value strings from .modinfo section */
2473 static char *next_string(char *string
, unsigned long *secsize
)
2475 /* Skip non-zero chars */
2478 if ((*secsize
)-- <= 1)
2482 /* Skip any zero padding. */
2483 while (!string
[0]) {
2485 if ((*secsize
)-- <= 1)
2491 static char *get_next_modinfo(const struct load_info
*info
, const char *tag
,
2495 unsigned int taglen
= strlen(tag
);
2496 Elf_Shdr
*infosec
= &info
->sechdrs
[info
->index
.info
];
2497 unsigned long size
= infosec
->sh_size
;
2500 * get_modinfo() calls made before rewrite_section_headers()
2501 * must use sh_offset, as sh_addr isn't set!
2503 char *modinfo
= (char *)info
->hdr
+ infosec
->sh_offset
;
2506 size
-= prev
- modinfo
;
2507 modinfo
= next_string(prev
, &size
);
2510 for (p
= modinfo
; p
; p
= next_string(p
, &size
)) {
2511 if (strncmp(p
, tag
, taglen
) == 0 && p
[taglen
] == '=')
2512 return p
+ taglen
+ 1;
2517 static char *get_modinfo(const struct load_info
*info
, const char *tag
)
2519 return get_next_modinfo(info
, tag
, NULL
);
2522 static void setup_modinfo(struct module
*mod
, struct load_info
*info
)
2524 struct module_attribute
*attr
;
2527 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
2529 attr
->setup(mod
, get_modinfo(info
, attr
->attr
.name
));
2533 static void free_modinfo(struct module
*mod
)
2535 struct module_attribute
*attr
;
2538 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
2544 #ifdef CONFIG_KALLSYMS
2546 /* Lookup exported symbol in given range of kernel_symbols */
2547 static const struct kernel_symbol
*lookup_exported_symbol(const char *name
,
2548 const struct kernel_symbol
*start
,
2549 const struct kernel_symbol
*stop
)
2551 return bsearch(name
, start
, stop
- start
,
2552 sizeof(struct kernel_symbol
), cmp_name
);
2555 static int is_exported(const char *name
, unsigned long value
,
2556 const struct module
*mod
)
2558 const struct kernel_symbol
*ks
;
2560 ks
= lookup_exported_symbol(name
, __start___ksymtab
, __stop___ksymtab
);
2562 ks
= lookup_exported_symbol(name
, mod
->syms
, mod
->syms
+ mod
->num_syms
);
2564 return ks
!= NULL
&& kernel_symbol_value(ks
) == value
;
2568 static char elf_type(const Elf_Sym
*sym
, const struct load_info
*info
)
2570 const Elf_Shdr
*sechdrs
= info
->sechdrs
;
2572 if (ELF_ST_BIND(sym
->st_info
) == STB_WEAK
) {
2573 if (ELF_ST_TYPE(sym
->st_info
) == STT_OBJECT
)
2578 if (sym
->st_shndx
== SHN_UNDEF
)
2580 if (sym
->st_shndx
== SHN_ABS
|| sym
->st_shndx
== info
->index
.pcpu
)
2582 if (sym
->st_shndx
>= SHN_LORESERVE
)
2584 if (sechdrs
[sym
->st_shndx
].sh_flags
& SHF_EXECINSTR
)
2586 if (sechdrs
[sym
->st_shndx
].sh_flags
& SHF_ALLOC
2587 && sechdrs
[sym
->st_shndx
].sh_type
!= SHT_NOBITS
) {
2588 if (!(sechdrs
[sym
->st_shndx
].sh_flags
& SHF_WRITE
))
2590 else if (sechdrs
[sym
->st_shndx
].sh_flags
& ARCH_SHF_SMALL
)
2595 if (sechdrs
[sym
->st_shndx
].sh_type
== SHT_NOBITS
) {
2596 if (sechdrs
[sym
->st_shndx
].sh_flags
& ARCH_SHF_SMALL
)
2601 if (strstarts(info
->secstrings
+ sechdrs
[sym
->st_shndx
].sh_name
,
2608 static bool is_core_symbol(const Elf_Sym
*src
, const Elf_Shdr
*sechdrs
,
2609 unsigned int shnum
, unsigned int pcpundx
)
2611 const Elf_Shdr
*sec
;
2613 if (src
->st_shndx
== SHN_UNDEF
2614 || src
->st_shndx
>= shnum
2618 #ifdef CONFIG_KALLSYMS_ALL
2619 if (src
->st_shndx
== pcpundx
)
2623 sec
= sechdrs
+ src
->st_shndx
;
2624 if (!(sec
->sh_flags
& SHF_ALLOC
)
2625 #ifndef CONFIG_KALLSYMS_ALL
2626 || !(sec
->sh_flags
& SHF_EXECINSTR
)
2628 || (sec
->sh_entsize
& INIT_OFFSET_MASK
))
2635 * We only allocate and copy the strings needed by the parts of symtab
2636 * we keep. This is simple, but has the effect of making multiple
2637 * copies of duplicates. We could be more sophisticated, see
2638 * linux-kernel thread starting with
2639 * <73defb5e4bca04a6431392cc341112b1@localhost>.
2641 static void layout_symtab(struct module
*mod
, struct load_info
*info
)
2643 Elf_Shdr
*symsect
= info
->sechdrs
+ info
->index
.sym
;
2644 Elf_Shdr
*strsect
= info
->sechdrs
+ info
->index
.str
;
2646 unsigned int i
, nsrc
, ndst
, strtab_size
= 0;
2648 /* Put symbol section at end of init part of module. */
2649 symsect
->sh_flags
|= SHF_ALLOC
;
2650 symsect
->sh_entsize
= get_offset(mod
, &mod
->init_layout
.size
, symsect
,
2651 info
->index
.sym
) | INIT_OFFSET_MASK
;
2652 pr_debug("\t%s\n", info
->secstrings
+ symsect
->sh_name
);
2654 src
= (void *)info
->hdr
+ symsect
->sh_offset
;
2655 nsrc
= symsect
->sh_size
/ sizeof(*src
);
2657 /* Compute total space required for the core symbols' strtab. */
2658 for (ndst
= i
= 0; i
< nsrc
; i
++) {
2659 if (i
== 0 || is_livepatch_module(mod
) ||
2660 is_core_symbol(src
+i
, info
->sechdrs
, info
->hdr
->e_shnum
,
2661 info
->index
.pcpu
)) {
2662 strtab_size
+= strlen(&info
->strtab
[src
[i
].st_name
])+1;
2667 /* Append room for core symbols at end of core part. */
2668 info
->symoffs
= ALIGN(mod
->core_layout
.size
, symsect
->sh_addralign
?: 1);
2669 info
->stroffs
= mod
->core_layout
.size
= info
->symoffs
+ ndst
* sizeof(Elf_Sym
);
2670 mod
->core_layout
.size
+= strtab_size
;
2671 info
->core_typeoffs
= mod
->core_layout
.size
;
2672 mod
->core_layout
.size
+= ndst
* sizeof(char);
2673 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2675 /* Put string table section at end of init part of module. */
2676 strsect
->sh_flags
|= SHF_ALLOC
;
2677 strsect
->sh_entsize
= get_offset(mod
, &mod
->init_layout
.size
, strsect
,
2678 info
->index
.str
) | INIT_OFFSET_MASK
;
2679 pr_debug("\t%s\n", info
->secstrings
+ strsect
->sh_name
);
2681 /* We'll tack temporary mod_kallsyms on the end. */
2682 mod
->init_layout
.size
= ALIGN(mod
->init_layout
.size
,
2683 __alignof__(struct mod_kallsyms
));
2684 info
->mod_kallsyms_init_off
= mod
->init_layout
.size
;
2685 mod
->init_layout
.size
+= sizeof(struct mod_kallsyms
);
2686 info
->init_typeoffs
= mod
->init_layout
.size
;
2687 mod
->init_layout
.size
+= nsrc
* sizeof(char);
2688 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2692 * We use the full symtab and strtab which layout_symtab arranged to
2693 * be appended to the init section. Later we switch to the cut-down
2696 static void add_kallsyms(struct module
*mod
, const struct load_info
*info
)
2698 unsigned int i
, ndst
;
2702 Elf_Shdr
*symsec
= &info
->sechdrs
[info
->index
.sym
];
2704 /* Set up to point into init section. */
2705 mod
->kallsyms
= mod
->init_layout
.base
+ info
->mod_kallsyms_init_off
;
2707 mod
->kallsyms
->symtab
= (void *)symsec
->sh_addr
;
2708 mod
->kallsyms
->num_symtab
= symsec
->sh_size
/ sizeof(Elf_Sym
);
2709 /* Make sure we get permanent strtab: don't use info->strtab. */
2710 mod
->kallsyms
->strtab
= (void *)info
->sechdrs
[info
->index
.str
].sh_addr
;
2711 mod
->kallsyms
->typetab
= mod
->init_layout
.base
+ info
->init_typeoffs
;
2714 * Now populate the cut down core kallsyms for after init
2715 * and set types up while we still have access to sections.
2717 mod
->core_kallsyms
.symtab
= dst
= mod
->core_layout
.base
+ info
->symoffs
;
2718 mod
->core_kallsyms
.strtab
= s
= mod
->core_layout
.base
+ info
->stroffs
;
2719 mod
->core_kallsyms
.typetab
= mod
->core_layout
.base
+ info
->core_typeoffs
;
2720 src
= mod
->kallsyms
->symtab
;
2721 for (ndst
= i
= 0; i
< mod
->kallsyms
->num_symtab
; i
++) {
2722 mod
->kallsyms
->typetab
[i
] = elf_type(src
+ i
, info
);
2723 if (i
== 0 || is_livepatch_module(mod
) ||
2724 is_core_symbol(src
+i
, info
->sechdrs
, info
->hdr
->e_shnum
,
2725 info
->index
.pcpu
)) {
2726 mod
->core_kallsyms
.typetab
[ndst
] =
2727 mod
->kallsyms
->typetab
[i
];
2729 dst
[ndst
++].st_name
= s
- mod
->core_kallsyms
.strtab
;
2730 s
+= strlcpy(s
, &mod
->kallsyms
->strtab
[src
[i
].st_name
],
2734 mod
->core_kallsyms
.num_symtab
= ndst
;
2737 static inline void layout_symtab(struct module
*mod
, struct load_info
*info
)
2741 static void add_kallsyms(struct module
*mod
, const struct load_info
*info
)
2744 #endif /* CONFIG_KALLSYMS */
2746 static void dynamic_debug_setup(struct module
*mod
, struct _ddebug
*debug
, unsigned int num
)
2750 ddebug_add_module(debug
, num
, mod
->name
);
2753 static void dynamic_debug_remove(struct module
*mod
, struct _ddebug
*debug
)
2756 ddebug_remove_module(mod
->name
);
2759 void * __weak
module_alloc(unsigned long size
)
2761 return vmalloc_exec(size
);
2764 bool __weak
module_init_section(const char *name
)
2766 return strstarts(name
, ".init");
2769 bool __weak
module_exit_section(const char *name
)
2771 return strstarts(name
, ".exit");
2774 #ifdef CONFIG_DEBUG_KMEMLEAK
2775 static void kmemleak_load_module(const struct module
*mod
,
2776 const struct load_info
*info
)
2780 /* only scan the sections containing data */
2781 kmemleak_scan_area(mod
, sizeof(struct module
), GFP_KERNEL
);
2783 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2784 /* Scan all writable sections that's not executable */
2785 if (!(info
->sechdrs
[i
].sh_flags
& SHF_ALLOC
) ||
2786 !(info
->sechdrs
[i
].sh_flags
& SHF_WRITE
) ||
2787 (info
->sechdrs
[i
].sh_flags
& SHF_EXECINSTR
))
2790 kmemleak_scan_area((void *)info
->sechdrs
[i
].sh_addr
,
2791 info
->sechdrs
[i
].sh_size
, GFP_KERNEL
);
2795 static inline void kmemleak_load_module(const struct module
*mod
,
2796 const struct load_info
*info
)
2801 #ifdef CONFIG_MODULE_SIG
2802 static int module_sig_check(struct load_info
*info
, int flags
)
2805 const unsigned long markerlen
= sizeof(MODULE_SIG_STRING
) - 1;
2807 const void *mod
= info
->hdr
;
2810 * Require flags == 0, as a module with version information
2811 * removed is no longer the module that was signed
2814 info
->len
> markerlen
&&
2815 memcmp(mod
+ info
->len
- markerlen
, MODULE_SIG_STRING
, markerlen
) == 0) {
2816 /* We truncate the module to discard the signature */
2817 info
->len
-= markerlen
;
2818 err
= mod_verify_sig(mod
, info
);
2823 info
->sig_ok
= true;
2826 /* We don't permit modules to be loaded into trusted kernels
2827 * without a valid signature on them, but if we're not
2828 * enforcing, certain errors are non-fatal.
2831 reason
= "Loading of unsigned module";
2834 reason
= "Loading of module with unsupported crypto";
2837 reason
= "Loading of module with unavailable key";
2839 if (is_module_sig_enforced()) {
2840 pr_notice("%s: %s is rejected\n", info
->name
, reason
);
2841 return -EKEYREJECTED
;
2844 return security_locked_down(LOCKDOWN_MODULE_SIGNATURE
);
2846 /* All other errors are fatal, including nomem, unparseable
2847 * signatures and signature check failures - even if signatures
2854 #else /* !CONFIG_MODULE_SIG */
2855 static int module_sig_check(struct load_info
*info
, int flags
)
2859 #endif /* !CONFIG_MODULE_SIG */
2861 /* Sanity checks against invalid binaries, wrong arch, weird elf version. */
2862 static int elf_header_check(struct load_info
*info
)
2864 if (info
->len
< sizeof(*(info
->hdr
)))
2867 if (memcmp(info
->hdr
->e_ident
, ELFMAG
, SELFMAG
) != 0
2868 || info
->hdr
->e_type
!= ET_REL
2869 || !elf_check_arch(info
->hdr
)
2870 || info
->hdr
->e_shentsize
!= sizeof(Elf_Shdr
))
2873 if (info
->hdr
->e_shoff
>= info
->len
2874 || (info
->hdr
->e_shnum
* sizeof(Elf_Shdr
) >
2875 info
->len
- info
->hdr
->e_shoff
))
2881 #define COPY_CHUNK_SIZE (16*PAGE_SIZE)
2883 static int copy_chunked_from_user(void *dst
, const void __user
*usrc
, unsigned long len
)
2886 unsigned long n
= min(len
, COPY_CHUNK_SIZE
);
2888 if (copy_from_user(dst
, usrc
, n
) != 0)
2898 #ifdef CONFIG_LIVEPATCH
2899 static int check_modinfo_livepatch(struct module
*mod
, struct load_info
*info
)
2901 if (get_modinfo(info
, "livepatch")) {
2903 add_taint_module(mod
, TAINT_LIVEPATCH
, LOCKDEP_STILL_OK
);
2904 pr_notice_once("%s: tainting kernel with TAINT_LIVEPATCH\n",
2910 #else /* !CONFIG_LIVEPATCH */
2911 static int check_modinfo_livepatch(struct module
*mod
, struct load_info
*info
)
2913 if (get_modinfo(info
, "livepatch")) {
2914 pr_err("%s: module is marked as livepatch module, but livepatch support is disabled",
2921 #endif /* CONFIG_LIVEPATCH */
2923 static void check_modinfo_retpoline(struct module
*mod
, struct load_info
*info
)
2925 if (retpoline_module_ok(get_modinfo(info
, "retpoline")))
2928 pr_warn("%s: loading module not compiled with retpoline compiler.\n",
2932 /* Sets info->hdr and info->len. */
2933 static int copy_module_from_user(const void __user
*umod
, unsigned long len
,
2934 struct load_info
*info
)
2939 if (info
->len
< sizeof(*(info
->hdr
)))
2942 err
= security_kernel_load_data(LOADING_MODULE
);
2946 /* Suck in entire file: we'll want most of it. */
2947 info
->hdr
= __vmalloc(info
->len
, GFP_KERNEL
| __GFP_NOWARN
);
2951 if (copy_chunked_from_user(info
->hdr
, umod
, info
->len
) != 0) {
2959 static void free_copy(struct load_info
*info
)
2964 static int rewrite_section_headers(struct load_info
*info
, int flags
)
2968 /* This should always be true, but let's be sure. */
2969 info
->sechdrs
[0].sh_addr
= 0;
2971 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2972 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
2973 if (shdr
->sh_type
!= SHT_NOBITS
2974 && info
->len
< shdr
->sh_offset
+ shdr
->sh_size
) {
2975 pr_err("Module len %lu truncated\n", info
->len
);
2979 /* Mark all sections sh_addr with their address in the
2981 shdr
->sh_addr
= (size_t)info
->hdr
+ shdr
->sh_offset
;
2983 #ifndef CONFIG_MODULE_UNLOAD
2984 /* Don't load .exit sections */
2985 if (module_exit_section(info
->secstrings
+shdr
->sh_name
))
2986 shdr
->sh_flags
&= ~(unsigned long)SHF_ALLOC
;
2990 /* Track but don't keep modinfo and version sections. */
2991 info
->sechdrs
[info
->index
.vers
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
2992 info
->sechdrs
[info
->index
.info
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
2998 * Set up our basic convenience variables (pointers to section headers,
2999 * search for module section index etc), and do some basic section
3002 * Set info->mod to the temporary copy of the module in info->hdr. The final one
3003 * will be allocated in move_module().
3005 static int setup_load_info(struct load_info
*info
, int flags
)
3009 /* Set up the convenience variables */
3010 info
->sechdrs
= (void *)info
->hdr
+ info
->hdr
->e_shoff
;
3011 info
->secstrings
= (void *)info
->hdr
3012 + info
->sechdrs
[info
->hdr
->e_shstrndx
].sh_offset
;
3014 /* Try to find a name early so we can log errors with a module name */
3015 info
->index
.info
= find_sec(info
, ".modinfo");
3016 if (info
->index
.info
)
3017 info
->name
= get_modinfo(info
, "name");
3019 /* Find internal symbols and strings. */
3020 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
3021 if (info
->sechdrs
[i
].sh_type
== SHT_SYMTAB
) {
3022 info
->index
.sym
= i
;
3023 info
->index
.str
= info
->sechdrs
[i
].sh_link
;
3024 info
->strtab
= (char *)info
->hdr
3025 + info
->sechdrs
[info
->index
.str
].sh_offset
;
3030 if (info
->index
.sym
== 0) {
3031 pr_warn("%s: module has no symbols (stripped?)\n",
3032 info
->name
?: "(missing .modinfo section or name field)");
3036 info
->index
.mod
= find_sec(info
, ".gnu.linkonce.this_module");
3037 if (!info
->index
.mod
) {
3038 pr_warn("%s: No module found in object\n",
3039 info
->name
?: "(missing .modinfo section or name field)");
3042 /* This is temporary: point mod into copy of data. */
3043 info
->mod
= (void *)info
->hdr
+ info
->sechdrs
[info
->index
.mod
].sh_offset
;
3046 * If we didn't load the .modinfo 'name' field earlier, fall back to
3047 * on-disk struct mod 'name' field.
3050 info
->name
= info
->mod
->name
;
3052 if (flags
& MODULE_INIT_IGNORE_MODVERSIONS
)
3053 info
->index
.vers
= 0; /* Pretend no __versions section! */
3055 info
->index
.vers
= find_sec(info
, "__versions");
3057 info
->index
.pcpu
= find_pcpusec(info
);
3062 static int check_modinfo(struct module
*mod
, struct load_info
*info
, int flags
)
3064 const char *modmagic
= get_modinfo(info
, "vermagic");
3067 if (flags
& MODULE_INIT_IGNORE_VERMAGIC
)
3070 /* This is allowed: modprobe --force will invalidate it. */
3072 err
= try_to_force_load(mod
, "bad vermagic");
3075 } else if (!same_magic(modmagic
, vermagic
, info
->index
.vers
)) {
3076 pr_err("%s: version magic '%s' should be '%s'\n",
3077 info
->name
, modmagic
, vermagic
);
3081 if (!get_modinfo(info
, "intree")) {
3082 if (!test_taint(TAINT_OOT_MODULE
))
3083 pr_warn("%s: loading out-of-tree module taints kernel.\n",
3085 add_taint_module(mod
, TAINT_OOT_MODULE
, LOCKDEP_STILL_OK
);
3088 check_modinfo_retpoline(mod
, info
);
3090 if (get_modinfo(info
, "staging")) {
3091 add_taint_module(mod
, TAINT_CRAP
, LOCKDEP_STILL_OK
);
3092 pr_warn("%s: module is from the staging directory, the quality "
3093 "is unknown, you have been warned.\n", mod
->name
);
3096 err
= check_modinfo_livepatch(mod
, info
);
3100 /* Set up license info based on the info section */
3101 set_license(mod
, get_modinfo(info
, "license"));
3106 static int find_module_sections(struct module
*mod
, struct load_info
*info
)
3108 mod
->kp
= section_objs(info
, "__param",
3109 sizeof(*mod
->kp
), &mod
->num_kp
);
3110 mod
->syms
= section_objs(info
, "__ksymtab",
3111 sizeof(*mod
->syms
), &mod
->num_syms
);
3112 mod
->crcs
= section_addr(info
, "__kcrctab");
3113 mod
->gpl_syms
= section_objs(info
, "__ksymtab_gpl",
3114 sizeof(*mod
->gpl_syms
),
3115 &mod
->num_gpl_syms
);
3116 mod
->gpl_crcs
= section_addr(info
, "__kcrctab_gpl");
3117 mod
->gpl_future_syms
= section_objs(info
,
3118 "__ksymtab_gpl_future",
3119 sizeof(*mod
->gpl_future_syms
),
3120 &mod
->num_gpl_future_syms
);
3121 mod
->gpl_future_crcs
= section_addr(info
, "__kcrctab_gpl_future");
3123 #ifdef CONFIG_UNUSED_SYMBOLS
3124 mod
->unused_syms
= section_objs(info
, "__ksymtab_unused",
3125 sizeof(*mod
->unused_syms
),
3126 &mod
->num_unused_syms
);
3127 mod
->unused_crcs
= section_addr(info
, "__kcrctab_unused");
3128 mod
->unused_gpl_syms
= section_objs(info
, "__ksymtab_unused_gpl",
3129 sizeof(*mod
->unused_gpl_syms
),
3130 &mod
->num_unused_gpl_syms
);
3131 mod
->unused_gpl_crcs
= section_addr(info
, "__kcrctab_unused_gpl");
3133 #ifdef CONFIG_CONSTRUCTORS
3134 mod
->ctors
= section_objs(info
, ".ctors",
3135 sizeof(*mod
->ctors
), &mod
->num_ctors
);
3137 mod
->ctors
= section_objs(info
, ".init_array",
3138 sizeof(*mod
->ctors
), &mod
->num_ctors
);
3139 else if (find_sec(info
, ".init_array")) {
3141 * This shouldn't happen with same compiler and binutils
3142 * building all parts of the module.
3144 pr_warn("%s: has both .ctors and .init_array.\n",
3150 mod
->noinstr_text_start
= section_objs(info
, ".noinstr.text", 1,
3151 &mod
->noinstr_text_size
);
3153 #ifdef CONFIG_TRACEPOINTS
3154 mod
->tracepoints_ptrs
= section_objs(info
, "__tracepoints_ptrs",
3155 sizeof(*mod
->tracepoints_ptrs
),
3156 &mod
->num_tracepoints
);
3158 #ifdef CONFIG_TREE_SRCU
3159 mod
->srcu_struct_ptrs
= section_objs(info
, "___srcu_struct_ptrs",
3160 sizeof(*mod
->srcu_struct_ptrs
),
3161 &mod
->num_srcu_structs
);
3163 #ifdef CONFIG_BPF_EVENTS
3164 mod
->bpf_raw_events
= section_objs(info
, "__bpf_raw_tp_map",
3165 sizeof(*mod
->bpf_raw_events
),
3166 &mod
->num_bpf_raw_events
);
3168 #ifdef CONFIG_JUMP_LABEL
3169 mod
->jump_entries
= section_objs(info
, "__jump_table",
3170 sizeof(*mod
->jump_entries
),
3171 &mod
->num_jump_entries
);
3173 #ifdef CONFIG_EVENT_TRACING
3174 mod
->trace_events
= section_objs(info
, "_ftrace_events",
3175 sizeof(*mod
->trace_events
),
3176 &mod
->num_trace_events
);
3177 mod
->trace_evals
= section_objs(info
, "_ftrace_eval_map",
3178 sizeof(*mod
->trace_evals
),
3179 &mod
->num_trace_evals
);
3181 #ifdef CONFIG_TRACING
3182 mod
->trace_bprintk_fmt_start
= section_objs(info
, "__trace_printk_fmt",
3183 sizeof(*mod
->trace_bprintk_fmt_start
),
3184 &mod
->num_trace_bprintk_fmt
);
3186 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
3187 /* sechdrs[0].sh_size is always zero */
3188 mod
->ftrace_callsites
= section_objs(info
, FTRACE_CALLSITE_SECTION
,
3189 sizeof(*mod
->ftrace_callsites
),
3190 &mod
->num_ftrace_callsites
);
3192 #ifdef CONFIG_FUNCTION_ERROR_INJECTION
3193 mod
->ei_funcs
= section_objs(info
, "_error_injection_whitelist",
3194 sizeof(*mod
->ei_funcs
),
3195 &mod
->num_ei_funcs
);
3197 #ifdef CONFIG_KPROBES
3198 mod
->kprobes_text_start
= section_objs(info
, ".kprobes.text", 1,
3199 &mod
->kprobes_text_size
);
3200 mod
->kprobe_blacklist
= section_objs(info
, "_kprobe_blacklist",
3201 sizeof(unsigned long),
3202 &mod
->num_kprobe_blacklist
);
3204 mod
->extable
= section_objs(info
, "__ex_table",
3205 sizeof(*mod
->extable
), &mod
->num_exentries
);
3207 if (section_addr(info
, "__obsparm"))
3208 pr_warn("%s: Ignoring obsolete parameters\n", mod
->name
);
3210 info
->debug
= section_objs(info
, "__verbose",
3211 sizeof(*info
->debug
), &info
->num_debug
);
3216 static int move_module(struct module
*mod
, struct load_info
*info
)
3221 /* Do the allocs. */
3222 ptr
= module_alloc(mod
->core_layout
.size
);
3224 * The pointer to this block is stored in the module structure
3225 * which is inside the block. Just mark it as not being a
3228 kmemleak_not_leak(ptr
);
3232 memset(ptr
, 0, mod
->core_layout
.size
);
3233 mod
->core_layout
.base
= ptr
;
3235 if (mod
->init_layout
.size
) {
3236 ptr
= module_alloc(mod
->init_layout
.size
);
3238 * The pointer to this block is stored in the module structure
3239 * which is inside the block. This block doesn't need to be
3240 * scanned as it contains data and code that will be freed
3241 * after the module is initialized.
3243 kmemleak_ignore(ptr
);
3245 module_memfree(mod
->core_layout
.base
);
3248 memset(ptr
, 0, mod
->init_layout
.size
);
3249 mod
->init_layout
.base
= ptr
;
3251 mod
->init_layout
.base
= NULL
;
3253 /* Transfer each section which specifies SHF_ALLOC */
3254 pr_debug("final section addresses:\n");
3255 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++) {
3257 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
3259 if (!(shdr
->sh_flags
& SHF_ALLOC
))
3262 if (shdr
->sh_entsize
& INIT_OFFSET_MASK
)
3263 dest
= mod
->init_layout
.base
3264 + (shdr
->sh_entsize
& ~INIT_OFFSET_MASK
);
3266 dest
= mod
->core_layout
.base
+ shdr
->sh_entsize
;
3268 if (shdr
->sh_type
!= SHT_NOBITS
)
3269 memcpy(dest
, (void *)shdr
->sh_addr
, shdr
->sh_size
);
3270 /* Update sh_addr to point to copy in image. */
3271 shdr
->sh_addr
= (unsigned long)dest
;
3272 pr_debug("\t0x%lx %s\n",
3273 (long)shdr
->sh_addr
, info
->secstrings
+ shdr
->sh_name
);
3279 static int check_module_license_and_versions(struct module
*mod
)
3281 int prev_taint
= test_taint(TAINT_PROPRIETARY_MODULE
);
3284 * ndiswrapper is under GPL by itself, but loads proprietary modules.
3285 * Don't use add_taint_module(), as it would prevent ndiswrapper from
3286 * using GPL-only symbols it needs.
3288 if (strcmp(mod
->name
, "ndiswrapper") == 0)
3289 add_taint(TAINT_PROPRIETARY_MODULE
, LOCKDEP_NOW_UNRELIABLE
);
3291 /* driverloader was caught wrongly pretending to be under GPL */
3292 if (strcmp(mod
->name
, "driverloader") == 0)
3293 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
3294 LOCKDEP_NOW_UNRELIABLE
);
3296 /* lve claims to be GPL but upstream won't provide source */
3297 if (strcmp(mod
->name
, "lve") == 0)
3298 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
3299 LOCKDEP_NOW_UNRELIABLE
);
3301 if (!prev_taint
&& test_taint(TAINT_PROPRIETARY_MODULE
))
3302 pr_warn("%s: module license taints kernel.\n", mod
->name
);
3304 #ifdef CONFIG_MODVERSIONS
3305 if ((mod
->num_syms
&& !mod
->crcs
)
3306 || (mod
->num_gpl_syms
&& !mod
->gpl_crcs
)
3307 || (mod
->num_gpl_future_syms
&& !mod
->gpl_future_crcs
)
3308 #ifdef CONFIG_UNUSED_SYMBOLS
3309 || (mod
->num_unused_syms
&& !mod
->unused_crcs
)
3310 || (mod
->num_unused_gpl_syms
&& !mod
->unused_gpl_crcs
)
3313 return try_to_force_load(mod
,
3314 "no versions for exported symbols");
3320 static void flush_module_icache(const struct module
*mod
)
3322 mm_segment_t old_fs
;
3324 /* flush the icache in correct context */
3329 * Flush the instruction cache, since we've played with text.
3330 * Do it before processing of module parameters, so the module
3331 * can provide parameter accessor functions of its own.
3333 if (mod
->init_layout
.base
)
3334 flush_icache_range((unsigned long)mod
->init_layout
.base
,
3335 (unsigned long)mod
->init_layout
.base
3336 + mod
->init_layout
.size
);
3337 flush_icache_range((unsigned long)mod
->core_layout
.base
,
3338 (unsigned long)mod
->core_layout
.base
+ mod
->core_layout
.size
);
3343 int __weak
module_frob_arch_sections(Elf_Ehdr
*hdr
,
3351 /* module_blacklist is a comma-separated list of module names */
3352 static char *module_blacklist
;
3353 static bool blacklisted(const char *module_name
)
3358 if (!module_blacklist
)
3361 for (p
= module_blacklist
; *p
; p
+= len
) {
3362 len
= strcspn(p
, ",");
3363 if (strlen(module_name
) == len
&& !memcmp(module_name
, p
, len
))
3370 core_param(module_blacklist
, module_blacklist
, charp
, 0400);
3372 static struct module
*layout_and_allocate(struct load_info
*info
, int flags
)
3378 err
= check_modinfo(info
->mod
, info
, flags
);
3380 return ERR_PTR(err
);
3382 /* Allow arches to frob section contents and sizes. */
3383 err
= module_frob_arch_sections(info
->hdr
, info
->sechdrs
,
3384 info
->secstrings
, info
->mod
);
3386 return ERR_PTR(err
);
3388 /* We will do a special allocation for per-cpu sections later. */
3389 info
->sechdrs
[info
->index
.pcpu
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
3392 * Mark ro_after_init section with SHF_RO_AFTER_INIT so that
3393 * layout_sections() can put it in the right place.
3394 * Note: ro_after_init sections also have SHF_{WRITE,ALLOC} set.
3396 ndx
= find_sec(info
, ".data..ro_after_init");
3398 info
->sechdrs
[ndx
].sh_flags
|= SHF_RO_AFTER_INIT
;
3400 * Mark the __jump_table section as ro_after_init as well: these data
3401 * structures are never modified, with the exception of entries that
3402 * refer to code in the __init section, which are annotated as such
3403 * at module load time.
3405 ndx
= find_sec(info
, "__jump_table");
3407 info
->sechdrs
[ndx
].sh_flags
|= SHF_RO_AFTER_INIT
;
3409 /* Determine total sizes, and put offsets in sh_entsize. For now
3410 this is done generically; there doesn't appear to be any
3411 special cases for the architectures. */
3412 layout_sections(info
->mod
, info
);
3413 layout_symtab(info
->mod
, info
);
3415 /* Allocate and move to the final place */
3416 err
= move_module(info
->mod
, info
);
3418 return ERR_PTR(err
);
3420 /* Module has been copied to its final place now: return it. */
3421 mod
= (void *)info
->sechdrs
[info
->index
.mod
].sh_addr
;
3422 kmemleak_load_module(mod
, info
);
3426 /* mod is no longer valid after this! */
3427 static void module_deallocate(struct module
*mod
, struct load_info
*info
)
3429 percpu_modfree(mod
);
3430 module_arch_freeing_init(mod
);
3431 module_memfree(mod
->init_layout
.base
);
3432 module_memfree(mod
->core_layout
.base
);
3435 int __weak
module_finalize(const Elf_Ehdr
*hdr
,
3436 const Elf_Shdr
*sechdrs
,
3442 static int post_relocation(struct module
*mod
, const struct load_info
*info
)
3444 /* Sort exception table now relocations are done. */
3445 sort_extable(mod
->extable
, mod
->extable
+ mod
->num_exentries
);
3447 /* Copy relocated percpu area over. */
3448 percpu_modcopy(mod
, (void *)info
->sechdrs
[info
->index
.pcpu
].sh_addr
,
3449 info
->sechdrs
[info
->index
.pcpu
].sh_size
);
3451 /* Setup kallsyms-specific fields. */
3452 add_kallsyms(mod
, info
);
3454 /* Arch-specific module finalizing. */
3455 return module_finalize(info
->hdr
, info
->sechdrs
, mod
);
3458 /* Is this module of this name done loading? No locks held. */
3459 static bool finished_loading(const char *name
)
3465 * The module_mutex should not be a heavily contended lock;
3466 * if we get the occasional sleep here, we'll go an extra iteration
3467 * in the wait_event_interruptible(), which is harmless.
3469 sched_annotate_sleep();
3470 mutex_lock(&module_mutex
);
3471 mod
= find_module_all(name
, strlen(name
), true);
3472 ret
= !mod
|| mod
->state
== MODULE_STATE_LIVE
;
3473 mutex_unlock(&module_mutex
);
3478 /* Call module constructors. */
3479 static void do_mod_ctors(struct module
*mod
)
3481 #ifdef CONFIG_CONSTRUCTORS
3484 for (i
= 0; i
< mod
->num_ctors
; i
++)
3489 /* For freeing module_init on success, in case kallsyms traversing */
3490 struct mod_initfree
{
3491 struct llist_node node
;
3495 static void do_free_init(struct work_struct
*w
)
3497 struct llist_node
*pos
, *n
, *list
;
3498 struct mod_initfree
*initfree
;
3500 list
= llist_del_all(&init_free_list
);
3504 llist_for_each_safe(pos
, n
, list
) {
3505 initfree
= container_of(pos
, struct mod_initfree
, node
);
3506 module_memfree(initfree
->module_init
);
3511 static int __init
modules_wq_init(void)
3513 INIT_WORK(&init_free_wq
, do_free_init
);
3514 init_llist_head(&init_free_list
);
3517 module_init(modules_wq_init
);
3520 * This is where the real work happens.
3522 * Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb
3523 * helper command 'lx-symbols'.
3525 static noinline
int do_init_module(struct module
*mod
)
3528 struct mod_initfree
*freeinit
;
3530 freeinit
= kmalloc(sizeof(*freeinit
), GFP_KERNEL
);
3535 freeinit
->module_init
= mod
->init_layout
.base
;
3538 * We want to find out whether @mod uses async during init. Clear
3539 * PF_USED_ASYNC. async_schedule*() will set it.
3541 current
->flags
&= ~PF_USED_ASYNC
;
3544 /* Start the module */
3545 if (mod
->init
!= NULL
)
3546 ret
= do_one_initcall(mod
->init
);
3548 goto fail_free_freeinit
;
3551 pr_warn("%s: '%s'->init suspiciously returned %d, it should "
3552 "follow 0/-E convention\n"
3553 "%s: loading module anyway...\n",
3554 __func__
, mod
->name
, ret
, __func__
);
3558 /* Now it's a first class citizen! */
3559 mod
->state
= MODULE_STATE_LIVE
;
3560 blocking_notifier_call_chain(&module_notify_list
,
3561 MODULE_STATE_LIVE
, mod
);
3564 * We need to finish all async code before the module init sequence
3565 * is done. This has potential to deadlock. For example, a newly
3566 * detected block device can trigger request_module() of the
3567 * default iosched from async probing task. Once userland helper
3568 * reaches here, async_synchronize_full() will wait on the async
3569 * task waiting on request_module() and deadlock.
3571 * This deadlock is avoided by perfomring async_synchronize_full()
3572 * iff module init queued any async jobs. This isn't a full
3573 * solution as it will deadlock the same if module loading from
3574 * async jobs nests more than once; however, due to the various
3575 * constraints, this hack seems to be the best option for now.
3576 * Please refer to the following thread for details.
3578 * http://thread.gmane.org/gmane.linux.kernel/1420814
3580 if (!mod
->async_probe_requested
&& (current
->flags
& PF_USED_ASYNC
))
3581 async_synchronize_full();
3583 ftrace_free_mem(mod
, mod
->init_layout
.base
, mod
->init_layout
.base
+
3584 mod
->init_layout
.size
);
3585 mutex_lock(&module_mutex
);
3586 /* Drop initial reference. */
3588 trim_init_extable(mod
);
3589 #ifdef CONFIG_KALLSYMS
3590 /* Switch to core kallsyms now init is done: kallsyms may be walking! */
3591 rcu_assign_pointer(mod
->kallsyms
, &mod
->core_kallsyms
);
3593 module_enable_ro(mod
, true);
3594 mod_tree_remove_init(mod
);
3595 module_arch_freeing_init(mod
);
3596 mod
->init_layout
.base
= NULL
;
3597 mod
->init_layout
.size
= 0;
3598 mod
->init_layout
.ro_size
= 0;
3599 mod
->init_layout
.ro_after_init_size
= 0;
3600 mod
->init_layout
.text_size
= 0;
3602 * We want to free module_init, but be aware that kallsyms may be
3603 * walking this with preempt disabled. In all the failure paths, we
3604 * call synchronize_rcu(), but we don't want to slow down the success
3605 * path. module_memfree() cannot be called in an interrupt, so do the
3606 * work and call synchronize_rcu() in a work queue.
3608 * Note that module_alloc() on most architectures creates W+X page
3609 * mappings which won't be cleaned up until do_free_init() runs. Any
3610 * code such as mark_rodata_ro() which depends on those mappings to
3611 * be cleaned up needs to sync with the queued work - ie
3614 if (llist_add(&freeinit
->node
, &init_free_list
))
3615 schedule_work(&init_free_wq
);
3617 mutex_unlock(&module_mutex
);
3618 wake_up_all(&module_wq
);
3625 /* Try to protect us from buggy refcounters. */
3626 mod
->state
= MODULE_STATE_GOING
;
3629 blocking_notifier_call_chain(&module_notify_list
,
3630 MODULE_STATE_GOING
, mod
);
3631 klp_module_going(mod
);
3632 ftrace_release_mod(mod
);
3634 wake_up_all(&module_wq
);
3638 static int may_init_module(void)
3640 if (!capable(CAP_SYS_MODULE
) || modules_disabled
)
3647 * We try to place it in the list now to make sure it's unique before
3648 * we dedicate too many resources. In particular, temporary percpu
3649 * memory exhaustion.
3651 static int add_unformed_module(struct module
*mod
)
3656 mod
->state
= MODULE_STATE_UNFORMED
;
3659 mutex_lock(&module_mutex
);
3660 old
= find_module_all(mod
->name
, strlen(mod
->name
), true);
3662 if (old
->state
!= MODULE_STATE_LIVE
) {
3663 /* Wait in case it fails to load. */
3664 mutex_unlock(&module_mutex
);
3665 err
= wait_event_interruptible(module_wq
,
3666 finished_loading(mod
->name
));
3674 mod_update_bounds(mod
);
3675 list_add_rcu(&mod
->list
, &modules
);
3676 mod_tree_insert(mod
);
3680 mutex_unlock(&module_mutex
);
3685 static int complete_formation(struct module
*mod
, struct load_info
*info
)
3689 mutex_lock(&module_mutex
);
3691 /* Find duplicate symbols (must be called under lock). */
3692 err
= verify_exported_symbols(mod
);
3696 /* This relies on module_mutex for list integrity. */
3697 module_bug_finalize(info
->hdr
, info
->sechdrs
, mod
);
3699 module_enable_ro(mod
, false);
3700 module_enable_nx(mod
);
3701 module_enable_x(mod
);
3703 /* Mark state as coming so strong_try_module_get() ignores us,
3704 * but kallsyms etc. can see us. */
3705 mod
->state
= MODULE_STATE_COMING
;
3706 mutex_unlock(&module_mutex
);
3711 mutex_unlock(&module_mutex
);
3715 static int prepare_coming_module(struct module
*mod
)
3719 ftrace_module_enable(mod
);
3720 err
= klp_module_coming(mod
);
3724 blocking_notifier_call_chain(&module_notify_list
,
3725 MODULE_STATE_COMING
, mod
);
3729 static int unknown_module_param_cb(char *param
, char *val
, const char *modname
,
3732 struct module
*mod
= arg
;
3735 if (strcmp(param
, "async_probe") == 0) {
3736 mod
->async_probe_requested
= true;
3740 /* Check for magic 'dyndbg' arg */
3741 ret
= ddebug_dyndbg_module_param_cb(param
, val
, modname
);
3743 pr_warn("%s: unknown parameter '%s' ignored\n", modname
, param
);
3747 /* Allocate and load the module: note that size of section 0 is always
3748 zero, and we rely on this for optional sections. */
3749 static int load_module(struct load_info
*info
, const char __user
*uargs
,
3756 err
= elf_header_check(info
);
3760 err
= setup_load_info(info
, flags
);
3764 if (blacklisted(info
->name
)) {
3769 err
= module_sig_check(info
, flags
);
3773 err
= rewrite_section_headers(info
, flags
);
3777 /* Check module struct version now, before we try to use module. */
3778 if (!check_modstruct_version(info
, info
->mod
)) {
3783 /* Figure out module layout, and allocate all the memory. */
3784 mod
= layout_and_allocate(info
, flags
);
3790 audit_log_kern_module(mod
->name
);
3792 /* Reserve our place in the list. */
3793 err
= add_unformed_module(mod
);
3797 #ifdef CONFIG_MODULE_SIG
3798 mod
->sig_ok
= info
->sig_ok
;
3800 pr_notice_once("%s: module verification failed: signature "
3801 "and/or required key missing - tainting "
3802 "kernel\n", mod
->name
);
3803 add_taint_module(mod
, TAINT_UNSIGNED_MODULE
, LOCKDEP_STILL_OK
);
3807 /* To avoid stressing percpu allocator, do this once we're unique. */
3808 err
= percpu_modalloc(mod
, info
);
3812 /* Now module is in final location, initialize linked lists, etc. */
3813 err
= module_unload_init(mod
);
3817 init_param_lock(mod
);
3819 /* Now we've got everything in the final locations, we can
3820 * find optional sections. */
3821 err
= find_module_sections(mod
, info
);
3825 err
= check_module_license_and_versions(mod
);
3829 /* Set up MODINFO_ATTR fields */
3830 setup_modinfo(mod
, info
);
3832 /* Fix up syms, so that st_value is a pointer to location. */
3833 err
= simplify_symbols(mod
, info
);
3837 err
= apply_relocations(mod
, info
);
3841 err
= post_relocation(mod
, info
);
3845 flush_module_icache(mod
);
3847 /* Now copy in args */
3848 mod
->args
= strndup_user(uargs
, ~0UL >> 1);
3849 if (IS_ERR(mod
->args
)) {
3850 err
= PTR_ERR(mod
->args
);
3851 goto free_arch_cleanup
;
3854 dynamic_debug_setup(mod
, info
->debug
, info
->num_debug
);
3856 /* Ftrace init must be called in the MODULE_STATE_UNFORMED state */
3857 ftrace_module_init(mod
);
3859 /* Finally it's fully formed, ready to start executing. */
3860 err
= complete_formation(mod
, info
);
3862 goto ddebug_cleanup
;
3864 err
= prepare_coming_module(mod
);
3868 /* Module is ready to execute: parsing args may do that. */
3869 after_dashes
= parse_args(mod
->name
, mod
->args
, mod
->kp
, mod
->num_kp
,
3871 unknown_module_param_cb
);
3872 if (IS_ERR(after_dashes
)) {
3873 err
= PTR_ERR(after_dashes
);
3874 goto coming_cleanup
;
3875 } else if (after_dashes
) {
3876 pr_warn("%s: parameters '%s' after `--' ignored\n",
3877 mod
->name
, after_dashes
);
3880 /* Link in to sysfs. */
3881 err
= mod_sysfs_setup(mod
, info
, mod
->kp
, mod
->num_kp
);
3883 goto coming_cleanup
;
3885 if (is_livepatch_module(mod
)) {
3886 err
= copy_module_elf(mod
, info
);
3891 /* Get rid of temporary copy. */
3895 trace_module_load(mod
);
3897 return do_init_module(mod
);
3900 mod_sysfs_teardown(mod
);
3902 mod
->state
= MODULE_STATE_GOING
;
3903 destroy_params(mod
->kp
, mod
->num_kp
);
3904 blocking_notifier_call_chain(&module_notify_list
,
3905 MODULE_STATE_GOING
, mod
);
3906 klp_module_going(mod
);
3908 /* module_bug_cleanup needs module_mutex protection */
3909 mutex_lock(&module_mutex
);
3910 module_bug_cleanup(mod
);
3911 mutex_unlock(&module_mutex
);
3914 ftrace_release_mod(mod
);
3915 dynamic_debug_remove(mod
, info
->debug
);
3919 module_arch_cleanup(mod
);
3923 module_unload_free(mod
);
3925 mutex_lock(&module_mutex
);
3926 /* Unlink carefully: kallsyms could be walking list. */
3927 list_del_rcu(&mod
->list
);
3928 mod_tree_remove(mod
);
3929 wake_up_all(&module_wq
);
3930 /* Wait for RCU-sched synchronizing before releasing mod->list. */
3932 mutex_unlock(&module_mutex
);
3934 /* Free lock-classes; relies on the preceding sync_rcu() */
3935 lockdep_free_key_range(mod
->core_layout
.base
, mod
->core_layout
.size
);
3937 module_deallocate(mod
, info
);
3943 SYSCALL_DEFINE3(init_module
, void __user
*, umod
,
3944 unsigned long, len
, const char __user
*, uargs
)
3947 struct load_info info
= { };
3949 err
= may_init_module();
3953 pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
3956 err
= copy_module_from_user(umod
, len
, &info
);
3960 return load_module(&info
, uargs
, 0);
3963 SYSCALL_DEFINE3(finit_module
, int, fd
, const char __user
*, uargs
, int, flags
)
3965 struct load_info info
= { };
3970 err
= may_init_module();
3974 pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd
, uargs
, flags
);
3976 if (flags
& ~(MODULE_INIT_IGNORE_MODVERSIONS
3977 |MODULE_INIT_IGNORE_VERMAGIC
))
3980 err
= kernel_read_file_from_fd(fd
, &hdr
, &size
, INT_MAX
,
3987 return load_module(&info
, uargs
, flags
);
3990 static inline int within(unsigned long addr
, void *start
, unsigned long size
)
3992 return ((void *)addr
>= start
&& (void *)addr
< start
+ size
);
3995 #ifdef CONFIG_KALLSYMS
3997 * This ignores the intensely annoying "mapping symbols" found
3998 * in ARM ELF files: $a, $t and $d.
4000 static inline int is_arm_mapping_symbol(const char *str
)
4002 if (str
[0] == '.' && str
[1] == 'L')
4004 return str
[0] == '$' && strchr("axtd", str
[1])
4005 && (str
[2] == '\0' || str
[2] == '.');
4008 static const char *kallsyms_symbol_name(struct mod_kallsyms
*kallsyms
, unsigned int symnum
)
4010 return kallsyms
->strtab
+ kallsyms
->symtab
[symnum
].st_name
;
4014 * Given a module and address, find the corresponding symbol and return its name
4015 * while providing its size and offset if needed.
4017 static const char *find_kallsyms_symbol(struct module
*mod
,
4019 unsigned long *size
,
4020 unsigned long *offset
)
4022 unsigned int i
, best
= 0;
4023 unsigned long nextval
, bestval
;
4024 struct mod_kallsyms
*kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
4026 /* At worse, next value is at end of module */
4027 if (within_module_init(addr
, mod
))
4028 nextval
= (unsigned long)mod
->init_layout
.base
+mod
->init_layout
.text_size
;
4030 nextval
= (unsigned long)mod
->core_layout
.base
+mod
->core_layout
.text_size
;
4032 bestval
= kallsyms_symbol_value(&kallsyms
->symtab
[best
]);
4034 /* Scan for closest preceding symbol, and next symbol. (ELF
4035 starts real symbols at 1). */
4036 for (i
= 1; i
< kallsyms
->num_symtab
; i
++) {
4037 const Elf_Sym
*sym
= &kallsyms
->symtab
[i
];
4038 unsigned long thisval
= kallsyms_symbol_value(sym
);
4040 if (sym
->st_shndx
== SHN_UNDEF
)
4043 /* We ignore unnamed symbols: they're uninformative
4044 * and inserted at a whim. */
4045 if (*kallsyms_symbol_name(kallsyms
, i
) == '\0'
4046 || is_arm_mapping_symbol(kallsyms_symbol_name(kallsyms
, i
)))
4049 if (thisval
<= addr
&& thisval
> bestval
) {
4053 if (thisval
> addr
&& thisval
< nextval
)
4061 *size
= nextval
- bestval
;
4063 *offset
= addr
- bestval
;
4065 return kallsyms_symbol_name(kallsyms
, best
);
4068 void * __weak
dereference_module_function_descriptor(struct module
*mod
,
4074 /* For kallsyms to ask for address resolution. NULL means not found. Careful
4075 * not to lock to avoid deadlock on oopses, simply disable preemption. */
4076 const char *module_address_lookup(unsigned long addr
,
4077 unsigned long *size
,
4078 unsigned long *offset
,
4082 const char *ret
= NULL
;
4086 mod
= __module_address(addr
);
4089 *modname
= mod
->name
;
4091 ret
= find_kallsyms_symbol(mod
, addr
, size
, offset
);
4093 /* Make a copy in here where it's safe */
4095 strncpy(namebuf
, ret
, KSYM_NAME_LEN
- 1);
4103 int lookup_module_symbol_name(unsigned long addr
, char *symname
)
4108 list_for_each_entry_rcu(mod
, &modules
, list
) {
4109 if (mod
->state
== MODULE_STATE_UNFORMED
)
4111 if (within_module(addr
, mod
)) {
4114 sym
= find_kallsyms_symbol(mod
, addr
, NULL
, NULL
);
4118 strlcpy(symname
, sym
, KSYM_NAME_LEN
);
4128 int lookup_module_symbol_attrs(unsigned long addr
, unsigned long *size
,
4129 unsigned long *offset
, char *modname
, char *name
)
4134 list_for_each_entry_rcu(mod
, &modules
, list
) {
4135 if (mod
->state
== MODULE_STATE_UNFORMED
)
4137 if (within_module(addr
, mod
)) {
4140 sym
= find_kallsyms_symbol(mod
, addr
, size
, offset
);
4144 strlcpy(modname
, mod
->name
, MODULE_NAME_LEN
);
4146 strlcpy(name
, sym
, KSYM_NAME_LEN
);
4156 int module_get_kallsym(unsigned int symnum
, unsigned long *value
, char *type
,
4157 char *name
, char *module_name
, int *exported
)
4162 list_for_each_entry_rcu(mod
, &modules
, list
) {
4163 struct mod_kallsyms
*kallsyms
;
4165 if (mod
->state
== MODULE_STATE_UNFORMED
)
4167 kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
4168 if (symnum
< kallsyms
->num_symtab
) {
4169 const Elf_Sym
*sym
= &kallsyms
->symtab
[symnum
];
4171 *value
= kallsyms_symbol_value(sym
);
4172 *type
= kallsyms
->typetab
[symnum
];
4173 strlcpy(name
, kallsyms_symbol_name(kallsyms
, symnum
), KSYM_NAME_LEN
);
4174 strlcpy(module_name
, mod
->name
, MODULE_NAME_LEN
);
4175 *exported
= is_exported(name
, *value
, mod
);
4179 symnum
-= kallsyms
->num_symtab
;
4185 /* Given a module and name of symbol, find and return the symbol's value */
4186 static unsigned long find_kallsyms_symbol_value(struct module
*mod
, const char *name
)
4189 struct mod_kallsyms
*kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
4191 for (i
= 0; i
< kallsyms
->num_symtab
; i
++) {
4192 const Elf_Sym
*sym
= &kallsyms
->symtab
[i
];
4194 if (strcmp(name
, kallsyms_symbol_name(kallsyms
, i
)) == 0 &&
4195 sym
->st_shndx
!= SHN_UNDEF
)
4196 return kallsyms_symbol_value(sym
);
4201 /* Look for this name: can be of form module:name. */
4202 unsigned long module_kallsyms_lookup_name(const char *name
)
4206 unsigned long ret
= 0;
4208 /* Don't lock: we're in enough trouble already. */
4210 if ((colon
= strnchr(name
, MODULE_NAME_LEN
, ':')) != NULL
) {
4211 if ((mod
= find_module_all(name
, colon
- name
, false)) != NULL
)
4212 ret
= find_kallsyms_symbol_value(mod
, colon
+1);
4214 list_for_each_entry_rcu(mod
, &modules
, list
) {
4215 if (mod
->state
== MODULE_STATE_UNFORMED
)
4217 if ((ret
= find_kallsyms_symbol_value(mod
, name
)) != 0)
4225 int module_kallsyms_on_each_symbol(int (*fn
)(void *, const char *,
4226 struct module
*, unsigned long),
4233 module_assert_mutex();
4235 list_for_each_entry(mod
, &modules
, list
) {
4236 /* We hold module_mutex: no need for rcu_dereference_sched */
4237 struct mod_kallsyms
*kallsyms
= mod
->kallsyms
;
4239 if (mod
->state
== MODULE_STATE_UNFORMED
)
4241 for (i
= 0; i
< kallsyms
->num_symtab
; i
++) {
4242 const Elf_Sym
*sym
= &kallsyms
->symtab
[i
];
4244 if (sym
->st_shndx
== SHN_UNDEF
)
4247 ret
= fn(data
, kallsyms_symbol_name(kallsyms
, i
),
4248 mod
, kallsyms_symbol_value(sym
));
4255 #endif /* CONFIG_KALLSYMS */
4257 /* Maximum number of characters written by module_flags() */
4258 #define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4)
4260 /* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */
4261 static char *module_flags(struct module
*mod
, char *buf
)
4265 BUG_ON(mod
->state
== MODULE_STATE_UNFORMED
);
4267 mod
->state
== MODULE_STATE_GOING
||
4268 mod
->state
== MODULE_STATE_COMING
) {
4270 bx
+= module_flags_taint(mod
, buf
+ bx
);
4271 /* Show a - for module-is-being-unloaded */
4272 if (mod
->state
== MODULE_STATE_GOING
)
4274 /* Show a + for module-is-being-loaded */
4275 if (mod
->state
== MODULE_STATE_COMING
)
4284 #ifdef CONFIG_PROC_FS
4285 /* Called by the /proc file system to return a list of modules. */
4286 static void *m_start(struct seq_file
*m
, loff_t
*pos
)
4288 mutex_lock(&module_mutex
);
4289 return seq_list_start(&modules
, *pos
);
4292 static void *m_next(struct seq_file
*m
, void *p
, loff_t
*pos
)
4294 return seq_list_next(p
, &modules
, pos
);
4297 static void m_stop(struct seq_file
*m
, void *p
)
4299 mutex_unlock(&module_mutex
);
4302 static int m_show(struct seq_file
*m
, void *p
)
4304 struct module
*mod
= list_entry(p
, struct module
, list
);
4305 char buf
[MODULE_FLAGS_BUF_SIZE
];
4308 /* We always ignore unformed modules. */
4309 if (mod
->state
== MODULE_STATE_UNFORMED
)
4312 seq_printf(m
, "%s %u",
4313 mod
->name
, mod
->init_layout
.size
+ mod
->core_layout
.size
);
4314 print_unload_info(m
, mod
);
4316 /* Informative for users. */
4317 seq_printf(m
, " %s",
4318 mod
->state
== MODULE_STATE_GOING
? "Unloading" :
4319 mod
->state
== MODULE_STATE_COMING
? "Loading" :
4321 /* Used by oprofile and other similar tools. */
4322 value
= m
->private ? NULL
: mod
->core_layout
.base
;
4323 seq_printf(m
, " 0x%px", value
);
4327 seq_printf(m
, " %s", module_flags(mod
, buf
));
4333 /* Format: modulename size refcount deps address
4335 Where refcount is a number or -, and deps is a comma-separated list
4338 static const struct seq_operations modules_op
= {
4346 * This also sets the "private" pointer to non-NULL if the
4347 * kernel pointers should be hidden (so you can just test
4348 * "m->private" to see if you should keep the values private).
4350 * We use the same logic as for /proc/kallsyms.
4352 static int modules_open(struct inode
*inode
, struct file
*file
)
4354 int err
= seq_open(file
, &modules_op
);
4357 struct seq_file
*m
= file
->private_data
;
4358 m
->private = kallsyms_show_value() ? NULL
: (void *)8ul;
4364 static const struct proc_ops modules_proc_ops
= {
4365 .proc_flags
= PROC_ENTRY_PERMANENT
,
4366 .proc_open
= modules_open
,
4367 .proc_read
= seq_read
,
4368 .proc_lseek
= seq_lseek
,
4369 .proc_release
= seq_release
,
4372 static int __init
proc_modules_init(void)
4374 proc_create("modules", 0, NULL
, &modules_proc_ops
);
4377 module_init(proc_modules_init
);
4380 /* Given an address, look for it in the module exception tables. */
4381 const struct exception_table_entry
*search_module_extables(unsigned long addr
)
4383 const struct exception_table_entry
*e
= NULL
;
4387 mod
= __module_address(addr
);
4391 if (!mod
->num_exentries
)
4394 e
= search_extable(mod
->extable
,
4401 * Now, if we found one, we are running inside it now, hence
4402 * we cannot unload the module, hence no refcnt needed.
4408 * is_module_address - is this address inside a module?
4409 * @addr: the address to check.
4411 * See is_module_text_address() if you simply want to see if the address
4412 * is code (not data).
4414 bool is_module_address(unsigned long addr
)
4419 ret
= __module_address(addr
) != NULL
;
4426 * __module_address - get the module which contains an address.
4427 * @addr: the address.
4429 * Must be called with preempt disabled or module mutex held so that
4430 * module doesn't get freed during this.
4432 struct module
*__module_address(unsigned long addr
)
4436 if (addr
< module_addr_min
|| addr
> module_addr_max
)
4439 module_assert_mutex_or_preempt();
4441 mod
= mod_find(addr
);
4443 BUG_ON(!within_module(addr
, mod
));
4444 if (mod
->state
== MODULE_STATE_UNFORMED
)
4449 EXPORT_SYMBOL_GPL(__module_address
);
4452 * is_module_text_address - is this address inside module code?
4453 * @addr: the address to check.
4455 * See is_module_address() if you simply want to see if the address is
4456 * anywhere in a module. See kernel_text_address() for testing if an
4457 * address corresponds to kernel or module code.
4459 bool is_module_text_address(unsigned long addr
)
4464 ret
= __module_text_address(addr
) != NULL
;
4471 * __module_text_address - get the module whose code contains an address.
4472 * @addr: the address.
4474 * Must be called with preempt disabled or module mutex held so that
4475 * module doesn't get freed during this.
4477 struct module
*__module_text_address(unsigned long addr
)
4479 struct module
*mod
= __module_address(addr
);
4481 /* Make sure it's within the text section. */
4482 if (!within(addr
, mod
->init_layout
.base
, mod
->init_layout
.text_size
)
4483 && !within(addr
, mod
->core_layout
.base
, mod
->core_layout
.text_size
))
4488 EXPORT_SYMBOL_GPL(__module_text_address
);
4490 /* Don't grab lock, we're oopsing. */
4491 void print_modules(void)
4494 char buf
[MODULE_FLAGS_BUF_SIZE
];
4496 printk(KERN_DEFAULT
"Modules linked in:");
4497 /* Most callers should already have preempt disabled, but make sure */
4499 list_for_each_entry_rcu(mod
, &modules
, list
) {
4500 if (mod
->state
== MODULE_STATE_UNFORMED
)
4502 pr_cont(" %s%s", mod
->name
, module_flags(mod
, buf
));
4505 if (last_unloaded_module
[0])
4506 pr_cont(" [last unloaded: %s]", last_unloaded_module
);
4510 #ifdef CONFIG_MODVERSIONS
4511 /* Generate the signature for all relevant module structures here.
4512 * If these change, we don't want to try to parse the module. */
4513 void module_layout(struct module
*mod
,
4514 struct modversion_info
*ver
,
4515 struct kernel_param
*kp
,
4516 struct kernel_symbol
*ks
,
4517 struct tracepoint
* const *tp
)
4520 EXPORT_SYMBOL(module_layout
);