1 // SPDX-License-Identifier: GPL-2.0-or-later
3 Copyright (C) 2002 Richard Henderson
4 Copyright (C) 2001 Rusty Russell, 2002, 2010 Rusty Russell IBM.
7 #include <linux/export.h>
8 #include <linux/extable.h>
9 #include <linux/moduleloader.h>
10 #include <linux/module_signature.h>
11 #include <linux/trace_events.h>
12 #include <linux/init.h>
13 #include <linux/kallsyms.h>
14 #include <linux/file.h>
16 #include <linux/sysfs.h>
17 #include <linux/kernel.h>
18 #include <linux/slab.h>
19 #include <linux/vmalloc.h>
20 #include <linux/elf.h>
21 #include <linux/proc_fs.h>
22 #include <linux/security.h>
23 #include <linux/seq_file.h>
24 #include <linux/syscalls.h>
25 #include <linux/fcntl.h>
26 #include <linux/rcupdate.h>
27 #include <linux/capability.h>
28 #include <linux/cpu.h>
29 #include <linux/moduleparam.h>
30 #include <linux/errno.h>
31 #include <linux/err.h>
32 #include <linux/vermagic.h>
33 #include <linux/notifier.h>
34 #include <linux/sched.h>
35 #include <linux/device.h>
36 #include <linux/string.h>
37 #include <linux/mutex.h>
38 #include <linux/rculist.h>
39 #include <linux/uaccess.h>
40 #include <asm/cacheflush.h>
41 #include <linux/set_memory.h>
42 #include <asm/mmu_context.h>
43 #include <linux/license.h>
44 #include <asm/sections.h>
45 #include <linux/tracepoint.h>
46 #include <linux/ftrace.h>
47 #include <linux/livepatch.h>
48 #include <linux/async.h>
49 #include <linux/percpu.h>
50 #include <linux/kmemleak.h>
51 #include <linux/jump_label.h>
52 #include <linux/pfn.h>
53 #include <linux/bsearch.h>
54 #include <linux/dynamic_debug.h>
55 #include <linux/audit.h>
56 #include <uapi/linux/module.h>
57 #include "module-internal.h"
59 #define CREATE_TRACE_POINTS
60 #include <trace/events/module.h>
62 #ifndef ARCH_SHF_SMALL
63 #define ARCH_SHF_SMALL 0
67 * Modules' sections will be aligned on page boundaries
68 * to ensure complete separation of code and data, but
69 * only when CONFIG_ARCH_HAS_STRICT_MODULE_RWX=y
71 #ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX
72 # define debug_align(X) ALIGN(X, PAGE_SIZE)
74 # define debug_align(X) (X)
77 /* If this is set, the section belongs in the init part of the module */
78 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
82 * 1) List of modules (also safely readable with preempt_disable),
83 * 2) module_use links,
84 * 3) module_addr_min/module_addr_max.
85 * (delete and add uses RCU list operations). */
86 DEFINE_MUTEX(module_mutex
);
87 EXPORT_SYMBOL_GPL(module_mutex
);
88 static LIST_HEAD(modules
);
90 /* Work queue for freeing init sections in success case */
91 static struct work_struct init_free_wq
;
92 static struct llist_head init_free_list
;
94 #ifdef CONFIG_MODULES_TREE_LOOKUP
97 * Use a latched RB-tree for __module_address(); this allows us to use
98 * RCU-sched lookups of the address from any context.
100 * This is conditional on PERF_EVENTS || TRACING because those can really hit
101 * __module_address() hard by doing a lot of stack unwinding; potentially from
105 static __always_inline
unsigned long __mod_tree_val(struct latch_tree_node
*n
)
107 struct module_layout
*layout
= container_of(n
, struct module_layout
, mtn
.node
);
109 return (unsigned long)layout
->base
;
112 static __always_inline
unsigned long __mod_tree_size(struct latch_tree_node
*n
)
114 struct module_layout
*layout
= container_of(n
, struct module_layout
, mtn
.node
);
116 return (unsigned long)layout
->size
;
119 static __always_inline
bool
120 mod_tree_less(struct latch_tree_node
*a
, struct latch_tree_node
*b
)
122 return __mod_tree_val(a
) < __mod_tree_val(b
);
125 static __always_inline
int
126 mod_tree_comp(void *key
, struct latch_tree_node
*n
)
128 unsigned long val
= (unsigned long)key
;
129 unsigned long start
, end
;
131 start
= __mod_tree_val(n
);
135 end
= start
+ __mod_tree_size(n
);
142 static const struct latch_tree_ops mod_tree_ops
= {
143 .less
= mod_tree_less
,
144 .comp
= mod_tree_comp
,
147 static struct mod_tree_root
{
148 struct latch_tree_root root
;
149 unsigned long addr_min
;
150 unsigned long addr_max
;
151 } mod_tree __cacheline_aligned
= {
155 #define module_addr_min mod_tree.addr_min
156 #define module_addr_max mod_tree.addr_max
158 static noinline
void __mod_tree_insert(struct mod_tree_node
*node
)
160 latch_tree_insert(&node
->node
, &mod_tree
.root
, &mod_tree_ops
);
163 static void __mod_tree_remove(struct mod_tree_node
*node
)
165 latch_tree_erase(&node
->node
, &mod_tree
.root
, &mod_tree_ops
);
169 * These modifications: insert, remove_init and remove; are serialized by the
172 static void mod_tree_insert(struct module
*mod
)
174 mod
->core_layout
.mtn
.mod
= mod
;
175 mod
->init_layout
.mtn
.mod
= mod
;
177 __mod_tree_insert(&mod
->core_layout
.mtn
);
178 if (mod
->init_layout
.size
)
179 __mod_tree_insert(&mod
->init_layout
.mtn
);
182 static void mod_tree_remove_init(struct module
*mod
)
184 if (mod
->init_layout
.size
)
185 __mod_tree_remove(&mod
->init_layout
.mtn
);
188 static void mod_tree_remove(struct module
*mod
)
190 __mod_tree_remove(&mod
->core_layout
.mtn
);
191 mod_tree_remove_init(mod
);
194 static struct module
*mod_find(unsigned long addr
)
196 struct latch_tree_node
*ltn
;
198 ltn
= latch_tree_find((void *)addr
, &mod_tree
.root
, &mod_tree_ops
);
202 return container_of(ltn
, struct mod_tree_node
, node
)->mod
;
205 #else /* MODULES_TREE_LOOKUP */
207 static unsigned long module_addr_min
= -1UL, module_addr_max
= 0;
209 static void mod_tree_insert(struct module
*mod
) { }
210 static void mod_tree_remove_init(struct module
*mod
) { }
211 static void mod_tree_remove(struct module
*mod
) { }
213 static struct module
*mod_find(unsigned long addr
)
217 list_for_each_entry_rcu(mod
, &modules
, list
,
218 lockdep_is_held(&module_mutex
)) {
219 if (within_module(addr
, mod
))
226 #endif /* MODULES_TREE_LOOKUP */
229 * Bounds of module text, for speeding up __module_address.
230 * Protected by module_mutex.
232 static void __mod_update_bounds(void *base
, unsigned int size
)
234 unsigned long min
= (unsigned long)base
;
235 unsigned long max
= min
+ size
;
237 if (min
< module_addr_min
)
238 module_addr_min
= min
;
239 if (max
> module_addr_max
)
240 module_addr_max
= max
;
243 static void mod_update_bounds(struct module
*mod
)
245 __mod_update_bounds(mod
->core_layout
.base
, mod
->core_layout
.size
);
246 if (mod
->init_layout
.size
)
247 __mod_update_bounds(mod
->init_layout
.base
, mod
->init_layout
.size
);
250 #ifdef CONFIG_KGDB_KDB
251 struct list_head
*kdb_modules
= &modules
; /* kdb needs the list of modules */
252 #endif /* CONFIG_KGDB_KDB */
254 static void module_assert_mutex(void)
256 lockdep_assert_held(&module_mutex
);
259 static void module_assert_mutex_or_preempt(void)
261 #ifdef CONFIG_LOCKDEP
262 if (unlikely(!debug_locks
))
265 WARN_ON_ONCE(!rcu_read_lock_sched_held() &&
266 !lockdep_is_held(&module_mutex
));
270 static bool sig_enforce
= IS_ENABLED(CONFIG_MODULE_SIG_FORCE
);
271 module_param(sig_enforce
, bool_enable_only
, 0644);
274 * Export sig_enforce kernel cmdline parameter to allow other subsystems rely
275 * on that instead of directly to CONFIG_MODULE_SIG_FORCE config.
277 bool is_module_sig_enforced(void)
281 EXPORT_SYMBOL(is_module_sig_enforced
);
283 void set_module_sig_enforced(void)
288 /* Block module loading/unloading? */
289 int modules_disabled
= 0;
290 core_param(nomodule
, modules_disabled
, bint
, 0);
292 /* Waiting for a module to finish initializing? */
293 static DECLARE_WAIT_QUEUE_HEAD(module_wq
);
295 static BLOCKING_NOTIFIER_HEAD(module_notify_list
);
297 int register_module_notifier(struct notifier_block
*nb
)
299 return blocking_notifier_chain_register(&module_notify_list
, nb
);
301 EXPORT_SYMBOL(register_module_notifier
);
303 int unregister_module_notifier(struct notifier_block
*nb
)
305 return blocking_notifier_chain_unregister(&module_notify_list
, nb
);
307 EXPORT_SYMBOL(unregister_module_notifier
);
310 * We require a truly strong try_module_get(): 0 means success.
311 * Otherwise an error is returned due to ongoing or failed
312 * initialization etc.
314 static inline int strong_try_module_get(struct module
*mod
)
316 BUG_ON(mod
&& mod
->state
== MODULE_STATE_UNFORMED
);
317 if (mod
&& mod
->state
== MODULE_STATE_COMING
)
319 if (try_module_get(mod
))
325 static inline void add_taint_module(struct module
*mod
, unsigned flag
,
326 enum lockdep_ok lockdep_ok
)
328 add_taint(flag
, lockdep_ok
);
329 set_bit(flag
, &mod
->taints
);
333 * A thread that wants to hold a reference to a module only while it
334 * is running can call this to safely exit. nfsd and lockd use this.
336 void __noreturn
__module_put_and_exit(struct module
*mod
, long code
)
341 EXPORT_SYMBOL(__module_put_and_exit
);
343 /* Find a module section: 0 means not found. */
344 static unsigned int find_sec(const struct load_info
*info
, const char *name
)
348 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
349 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
350 /* Alloc bit cleared means "ignore it." */
351 if ((shdr
->sh_flags
& SHF_ALLOC
)
352 && strcmp(info
->secstrings
+ shdr
->sh_name
, name
) == 0)
358 /* Find a module section, or NULL. */
359 static void *section_addr(const struct load_info
*info
, const char *name
)
361 /* Section 0 has sh_addr 0. */
362 return (void *)info
->sechdrs
[find_sec(info
, name
)].sh_addr
;
365 /* Find a module section, or NULL. Fill in number of "objects" in section. */
366 static void *section_objs(const struct load_info
*info
,
371 unsigned int sec
= find_sec(info
, name
);
373 /* Section 0 has sh_addr 0 and sh_size 0. */
374 *num
= info
->sechdrs
[sec
].sh_size
/ object_size
;
375 return (void *)info
->sechdrs
[sec
].sh_addr
;
378 /* Provided by the linker */
379 extern const struct kernel_symbol __start___ksymtab
[];
380 extern const struct kernel_symbol __stop___ksymtab
[];
381 extern const struct kernel_symbol __start___ksymtab_gpl
[];
382 extern const struct kernel_symbol __stop___ksymtab_gpl
[];
383 extern const struct kernel_symbol __start___ksymtab_gpl_future
[];
384 extern const struct kernel_symbol __stop___ksymtab_gpl_future
[];
385 extern const s32 __start___kcrctab
[];
386 extern const s32 __start___kcrctab_gpl
[];
387 extern const s32 __start___kcrctab_gpl_future
[];
388 #ifdef CONFIG_UNUSED_SYMBOLS
389 extern const struct kernel_symbol __start___ksymtab_unused
[];
390 extern const struct kernel_symbol __stop___ksymtab_unused
[];
391 extern const struct kernel_symbol __start___ksymtab_unused_gpl
[];
392 extern const struct kernel_symbol __stop___ksymtab_unused_gpl
[];
393 extern const s32 __start___kcrctab_unused
[];
394 extern const s32 __start___kcrctab_unused_gpl
[];
397 #ifndef CONFIG_MODVERSIONS
398 #define symversion(base, idx) NULL
400 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
403 static bool each_symbol_in_section(const struct symsearch
*arr
,
404 unsigned int arrsize
,
405 struct module
*owner
,
406 bool (*fn
)(const struct symsearch
*syms
,
407 struct module
*owner
,
413 for (j
= 0; j
< arrsize
; j
++) {
414 if (fn(&arr
[j
], owner
, data
))
421 /* Returns true as soon as fn returns true, otherwise false. */
422 bool each_symbol_section(bool (*fn
)(const struct symsearch
*arr
,
423 struct module
*owner
,
428 static const struct symsearch arr
[] = {
429 { __start___ksymtab
, __stop___ksymtab
, __start___kcrctab
,
430 NOT_GPL_ONLY
, false },
431 { __start___ksymtab_gpl
, __stop___ksymtab_gpl
,
432 __start___kcrctab_gpl
,
434 { __start___ksymtab_gpl_future
, __stop___ksymtab_gpl_future
,
435 __start___kcrctab_gpl_future
,
436 WILL_BE_GPL_ONLY
, false },
437 #ifdef CONFIG_UNUSED_SYMBOLS
438 { __start___ksymtab_unused
, __stop___ksymtab_unused
,
439 __start___kcrctab_unused
,
440 NOT_GPL_ONLY
, true },
441 { __start___ksymtab_unused_gpl
, __stop___ksymtab_unused_gpl
,
442 __start___kcrctab_unused_gpl
,
447 module_assert_mutex_or_preempt();
449 if (each_symbol_in_section(arr
, ARRAY_SIZE(arr
), NULL
, fn
, data
))
452 list_for_each_entry_rcu(mod
, &modules
, list
,
453 lockdep_is_held(&module_mutex
)) {
454 struct symsearch arr
[] = {
455 { mod
->syms
, mod
->syms
+ mod
->num_syms
, mod
->crcs
,
456 NOT_GPL_ONLY
, false },
457 { mod
->gpl_syms
, mod
->gpl_syms
+ mod
->num_gpl_syms
,
460 { mod
->gpl_future_syms
,
461 mod
->gpl_future_syms
+ mod
->num_gpl_future_syms
,
462 mod
->gpl_future_crcs
,
463 WILL_BE_GPL_ONLY
, false },
464 #ifdef CONFIG_UNUSED_SYMBOLS
466 mod
->unused_syms
+ mod
->num_unused_syms
,
468 NOT_GPL_ONLY
, true },
469 { mod
->unused_gpl_syms
,
470 mod
->unused_gpl_syms
+ mod
->num_unused_gpl_syms
,
471 mod
->unused_gpl_crcs
,
476 if (mod
->state
== MODULE_STATE_UNFORMED
)
479 if (each_symbol_in_section(arr
, ARRAY_SIZE(arr
), mod
, fn
, data
))
484 EXPORT_SYMBOL_GPL(each_symbol_section
);
486 struct find_symbol_arg
{
493 struct module
*owner
;
495 const struct kernel_symbol
*sym
;
498 static bool check_exported_symbol(const struct symsearch
*syms
,
499 struct module
*owner
,
500 unsigned int symnum
, void *data
)
502 struct find_symbol_arg
*fsa
= data
;
505 if (syms
->licence
== GPL_ONLY
)
507 if (syms
->licence
== WILL_BE_GPL_ONLY
&& fsa
->warn
) {
508 pr_warn("Symbol %s is being used by a non-GPL module, "
509 "which will not be allowed in the future\n",
514 #ifdef CONFIG_UNUSED_SYMBOLS
515 if (syms
->unused
&& fsa
->warn
) {
516 pr_warn("Symbol %s is marked as UNUSED, however this module is "
517 "using it.\n", fsa
->name
);
518 pr_warn("This symbol will go away in the future.\n");
519 pr_warn("Please evaluate if this is the right api to use and "
520 "if it really is, submit a report to the linux kernel "
521 "mailing list together with submitting your code for "
527 fsa
->crc
= symversion(syms
->crcs
, symnum
);
528 fsa
->sym
= &syms
->start
[symnum
];
532 static unsigned long kernel_symbol_value(const struct kernel_symbol
*sym
)
534 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
535 return (unsigned long)offset_to_ptr(&sym
->value_offset
);
541 static const char *kernel_symbol_name(const struct kernel_symbol
*sym
)
543 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
544 return offset_to_ptr(&sym
->name_offset
);
550 static const char *kernel_symbol_namespace(const struct kernel_symbol
*sym
)
552 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
553 if (!sym
->namespace_offset
)
555 return offset_to_ptr(&sym
->namespace_offset
);
557 return sym
->namespace;
561 static int cmp_name(const void *name
, const void *sym
)
563 return strcmp(name
, kernel_symbol_name(sym
));
566 static bool find_exported_symbol_in_section(const struct symsearch
*syms
,
567 struct module
*owner
,
570 struct find_symbol_arg
*fsa
= data
;
571 struct kernel_symbol
*sym
;
573 sym
= bsearch(fsa
->name
, syms
->start
, syms
->stop
- syms
->start
,
574 sizeof(struct kernel_symbol
), cmp_name
);
576 if (sym
!= NULL
&& check_exported_symbol(syms
, owner
,
577 sym
- syms
->start
, data
))
583 /* Find an exported symbol and return it, along with, (optional) crc and
584 * (optional) module which owns it. Needs preempt disabled or module_mutex. */
585 const struct kernel_symbol
*find_symbol(const char *name
,
586 struct module
**owner
,
591 struct find_symbol_arg fsa
;
597 if (each_symbol_section(find_exported_symbol_in_section
, &fsa
)) {
605 pr_debug("Failed to find symbol %s\n", name
);
608 EXPORT_SYMBOL_GPL(find_symbol
);
611 * Search for module by name: must hold module_mutex (or preempt disabled
612 * for read-only access).
614 static struct module
*find_module_all(const char *name
, size_t len
,
619 module_assert_mutex_or_preempt();
621 list_for_each_entry_rcu(mod
, &modules
, list
,
622 lockdep_is_held(&module_mutex
)) {
623 if (!even_unformed
&& mod
->state
== MODULE_STATE_UNFORMED
)
625 if (strlen(mod
->name
) == len
&& !memcmp(mod
->name
, name
, len
))
631 struct module
*find_module(const char *name
)
633 module_assert_mutex();
634 return find_module_all(name
, strlen(name
), false);
636 EXPORT_SYMBOL_GPL(find_module
);
640 static inline void __percpu
*mod_percpu(struct module
*mod
)
645 static int percpu_modalloc(struct module
*mod
, struct load_info
*info
)
647 Elf_Shdr
*pcpusec
= &info
->sechdrs
[info
->index
.pcpu
];
648 unsigned long align
= pcpusec
->sh_addralign
;
650 if (!pcpusec
->sh_size
)
653 if (align
> PAGE_SIZE
) {
654 pr_warn("%s: per-cpu alignment %li > %li\n",
655 mod
->name
, align
, PAGE_SIZE
);
659 mod
->percpu
= __alloc_reserved_percpu(pcpusec
->sh_size
, align
);
661 pr_warn("%s: Could not allocate %lu bytes percpu data\n",
662 mod
->name
, (unsigned long)pcpusec
->sh_size
);
665 mod
->percpu_size
= pcpusec
->sh_size
;
669 static void percpu_modfree(struct module
*mod
)
671 free_percpu(mod
->percpu
);
674 static unsigned int find_pcpusec(struct load_info
*info
)
676 return find_sec(info
, ".data..percpu");
679 static void percpu_modcopy(struct module
*mod
,
680 const void *from
, unsigned long size
)
684 for_each_possible_cpu(cpu
)
685 memcpy(per_cpu_ptr(mod
->percpu
, cpu
), from
, size
);
688 bool __is_module_percpu_address(unsigned long addr
, unsigned long *can_addr
)
695 list_for_each_entry_rcu(mod
, &modules
, list
) {
696 if (mod
->state
== MODULE_STATE_UNFORMED
)
698 if (!mod
->percpu_size
)
700 for_each_possible_cpu(cpu
) {
701 void *start
= per_cpu_ptr(mod
->percpu
, cpu
);
702 void *va
= (void *)addr
;
704 if (va
>= start
&& va
< start
+ mod
->percpu_size
) {
706 *can_addr
= (unsigned long) (va
- start
);
707 *can_addr
+= (unsigned long)
708 per_cpu_ptr(mod
->percpu
,
722 * is_module_percpu_address - test whether address is from module static percpu
723 * @addr: address to test
725 * Test whether @addr belongs to module static percpu area.
728 * %true if @addr is from module static percpu area
730 bool is_module_percpu_address(unsigned long addr
)
732 return __is_module_percpu_address(addr
, NULL
);
735 #else /* ... !CONFIG_SMP */
737 static inline void __percpu
*mod_percpu(struct module
*mod
)
741 static int percpu_modalloc(struct module
*mod
, struct load_info
*info
)
743 /* UP modules shouldn't have this section: ENOMEM isn't quite right */
744 if (info
->sechdrs
[info
->index
.pcpu
].sh_size
!= 0)
748 static inline void percpu_modfree(struct module
*mod
)
751 static unsigned int find_pcpusec(struct load_info
*info
)
755 static inline void percpu_modcopy(struct module
*mod
,
756 const void *from
, unsigned long size
)
758 /* pcpusec should be 0, and size of that section should be 0. */
761 bool is_module_percpu_address(unsigned long addr
)
766 bool __is_module_percpu_address(unsigned long addr
, unsigned long *can_addr
)
771 #endif /* CONFIG_SMP */
773 #define MODINFO_ATTR(field) \
774 static void setup_modinfo_##field(struct module *mod, const char *s) \
776 mod->field = kstrdup(s, GFP_KERNEL); \
778 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
779 struct module_kobject *mk, char *buffer) \
781 return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \
783 static int modinfo_##field##_exists(struct module *mod) \
785 return mod->field != NULL; \
787 static void free_modinfo_##field(struct module *mod) \
792 static struct module_attribute modinfo_##field = { \
793 .attr = { .name = __stringify(field), .mode = 0444 }, \
794 .show = show_modinfo_##field, \
795 .setup = setup_modinfo_##field, \
796 .test = modinfo_##field##_exists, \
797 .free = free_modinfo_##field, \
800 MODINFO_ATTR(version
);
801 MODINFO_ATTR(srcversion
);
803 static char last_unloaded_module
[MODULE_NAME_LEN
+1];
805 #ifdef CONFIG_MODULE_UNLOAD
807 EXPORT_TRACEPOINT_SYMBOL(module_get
);
809 /* MODULE_REF_BASE is the base reference count by kmodule loader. */
810 #define MODULE_REF_BASE 1
812 /* Init the unload section of the module. */
813 static int module_unload_init(struct module
*mod
)
816 * Initialize reference counter to MODULE_REF_BASE.
817 * refcnt == 0 means module is going.
819 atomic_set(&mod
->refcnt
, MODULE_REF_BASE
);
821 INIT_LIST_HEAD(&mod
->source_list
);
822 INIT_LIST_HEAD(&mod
->target_list
);
824 /* Hold reference count during initialization. */
825 atomic_inc(&mod
->refcnt
);
830 /* Does a already use b? */
831 static int already_uses(struct module
*a
, struct module
*b
)
833 struct module_use
*use
;
835 list_for_each_entry(use
, &b
->source_list
, source_list
) {
836 if (use
->source
== a
) {
837 pr_debug("%s uses %s!\n", a
->name
, b
->name
);
841 pr_debug("%s does not use %s!\n", a
->name
, b
->name
);
847 * - we add 'a' as a "source", 'b' as a "target" of module use
848 * - the module_use is added to the list of 'b' sources (so
849 * 'b' can walk the list to see who sourced them), and of 'a'
850 * targets (so 'a' can see what modules it targets).
852 static int add_module_usage(struct module
*a
, struct module
*b
)
854 struct module_use
*use
;
856 pr_debug("Allocating new usage for %s.\n", a
->name
);
857 use
= kmalloc(sizeof(*use
), GFP_ATOMIC
);
863 list_add(&use
->source_list
, &b
->source_list
);
864 list_add(&use
->target_list
, &a
->target_list
);
868 /* Module a uses b: caller needs module_mutex() */
869 int ref_module(struct module
*a
, struct module
*b
)
873 if (b
== NULL
|| already_uses(a
, b
))
876 /* If module isn't available, we fail. */
877 err
= strong_try_module_get(b
);
881 err
= add_module_usage(a
, b
);
888 EXPORT_SYMBOL_GPL(ref_module
);
890 /* Clear the unload stuff of the module. */
891 static void module_unload_free(struct module
*mod
)
893 struct module_use
*use
, *tmp
;
895 mutex_lock(&module_mutex
);
896 list_for_each_entry_safe(use
, tmp
, &mod
->target_list
, target_list
) {
897 struct module
*i
= use
->target
;
898 pr_debug("%s unusing %s\n", mod
->name
, i
->name
);
900 list_del(&use
->source_list
);
901 list_del(&use
->target_list
);
904 mutex_unlock(&module_mutex
);
907 #ifdef CONFIG_MODULE_FORCE_UNLOAD
908 static inline int try_force_unload(unsigned int flags
)
910 int ret
= (flags
& O_TRUNC
);
912 add_taint(TAINT_FORCED_RMMOD
, LOCKDEP_NOW_UNRELIABLE
);
916 static inline int try_force_unload(unsigned int flags
)
920 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
922 /* Try to release refcount of module, 0 means success. */
923 static int try_release_module_ref(struct module
*mod
)
927 /* Try to decrement refcnt which we set at loading */
928 ret
= atomic_sub_return(MODULE_REF_BASE
, &mod
->refcnt
);
931 /* Someone can put this right now, recover with checking */
932 ret
= atomic_add_unless(&mod
->refcnt
, MODULE_REF_BASE
, 0);
937 static int try_stop_module(struct module
*mod
, int flags
, int *forced
)
939 /* If it's not unused, quit unless we're forcing. */
940 if (try_release_module_ref(mod
) != 0) {
941 *forced
= try_force_unload(flags
);
946 /* Mark it as dying. */
947 mod
->state
= MODULE_STATE_GOING
;
953 * module_refcount - return the refcount or -1 if unloading
955 * @mod: the module we're checking
958 * -1 if the module is in the process of unloading
959 * otherwise the number of references in the kernel to the module
961 int module_refcount(struct module
*mod
)
963 return atomic_read(&mod
->refcnt
) - MODULE_REF_BASE
;
965 EXPORT_SYMBOL(module_refcount
);
967 /* This exists whether we can unload or not */
968 static void free_module(struct module
*mod
);
970 SYSCALL_DEFINE2(delete_module
, const char __user
*, name_user
,
974 char name
[MODULE_NAME_LEN
];
977 if (!capable(CAP_SYS_MODULE
) || modules_disabled
)
980 if (strncpy_from_user(name
, name_user
, MODULE_NAME_LEN
-1) < 0)
982 name
[MODULE_NAME_LEN
-1] = '\0';
984 audit_log_kern_module(name
);
986 if (mutex_lock_interruptible(&module_mutex
) != 0)
989 mod
= find_module(name
);
995 if (!list_empty(&mod
->source_list
)) {
996 /* Other modules depend on us: get rid of them first. */
1001 /* Doing init or already dying? */
1002 if (mod
->state
!= MODULE_STATE_LIVE
) {
1003 /* FIXME: if (force), slam module count damn the torpedoes */
1004 pr_debug("%s already dying\n", mod
->name
);
1009 /* If it has an init func, it must have an exit func to unload */
1010 if (mod
->init
&& !mod
->exit
) {
1011 forced
= try_force_unload(flags
);
1013 /* This module can't be removed */
1019 /* Stop the machine so refcounts can't move and disable module. */
1020 ret
= try_stop_module(mod
, flags
, &forced
);
1024 mutex_unlock(&module_mutex
);
1025 /* Final destruction now no one is using it. */
1026 if (mod
->exit
!= NULL
)
1028 blocking_notifier_call_chain(&module_notify_list
,
1029 MODULE_STATE_GOING
, mod
);
1030 klp_module_going(mod
);
1031 ftrace_release_mod(mod
);
1033 async_synchronize_full();
1035 /* Store the name of the last unloaded module for diagnostic purposes */
1036 strlcpy(last_unloaded_module
, mod
->name
, sizeof(last_unloaded_module
));
1039 /* someone could wait for the module in add_unformed_module() */
1040 wake_up_all(&module_wq
);
1043 mutex_unlock(&module_mutex
);
1047 static inline void print_unload_info(struct seq_file
*m
, struct module
*mod
)
1049 struct module_use
*use
;
1050 int printed_something
= 0;
1052 seq_printf(m
, " %i ", module_refcount(mod
));
1055 * Always include a trailing , so userspace can differentiate
1056 * between this and the old multi-field proc format.
1058 list_for_each_entry(use
, &mod
->source_list
, source_list
) {
1059 printed_something
= 1;
1060 seq_printf(m
, "%s,", use
->source
->name
);
1063 if (mod
->init
!= NULL
&& mod
->exit
== NULL
) {
1064 printed_something
= 1;
1065 seq_puts(m
, "[permanent],");
1068 if (!printed_something
)
1072 void __symbol_put(const char *symbol
)
1074 struct module
*owner
;
1077 if (!find_symbol(symbol
, &owner
, NULL
, true, false))
1082 EXPORT_SYMBOL(__symbol_put
);
1084 /* Note this assumes addr is a function, which it currently always is. */
1085 void symbol_put_addr(void *addr
)
1087 struct module
*modaddr
;
1088 unsigned long a
= (unsigned long)dereference_function_descriptor(addr
);
1090 if (core_kernel_text(a
))
1094 * Even though we hold a reference on the module; we still need to
1095 * disable preemption in order to safely traverse the data structure.
1098 modaddr
= __module_text_address(a
);
1100 module_put(modaddr
);
1103 EXPORT_SYMBOL_GPL(symbol_put_addr
);
1105 static ssize_t
show_refcnt(struct module_attribute
*mattr
,
1106 struct module_kobject
*mk
, char *buffer
)
1108 return sprintf(buffer
, "%i\n", module_refcount(mk
->mod
));
1111 static struct module_attribute modinfo_refcnt
=
1112 __ATTR(refcnt
, 0444, show_refcnt
, NULL
);
1114 void __module_get(struct module
*module
)
1118 atomic_inc(&module
->refcnt
);
1119 trace_module_get(module
, _RET_IP_
);
1123 EXPORT_SYMBOL(__module_get
);
1125 bool try_module_get(struct module
*module
)
1131 /* Note: here, we can fail to get a reference */
1132 if (likely(module_is_live(module
) &&
1133 atomic_inc_not_zero(&module
->refcnt
) != 0))
1134 trace_module_get(module
, _RET_IP_
);
1142 EXPORT_SYMBOL(try_module_get
);
1144 void module_put(struct module
*module
)
1150 ret
= atomic_dec_if_positive(&module
->refcnt
);
1151 WARN_ON(ret
< 0); /* Failed to put refcount */
1152 trace_module_put(module
, _RET_IP_
);
1156 EXPORT_SYMBOL(module_put
);
1158 #else /* !CONFIG_MODULE_UNLOAD */
1159 static inline void print_unload_info(struct seq_file
*m
, struct module
*mod
)
1161 /* We don't know the usage count, or what modules are using. */
1162 seq_puts(m
, " - -");
1165 static inline void module_unload_free(struct module
*mod
)
1169 int ref_module(struct module
*a
, struct module
*b
)
1171 return strong_try_module_get(b
);
1173 EXPORT_SYMBOL_GPL(ref_module
);
1175 static inline int module_unload_init(struct module
*mod
)
1179 #endif /* CONFIG_MODULE_UNLOAD */
1181 static size_t module_flags_taint(struct module
*mod
, char *buf
)
1186 for (i
= 0; i
< TAINT_FLAGS_COUNT
; i
++) {
1187 if (taint_flags
[i
].module
&& test_bit(i
, &mod
->taints
))
1188 buf
[l
++] = taint_flags
[i
].c_true
;
1194 static ssize_t
show_initstate(struct module_attribute
*mattr
,
1195 struct module_kobject
*mk
, char *buffer
)
1197 const char *state
= "unknown";
1199 switch (mk
->mod
->state
) {
1200 case MODULE_STATE_LIVE
:
1203 case MODULE_STATE_COMING
:
1206 case MODULE_STATE_GOING
:
1212 return sprintf(buffer
, "%s\n", state
);
1215 static struct module_attribute modinfo_initstate
=
1216 __ATTR(initstate
, 0444, show_initstate
, NULL
);
1218 static ssize_t
store_uevent(struct module_attribute
*mattr
,
1219 struct module_kobject
*mk
,
1220 const char *buffer
, size_t count
)
1224 rc
= kobject_synth_uevent(&mk
->kobj
, buffer
, count
);
1225 return rc
? rc
: count
;
1228 struct module_attribute module_uevent
=
1229 __ATTR(uevent
, 0200, NULL
, store_uevent
);
1231 static ssize_t
show_coresize(struct module_attribute
*mattr
,
1232 struct module_kobject
*mk
, char *buffer
)
1234 return sprintf(buffer
, "%u\n", mk
->mod
->core_layout
.size
);
1237 static struct module_attribute modinfo_coresize
=
1238 __ATTR(coresize
, 0444, show_coresize
, NULL
);
1240 static ssize_t
show_initsize(struct module_attribute
*mattr
,
1241 struct module_kobject
*mk
, char *buffer
)
1243 return sprintf(buffer
, "%u\n", mk
->mod
->init_layout
.size
);
1246 static struct module_attribute modinfo_initsize
=
1247 __ATTR(initsize
, 0444, show_initsize
, NULL
);
1249 static ssize_t
show_taint(struct module_attribute
*mattr
,
1250 struct module_kobject
*mk
, char *buffer
)
1254 l
= module_flags_taint(mk
->mod
, buffer
);
1259 static struct module_attribute modinfo_taint
=
1260 __ATTR(taint
, 0444, show_taint
, NULL
);
1262 static struct module_attribute
*modinfo_attrs
[] = {
1265 &modinfo_srcversion
,
1270 #ifdef CONFIG_MODULE_UNLOAD
1276 static const char vermagic
[] = VERMAGIC_STRING
;
1278 static int try_to_force_load(struct module
*mod
, const char *reason
)
1280 #ifdef CONFIG_MODULE_FORCE_LOAD
1281 if (!test_taint(TAINT_FORCED_MODULE
))
1282 pr_warn("%s: %s: kernel tainted.\n", mod
->name
, reason
);
1283 add_taint_module(mod
, TAINT_FORCED_MODULE
, LOCKDEP_NOW_UNRELIABLE
);
1290 #ifdef CONFIG_MODVERSIONS
1292 static u32
resolve_rel_crc(const s32
*crc
)
1294 return *(u32
*)((void *)crc
+ *crc
);
1297 static int check_version(const struct load_info
*info
,
1298 const char *symname
,
1302 Elf_Shdr
*sechdrs
= info
->sechdrs
;
1303 unsigned int versindex
= info
->index
.vers
;
1304 unsigned int i
, num_versions
;
1305 struct modversion_info
*versions
;
1307 /* Exporting module didn't supply crcs? OK, we're already tainted. */
1311 /* No versions at all? modprobe --force does this. */
1313 return try_to_force_load(mod
, symname
) == 0;
1315 versions
= (void *) sechdrs
[versindex
].sh_addr
;
1316 num_versions
= sechdrs
[versindex
].sh_size
1317 / sizeof(struct modversion_info
);
1319 for (i
= 0; i
< num_versions
; i
++) {
1322 if (strcmp(versions
[i
].name
, symname
) != 0)
1325 if (IS_ENABLED(CONFIG_MODULE_REL_CRCS
))
1326 crcval
= resolve_rel_crc(crc
);
1329 if (versions
[i
].crc
== crcval
)
1331 pr_debug("Found checksum %X vs module %lX\n",
1332 crcval
, versions
[i
].crc
);
1336 /* Broken toolchain. Warn once, then let it go.. */
1337 pr_warn_once("%s: no symbol version for %s\n", info
->name
, symname
);
1341 pr_warn("%s: disagrees about version of symbol %s\n",
1342 info
->name
, symname
);
1346 static inline int check_modstruct_version(const struct load_info
*info
,
1352 * Since this should be found in kernel (which can't be removed), no
1353 * locking is necessary -- use preempt_disable() to placate lockdep.
1356 if (!find_symbol("module_layout", NULL
, &crc
, true, false)) {
1361 return check_version(info
, "module_layout", mod
, crc
);
1364 /* First part is kernel version, which we ignore if module has crcs. */
1365 static inline int same_magic(const char *amagic
, const char *bmagic
,
1369 amagic
+= strcspn(amagic
, " ");
1370 bmagic
+= strcspn(bmagic
, " ");
1372 return strcmp(amagic
, bmagic
) == 0;
1375 static inline int check_version(const struct load_info
*info
,
1376 const char *symname
,
1383 static inline int check_modstruct_version(const struct load_info
*info
,
1389 static inline int same_magic(const char *amagic
, const char *bmagic
,
1392 return strcmp(amagic
, bmagic
) == 0;
1394 #endif /* CONFIG_MODVERSIONS */
1396 static char *get_modinfo(const struct load_info
*info
, const char *tag
);
1397 static char *get_next_modinfo(const struct load_info
*info
, const char *tag
,
1400 static int verify_namespace_is_imported(const struct load_info
*info
,
1401 const struct kernel_symbol
*sym
,
1404 const char *namespace;
1405 char *imported_namespace
;
1407 namespace = kernel_symbol_namespace(sym
);
1409 imported_namespace
= get_modinfo(info
, "import_ns");
1410 while (imported_namespace
) {
1411 if (strcmp(namespace, imported_namespace
) == 0)
1413 imported_namespace
= get_next_modinfo(
1414 info
, "import_ns", imported_namespace
);
1416 #ifdef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS
1421 "%s: module uses symbol (%s) from namespace %s, but does not import it.\n",
1422 mod
->name
, kernel_symbol_name(sym
), namespace);
1423 #ifndef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS
1431 /* Resolve a symbol for this module. I.e. if we find one, record usage. */
1432 static const struct kernel_symbol
*resolve_symbol(struct module
*mod
,
1433 const struct load_info
*info
,
1437 struct module
*owner
;
1438 const struct kernel_symbol
*sym
;
1443 * The module_mutex should not be a heavily contended lock;
1444 * if we get the occasional sleep here, we'll go an extra iteration
1445 * in the wait_event_interruptible(), which is harmless.
1447 sched_annotate_sleep();
1448 mutex_lock(&module_mutex
);
1449 sym
= find_symbol(name
, &owner
, &crc
,
1450 !(mod
->taints
& (1 << TAINT_PROPRIETARY_MODULE
)), true);
1454 if (!check_version(info
, name
, mod
, crc
)) {
1455 sym
= ERR_PTR(-EINVAL
);
1459 err
= verify_namespace_is_imported(info
, sym
, mod
);
1465 err
= ref_module(mod
, owner
);
1472 /* We must make copy under the lock if we failed to get ref. */
1473 strncpy(ownername
, module_name(owner
), MODULE_NAME_LEN
);
1475 mutex_unlock(&module_mutex
);
1479 static const struct kernel_symbol
*
1480 resolve_symbol_wait(struct module
*mod
,
1481 const struct load_info
*info
,
1484 const struct kernel_symbol
*ksym
;
1485 char owner
[MODULE_NAME_LEN
];
1487 if (wait_event_interruptible_timeout(module_wq
,
1488 !IS_ERR(ksym
= resolve_symbol(mod
, info
, name
, owner
))
1489 || PTR_ERR(ksym
) != -EBUSY
,
1491 pr_warn("%s: gave up waiting for init of module %s.\n",
1498 * /sys/module/foo/sections stuff
1499 * J. Corbet <corbet@lwn.net>
1503 #ifdef CONFIG_KALLSYMS
1504 static inline bool sect_empty(const Elf_Shdr
*sect
)
1506 return !(sect
->sh_flags
& SHF_ALLOC
) || sect
->sh_size
== 0;
1509 struct module_sect_attr
{
1510 struct module_attribute mattr
;
1512 unsigned long address
;
1515 struct module_sect_attrs
{
1516 struct attribute_group grp
;
1517 unsigned int nsections
;
1518 struct module_sect_attr attrs
[0];
1521 static ssize_t
module_sect_show(struct module_attribute
*mattr
,
1522 struct module_kobject
*mk
, char *buf
)
1524 struct module_sect_attr
*sattr
=
1525 container_of(mattr
, struct module_sect_attr
, mattr
);
1526 return sprintf(buf
, "0x%px\n", kptr_restrict
< 2 ?
1527 (void *)sattr
->address
: NULL
);
1530 static void free_sect_attrs(struct module_sect_attrs
*sect_attrs
)
1532 unsigned int section
;
1534 for (section
= 0; section
< sect_attrs
->nsections
; section
++)
1535 kfree(sect_attrs
->attrs
[section
].name
);
1539 static void add_sect_attrs(struct module
*mod
, const struct load_info
*info
)
1541 unsigned int nloaded
= 0, i
, size
[2];
1542 struct module_sect_attrs
*sect_attrs
;
1543 struct module_sect_attr
*sattr
;
1544 struct attribute
**gattr
;
1546 /* Count loaded sections and allocate structures */
1547 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
1548 if (!sect_empty(&info
->sechdrs
[i
]))
1550 size
[0] = ALIGN(struct_size(sect_attrs
, attrs
, nloaded
),
1551 sizeof(sect_attrs
->grp
.attrs
[0]));
1552 size
[1] = (nloaded
+ 1) * sizeof(sect_attrs
->grp
.attrs
[0]);
1553 sect_attrs
= kzalloc(size
[0] + size
[1], GFP_KERNEL
);
1554 if (sect_attrs
== NULL
)
1557 /* Setup section attributes. */
1558 sect_attrs
->grp
.name
= "sections";
1559 sect_attrs
->grp
.attrs
= (void *)sect_attrs
+ size
[0];
1561 sect_attrs
->nsections
= 0;
1562 sattr
= §_attrs
->attrs
[0];
1563 gattr
= §_attrs
->grp
.attrs
[0];
1564 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++) {
1565 Elf_Shdr
*sec
= &info
->sechdrs
[i
];
1566 if (sect_empty(sec
))
1568 sattr
->address
= sec
->sh_addr
;
1569 sattr
->name
= kstrdup(info
->secstrings
+ sec
->sh_name
,
1571 if (sattr
->name
== NULL
)
1573 sect_attrs
->nsections
++;
1574 sysfs_attr_init(&sattr
->mattr
.attr
);
1575 sattr
->mattr
.show
= module_sect_show
;
1576 sattr
->mattr
.store
= NULL
;
1577 sattr
->mattr
.attr
.name
= sattr
->name
;
1578 sattr
->mattr
.attr
.mode
= S_IRUSR
;
1579 *(gattr
++) = &(sattr
++)->mattr
.attr
;
1583 if (sysfs_create_group(&mod
->mkobj
.kobj
, §_attrs
->grp
))
1586 mod
->sect_attrs
= sect_attrs
;
1589 free_sect_attrs(sect_attrs
);
1592 static void remove_sect_attrs(struct module
*mod
)
1594 if (mod
->sect_attrs
) {
1595 sysfs_remove_group(&mod
->mkobj
.kobj
,
1596 &mod
->sect_attrs
->grp
);
1597 /* We are positive that no one is using any sect attrs
1598 * at this point. Deallocate immediately. */
1599 free_sect_attrs(mod
->sect_attrs
);
1600 mod
->sect_attrs
= NULL
;
1605 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1608 struct module_notes_attrs
{
1609 struct kobject
*dir
;
1611 struct bin_attribute attrs
[0];
1614 static ssize_t
module_notes_read(struct file
*filp
, struct kobject
*kobj
,
1615 struct bin_attribute
*bin_attr
,
1616 char *buf
, loff_t pos
, size_t count
)
1619 * The caller checked the pos and count against our size.
1621 memcpy(buf
, bin_attr
->private + pos
, count
);
1625 static void free_notes_attrs(struct module_notes_attrs
*notes_attrs
,
1628 if (notes_attrs
->dir
) {
1630 sysfs_remove_bin_file(notes_attrs
->dir
,
1631 ¬es_attrs
->attrs
[i
]);
1632 kobject_put(notes_attrs
->dir
);
1637 static void add_notes_attrs(struct module
*mod
, const struct load_info
*info
)
1639 unsigned int notes
, loaded
, i
;
1640 struct module_notes_attrs
*notes_attrs
;
1641 struct bin_attribute
*nattr
;
1643 /* failed to create section attributes, so can't create notes */
1644 if (!mod
->sect_attrs
)
1647 /* Count notes sections and allocate structures. */
1649 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
1650 if (!sect_empty(&info
->sechdrs
[i
]) &&
1651 (info
->sechdrs
[i
].sh_type
== SHT_NOTE
))
1657 notes_attrs
= kzalloc(struct_size(notes_attrs
, attrs
, notes
),
1659 if (notes_attrs
== NULL
)
1662 notes_attrs
->notes
= notes
;
1663 nattr
= ¬es_attrs
->attrs
[0];
1664 for (loaded
= i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
1665 if (sect_empty(&info
->sechdrs
[i
]))
1667 if (info
->sechdrs
[i
].sh_type
== SHT_NOTE
) {
1668 sysfs_bin_attr_init(nattr
);
1669 nattr
->attr
.name
= mod
->sect_attrs
->attrs
[loaded
].name
;
1670 nattr
->attr
.mode
= S_IRUGO
;
1671 nattr
->size
= info
->sechdrs
[i
].sh_size
;
1672 nattr
->private = (void *) info
->sechdrs
[i
].sh_addr
;
1673 nattr
->read
= module_notes_read
;
1679 notes_attrs
->dir
= kobject_create_and_add("notes", &mod
->mkobj
.kobj
);
1680 if (!notes_attrs
->dir
)
1683 for (i
= 0; i
< notes
; ++i
)
1684 if (sysfs_create_bin_file(notes_attrs
->dir
,
1685 ¬es_attrs
->attrs
[i
]))
1688 mod
->notes_attrs
= notes_attrs
;
1692 free_notes_attrs(notes_attrs
, i
);
1695 static void remove_notes_attrs(struct module
*mod
)
1697 if (mod
->notes_attrs
)
1698 free_notes_attrs(mod
->notes_attrs
, mod
->notes_attrs
->notes
);
1703 static inline void add_sect_attrs(struct module
*mod
,
1704 const struct load_info
*info
)
1708 static inline void remove_sect_attrs(struct module
*mod
)
1712 static inline void add_notes_attrs(struct module
*mod
,
1713 const struct load_info
*info
)
1717 static inline void remove_notes_attrs(struct module
*mod
)
1720 #endif /* CONFIG_KALLSYMS */
1722 static void del_usage_links(struct module
*mod
)
1724 #ifdef CONFIG_MODULE_UNLOAD
1725 struct module_use
*use
;
1727 mutex_lock(&module_mutex
);
1728 list_for_each_entry(use
, &mod
->target_list
, target_list
)
1729 sysfs_remove_link(use
->target
->holders_dir
, mod
->name
);
1730 mutex_unlock(&module_mutex
);
1734 static int add_usage_links(struct module
*mod
)
1737 #ifdef CONFIG_MODULE_UNLOAD
1738 struct module_use
*use
;
1740 mutex_lock(&module_mutex
);
1741 list_for_each_entry(use
, &mod
->target_list
, target_list
) {
1742 ret
= sysfs_create_link(use
->target
->holders_dir
,
1743 &mod
->mkobj
.kobj
, mod
->name
);
1747 mutex_unlock(&module_mutex
);
1749 del_usage_links(mod
);
1754 static void module_remove_modinfo_attrs(struct module
*mod
, int end
);
1756 static int module_add_modinfo_attrs(struct module
*mod
)
1758 struct module_attribute
*attr
;
1759 struct module_attribute
*temp_attr
;
1763 mod
->modinfo_attrs
= kzalloc((sizeof(struct module_attribute
) *
1764 (ARRAY_SIZE(modinfo_attrs
) + 1)),
1766 if (!mod
->modinfo_attrs
)
1769 temp_attr
= mod
->modinfo_attrs
;
1770 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
1771 if (!attr
->test
|| attr
->test(mod
)) {
1772 memcpy(temp_attr
, attr
, sizeof(*temp_attr
));
1773 sysfs_attr_init(&temp_attr
->attr
);
1774 error
= sysfs_create_file(&mod
->mkobj
.kobj
,
1786 module_remove_modinfo_attrs(mod
, --i
);
1788 kfree(mod
->modinfo_attrs
);
1792 static void module_remove_modinfo_attrs(struct module
*mod
, int end
)
1794 struct module_attribute
*attr
;
1797 for (i
= 0; (attr
= &mod
->modinfo_attrs
[i
]); i
++) {
1798 if (end
>= 0 && i
> end
)
1800 /* pick a field to test for end of list */
1801 if (!attr
->attr
.name
)
1803 sysfs_remove_file(&mod
->mkobj
.kobj
, &attr
->attr
);
1807 kfree(mod
->modinfo_attrs
);
1810 static void mod_kobject_put(struct module
*mod
)
1812 DECLARE_COMPLETION_ONSTACK(c
);
1813 mod
->mkobj
.kobj_completion
= &c
;
1814 kobject_put(&mod
->mkobj
.kobj
);
1815 wait_for_completion(&c
);
1818 static int mod_sysfs_init(struct module
*mod
)
1821 struct kobject
*kobj
;
1823 if (!module_sysfs_initialized
) {
1824 pr_err("%s: module sysfs not initialized\n", mod
->name
);
1829 kobj
= kset_find_obj(module_kset
, mod
->name
);
1831 pr_err("%s: module is already loaded\n", mod
->name
);
1837 mod
->mkobj
.mod
= mod
;
1839 memset(&mod
->mkobj
.kobj
, 0, sizeof(mod
->mkobj
.kobj
));
1840 mod
->mkobj
.kobj
.kset
= module_kset
;
1841 err
= kobject_init_and_add(&mod
->mkobj
.kobj
, &module_ktype
, NULL
,
1844 mod_kobject_put(mod
);
1846 /* delay uevent until full sysfs population */
1851 static int mod_sysfs_setup(struct module
*mod
,
1852 const struct load_info
*info
,
1853 struct kernel_param
*kparam
,
1854 unsigned int num_params
)
1858 err
= mod_sysfs_init(mod
);
1862 mod
->holders_dir
= kobject_create_and_add("holders", &mod
->mkobj
.kobj
);
1863 if (!mod
->holders_dir
) {
1868 err
= module_param_sysfs_setup(mod
, kparam
, num_params
);
1870 goto out_unreg_holders
;
1872 err
= module_add_modinfo_attrs(mod
);
1874 goto out_unreg_param
;
1876 err
= add_usage_links(mod
);
1878 goto out_unreg_modinfo_attrs
;
1880 add_sect_attrs(mod
, info
);
1881 add_notes_attrs(mod
, info
);
1883 kobject_uevent(&mod
->mkobj
.kobj
, KOBJ_ADD
);
1886 out_unreg_modinfo_attrs
:
1887 module_remove_modinfo_attrs(mod
, -1);
1889 module_param_sysfs_remove(mod
);
1891 kobject_put(mod
->holders_dir
);
1893 mod_kobject_put(mod
);
1898 static void mod_sysfs_fini(struct module
*mod
)
1900 remove_notes_attrs(mod
);
1901 remove_sect_attrs(mod
);
1902 mod_kobject_put(mod
);
1905 static void init_param_lock(struct module
*mod
)
1907 mutex_init(&mod
->param_lock
);
1909 #else /* !CONFIG_SYSFS */
1911 static int mod_sysfs_setup(struct module
*mod
,
1912 const struct load_info
*info
,
1913 struct kernel_param
*kparam
,
1914 unsigned int num_params
)
1919 static void mod_sysfs_fini(struct module
*mod
)
1923 static void module_remove_modinfo_attrs(struct module
*mod
, int end
)
1927 static void del_usage_links(struct module
*mod
)
1931 static void init_param_lock(struct module
*mod
)
1934 #endif /* CONFIG_SYSFS */
1936 static void mod_sysfs_teardown(struct module
*mod
)
1938 del_usage_links(mod
);
1939 module_remove_modinfo_attrs(mod
, -1);
1940 module_param_sysfs_remove(mod
);
1941 kobject_put(mod
->mkobj
.drivers_dir
);
1942 kobject_put(mod
->holders_dir
);
1943 mod_sysfs_fini(mod
);
1946 #ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX
1948 * LKM RO/NX protection: protect module's text/ro-data
1949 * from modification and any data from execution.
1951 * General layout of module is:
1952 * [text] [read-only-data] [ro-after-init] [writable data]
1953 * text_size -----^ ^ ^ ^
1954 * ro_size ------------------------| | |
1955 * ro_after_init_size -----------------------------| |
1956 * size -----------------------------------------------------------|
1958 * These values are always page-aligned (as is base)
1960 static void frob_text(const struct module_layout
*layout
,
1961 int (*set_memory
)(unsigned long start
, int num_pages
))
1963 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1964 BUG_ON((unsigned long)layout
->text_size
& (PAGE_SIZE
-1));
1965 set_memory((unsigned long)layout
->base
,
1966 layout
->text_size
>> PAGE_SHIFT
);
1969 #ifdef CONFIG_STRICT_MODULE_RWX
1970 static void frob_rodata(const struct module_layout
*layout
,
1971 int (*set_memory
)(unsigned long start
, int num_pages
))
1973 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1974 BUG_ON((unsigned long)layout
->text_size
& (PAGE_SIZE
-1));
1975 BUG_ON((unsigned long)layout
->ro_size
& (PAGE_SIZE
-1));
1976 set_memory((unsigned long)layout
->base
+ layout
->text_size
,
1977 (layout
->ro_size
- layout
->text_size
) >> PAGE_SHIFT
);
1980 static void frob_ro_after_init(const struct module_layout
*layout
,
1981 int (*set_memory
)(unsigned long start
, int num_pages
))
1983 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1984 BUG_ON((unsigned long)layout
->ro_size
& (PAGE_SIZE
-1));
1985 BUG_ON((unsigned long)layout
->ro_after_init_size
& (PAGE_SIZE
-1));
1986 set_memory((unsigned long)layout
->base
+ layout
->ro_size
,
1987 (layout
->ro_after_init_size
- layout
->ro_size
) >> PAGE_SHIFT
);
1990 static void frob_writable_data(const struct module_layout
*layout
,
1991 int (*set_memory
)(unsigned long start
, int num_pages
))
1993 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1994 BUG_ON((unsigned long)layout
->ro_after_init_size
& (PAGE_SIZE
-1));
1995 BUG_ON((unsigned long)layout
->size
& (PAGE_SIZE
-1));
1996 set_memory((unsigned long)layout
->base
+ layout
->ro_after_init_size
,
1997 (layout
->size
- layout
->ro_after_init_size
) >> PAGE_SHIFT
);
2000 /* livepatching wants to disable read-only so it can frob module. */
2001 void module_disable_ro(const struct module
*mod
)
2003 if (!rodata_enabled
)
2006 frob_text(&mod
->core_layout
, set_memory_rw
);
2007 frob_rodata(&mod
->core_layout
, set_memory_rw
);
2008 frob_ro_after_init(&mod
->core_layout
, set_memory_rw
);
2009 frob_text(&mod
->init_layout
, set_memory_rw
);
2010 frob_rodata(&mod
->init_layout
, set_memory_rw
);
2013 void module_enable_ro(const struct module
*mod
, bool after_init
)
2015 if (!rodata_enabled
)
2018 set_vm_flush_reset_perms(mod
->core_layout
.base
);
2019 set_vm_flush_reset_perms(mod
->init_layout
.base
);
2020 frob_text(&mod
->core_layout
, set_memory_ro
);
2022 frob_rodata(&mod
->core_layout
, set_memory_ro
);
2023 frob_text(&mod
->init_layout
, set_memory_ro
);
2024 frob_rodata(&mod
->init_layout
, set_memory_ro
);
2027 frob_ro_after_init(&mod
->core_layout
, set_memory_ro
);
2030 static void module_enable_nx(const struct module
*mod
)
2032 frob_rodata(&mod
->core_layout
, set_memory_nx
);
2033 frob_ro_after_init(&mod
->core_layout
, set_memory_nx
);
2034 frob_writable_data(&mod
->core_layout
, set_memory_nx
);
2035 frob_rodata(&mod
->init_layout
, set_memory_nx
);
2036 frob_writable_data(&mod
->init_layout
, set_memory_nx
);
2039 /* Iterate through all modules and set each module's text as RW */
2040 void set_all_modules_text_rw(void)
2044 if (!rodata_enabled
)
2047 mutex_lock(&module_mutex
);
2048 list_for_each_entry_rcu(mod
, &modules
, list
) {
2049 if (mod
->state
== MODULE_STATE_UNFORMED
)
2052 frob_text(&mod
->core_layout
, set_memory_rw
);
2053 frob_text(&mod
->init_layout
, set_memory_rw
);
2055 mutex_unlock(&module_mutex
);
2058 /* Iterate through all modules and set each module's text as RO */
2059 void set_all_modules_text_ro(void)
2063 if (!rodata_enabled
)
2066 mutex_lock(&module_mutex
);
2067 list_for_each_entry_rcu(mod
, &modules
, list
) {
2069 * Ignore going modules since it's possible that ro
2070 * protection has already been disabled, otherwise we'll
2071 * run into protection faults at module deallocation.
2073 if (mod
->state
== MODULE_STATE_UNFORMED
||
2074 mod
->state
== MODULE_STATE_GOING
)
2077 frob_text(&mod
->core_layout
, set_memory_ro
);
2078 frob_text(&mod
->init_layout
, set_memory_ro
);
2080 mutex_unlock(&module_mutex
);
2082 #else /* !CONFIG_STRICT_MODULE_RWX */
2083 static void module_enable_nx(const struct module
*mod
) { }
2084 #endif /* CONFIG_STRICT_MODULE_RWX */
2085 static void module_enable_x(const struct module
*mod
)
2087 frob_text(&mod
->core_layout
, set_memory_x
);
2088 frob_text(&mod
->init_layout
, set_memory_x
);
2090 #else /* !CONFIG_ARCH_HAS_STRICT_MODULE_RWX */
2091 static void module_enable_nx(const struct module
*mod
) { }
2092 static void module_enable_x(const struct module
*mod
) { }
2093 #endif /* CONFIG_ARCH_HAS_STRICT_MODULE_RWX */
2096 #ifdef CONFIG_LIVEPATCH
2098 * Persist Elf information about a module. Copy the Elf header,
2099 * section header table, section string table, and symtab section
2100 * index from info to mod->klp_info.
2102 static int copy_module_elf(struct module
*mod
, struct load_info
*info
)
2104 unsigned int size
, symndx
;
2107 size
= sizeof(*mod
->klp_info
);
2108 mod
->klp_info
= kmalloc(size
, GFP_KERNEL
);
2109 if (mod
->klp_info
== NULL
)
2113 size
= sizeof(mod
->klp_info
->hdr
);
2114 memcpy(&mod
->klp_info
->hdr
, info
->hdr
, size
);
2116 /* Elf section header table */
2117 size
= sizeof(*info
->sechdrs
) * info
->hdr
->e_shnum
;
2118 mod
->klp_info
->sechdrs
= kmemdup(info
->sechdrs
, size
, GFP_KERNEL
);
2119 if (mod
->klp_info
->sechdrs
== NULL
) {
2124 /* Elf section name string table */
2125 size
= info
->sechdrs
[info
->hdr
->e_shstrndx
].sh_size
;
2126 mod
->klp_info
->secstrings
= kmemdup(info
->secstrings
, size
, GFP_KERNEL
);
2127 if (mod
->klp_info
->secstrings
== NULL
) {
2132 /* Elf symbol section index */
2133 symndx
= info
->index
.sym
;
2134 mod
->klp_info
->symndx
= symndx
;
2137 * For livepatch modules, core_kallsyms.symtab is a complete
2138 * copy of the original symbol table. Adjust sh_addr to point
2139 * to core_kallsyms.symtab since the copy of the symtab in module
2140 * init memory is freed at the end of do_init_module().
2142 mod
->klp_info
->sechdrs
[symndx
].sh_addr
= \
2143 (unsigned long) mod
->core_kallsyms
.symtab
;
2148 kfree(mod
->klp_info
->sechdrs
);
2150 kfree(mod
->klp_info
);
2154 static void free_module_elf(struct module
*mod
)
2156 kfree(mod
->klp_info
->sechdrs
);
2157 kfree(mod
->klp_info
->secstrings
);
2158 kfree(mod
->klp_info
);
2160 #else /* !CONFIG_LIVEPATCH */
2161 static int copy_module_elf(struct module
*mod
, struct load_info
*info
)
2166 static void free_module_elf(struct module
*mod
)
2169 #endif /* CONFIG_LIVEPATCH */
2171 void __weak
module_memfree(void *module_region
)
2174 * This memory may be RO, and freeing RO memory in an interrupt is not
2175 * supported by vmalloc.
2177 WARN_ON(in_interrupt());
2178 vfree(module_region
);
2181 void __weak
module_arch_cleanup(struct module
*mod
)
2185 void __weak
module_arch_freeing_init(struct module
*mod
)
2189 /* Free a module, remove from lists, etc. */
2190 static void free_module(struct module
*mod
)
2192 trace_module_free(mod
);
2194 mod_sysfs_teardown(mod
);
2196 /* We leave it in list to prevent duplicate loads, but make sure
2197 * that noone uses it while it's being deconstructed. */
2198 mutex_lock(&module_mutex
);
2199 mod
->state
= MODULE_STATE_UNFORMED
;
2200 mutex_unlock(&module_mutex
);
2202 /* Remove dynamic debug info */
2203 ddebug_remove_module(mod
->name
);
2205 /* Arch-specific cleanup. */
2206 module_arch_cleanup(mod
);
2208 /* Module unload stuff */
2209 module_unload_free(mod
);
2211 /* Free any allocated parameters. */
2212 destroy_params(mod
->kp
, mod
->num_kp
);
2214 if (is_livepatch_module(mod
))
2215 free_module_elf(mod
);
2217 /* Now we can delete it from the lists */
2218 mutex_lock(&module_mutex
);
2219 /* Unlink carefully: kallsyms could be walking list. */
2220 list_del_rcu(&mod
->list
);
2221 mod_tree_remove(mod
);
2222 /* Remove this module from bug list, this uses list_del_rcu */
2223 module_bug_cleanup(mod
);
2224 /* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */
2226 mutex_unlock(&module_mutex
);
2228 /* This may be empty, but that's OK */
2229 module_arch_freeing_init(mod
);
2230 module_memfree(mod
->init_layout
.base
);
2232 percpu_modfree(mod
);
2234 /* Free lock-classes; relies on the preceding sync_rcu(). */
2235 lockdep_free_key_range(mod
->core_layout
.base
, mod
->core_layout
.size
);
2237 /* Finally, free the core (containing the module structure) */
2238 module_memfree(mod
->core_layout
.base
);
2241 void *__symbol_get(const char *symbol
)
2243 struct module
*owner
;
2244 const struct kernel_symbol
*sym
;
2247 sym
= find_symbol(symbol
, &owner
, NULL
, true, true);
2248 if (sym
&& strong_try_module_get(owner
))
2252 return sym
? (void *)kernel_symbol_value(sym
) : NULL
;
2254 EXPORT_SYMBOL_GPL(__symbol_get
);
2257 * Ensure that an exported symbol [global namespace] does not already exist
2258 * in the kernel or in some other module's exported symbol table.
2260 * You must hold the module_mutex.
2262 static int verify_exported_symbols(struct module
*mod
)
2265 struct module
*owner
;
2266 const struct kernel_symbol
*s
;
2268 const struct kernel_symbol
*sym
;
2271 { mod
->syms
, mod
->num_syms
},
2272 { mod
->gpl_syms
, mod
->num_gpl_syms
},
2273 { mod
->gpl_future_syms
, mod
->num_gpl_future_syms
},
2274 #ifdef CONFIG_UNUSED_SYMBOLS
2275 { mod
->unused_syms
, mod
->num_unused_syms
},
2276 { mod
->unused_gpl_syms
, mod
->num_unused_gpl_syms
},
2280 for (i
= 0; i
< ARRAY_SIZE(arr
); i
++) {
2281 for (s
= arr
[i
].sym
; s
< arr
[i
].sym
+ arr
[i
].num
; s
++) {
2282 if (find_symbol(kernel_symbol_name(s
), &owner
, NULL
,
2284 pr_err("%s: exports duplicate symbol %s"
2286 mod
->name
, kernel_symbol_name(s
),
2287 module_name(owner
));
2295 /* Change all symbols so that st_value encodes the pointer directly. */
2296 static int simplify_symbols(struct module
*mod
, const struct load_info
*info
)
2298 Elf_Shdr
*symsec
= &info
->sechdrs
[info
->index
.sym
];
2299 Elf_Sym
*sym
= (void *)symsec
->sh_addr
;
2300 unsigned long secbase
;
2303 const struct kernel_symbol
*ksym
;
2305 for (i
= 1; i
< symsec
->sh_size
/ sizeof(Elf_Sym
); i
++) {
2306 const char *name
= info
->strtab
+ sym
[i
].st_name
;
2308 switch (sym
[i
].st_shndx
) {
2310 /* Ignore common symbols */
2311 if (!strncmp(name
, "__gnu_lto", 9))
2314 /* We compiled with -fno-common. These are not
2315 supposed to happen. */
2316 pr_debug("Common symbol: %s\n", name
);
2317 pr_warn("%s: please compile with -fno-common\n",
2323 /* Don't need to do anything */
2324 pr_debug("Absolute symbol: 0x%08lx\n",
2325 (long)sym
[i
].st_value
);
2329 /* Livepatch symbols are resolved by livepatch */
2333 ksym
= resolve_symbol_wait(mod
, info
, name
);
2334 /* Ok if resolved. */
2335 if (ksym
&& !IS_ERR(ksym
)) {
2336 sym
[i
].st_value
= kernel_symbol_value(ksym
);
2341 if (!ksym
&& ELF_ST_BIND(sym
[i
].st_info
) == STB_WEAK
)
2344 ret
= PTR_ERR(ksym
) ?: -ENOENT
;
2345 pr_warn("%s: Unknown symbol %s (err %d)\n",
2346 mod
->name
, name
, ret
);
2350 /* Divert to percpu allocation if a percpu var. */
2351 if (sym
[i
].st_shndx
== info
->index
.pcpu
)
2352 secbase
= (unsigned long)mod_percpu(mod
);
2354 secbase
= info
->sechdrs
[sym
[i
].st_shndx
].sh_addr
;
2355 sym
[i
].st_value
+= secbase
;
2363 static int apply_relocations(struct module
*mod
, const struct load_info
*info
)
2368 /* Now do relocations. */
2369 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2370 unsigned int infosec
= info
->sechdrs
[i
].sh_info
;
2372 /* Not a valid relocation section? */
2373 if (infosec
>= info
->hdr
->e_shnum
)
2376 /* Don't bother with non-allocated sections */
2377 if (!(info
->sechdrs
[infosec
].sh_flags
& SHF_ALLOC
))
2380 /* Livepatch relocation sections are applied by livepatch */
2381 if (info
->sechdrs
[i
].sh_flags
& SHF_RELA_LIVEPATCH
)
2384 if (info
->sechdrs
[i
].sh_type
== SHT_REL
)
2385 err
= apply_relocate(info
->sechdrs
, info
->strtab
,
2386 info
->index
.sym
, i
, mod
);
2387 else if (info
->sechdrs
[i
].sh_type
== SHT_RELA
)
2388 err
= apply_relocate_add(info
->sechdrs
, info
->strtab
,
2389 info
->index
.sym
, i
, mod
);
2396 /* Additional bytes needed by arch in front of individual sections */
2397 unsigned int __weak
arch_mod_section_prepend(struct module
*mod
,
2398 unsigned int section
)
2400 /* default implementation just returns zero */
2404 /* Update size with this section: return offset. */
2405 static long get_offset(struct module
*mod
, unsigned int *size
,
2406 Elf_Shdr
*sechdr
, unsigned int section
)
2410 *size
+= arch_mod_section_prepend(mod
, section
);
2411 ret
= ALIGN(*size
, sechdr
->sh_addralign
?: 1);
2412 *size
= ret
+ sechdr
->sh_size
;
2416 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
2417 might -- code, read-only data, read-write data, small data. Tally
2418 sizes, and place the offsets into sh_entsize fields: high bit means it
2420 static void layout_sections(struct module
*mod
, struct load_info
*info
)
2422 static unsigned long const masks
[][2] = {
2423 /* NOTE: all executable code must be the first section
2424 * in this array; otherwise modify the text_size
2425 * finder in the two loops below */
2426 { SHF_EXECINSTR
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2427 { SHF_ALLOC
, SHF_WRITE
| ARCH_SHF_SMALL
},
2428 { SHF_RO_AFTER_INIT
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2429 { SHF_WRITE
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2430 { ARCH_SHF_SMALL
| SHF_ALLOC
, 0 }
2434 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
2435 info
->sechdrs
[i
].sh_entsize
= ~0UL;
2437 pr_debug("Core section allocation order:\n");
2438 for (m
= 0; m
< ARRAY_SIZE(masks
); ++m
) {
2439 for (i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
2440 Elf_Shdr
*s
= &info
->sechdrs
[i
];
2441 const char *sname
= info
->secstrings
+ s
->sh_name
;
2443 if ((s
->sh_flags
& masks
[m
][0]) != masks
[m
][0]
2444 || (s
->sh_flags
& masks
[m
][1])
2445 || s
->sh_entsize
!= ~0UL
2446 || strstarts(sname
, ".init"))
2448 s
->sh_entsize
= get_offset(mod
, &mod
->core_layout
.size
, s
, i
);
2449 pr_debug("\t%s\n", sname
);
2452 case 0: /* executable */
2453 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2454 mod
->core_layout
.text_size
= mod
->core_layout
.size
;
2456 case 1: /* RO: text and ro-data */
2457 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2458 mod
->core_layout
.ro_size
= mod
->core_layout
.size
;
2460 case 2: /* RO after init */
2461 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2462 mod
->core_layout
.ro_after_init_size
= mod
->core_layout
.size
;
2464 case 4: /* whole core */
2465 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2470 pr_debug("Init section allocation order:\n");
2471 for (m
= 0; m
< ARRAY_SIZE(masks
); ++m
) {
2472 for (i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
2473 Elf_Shdr
*s
= &info
->sechdrs
[i
];
2474 const char *sname
= info
->secstrings
+ s
->sh_name
;
2476 if ((s
->sh_flags
& masks
[m
][0]) != masks
[m
][0]
2477 || (s
->sh_flags
& masks
[m
][1])
2478 || s
->sh_entsize
!= ~0UL
2479 || !strstarts(sname
, ".init"))
2481 s
->sh_entsize
= (get_offset(mod
, &mod
->init_layout
.size
, s
, i
)
2482 | INIT_OFFSET_MASK
);
2483 pr_debug("\t%s\n", sname
);
2486 case 0: /* executable */
2487 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2488 mod
->init_layout
.text_size
= mod
->init_layout
.size
;
2490 case 1: /* RO: text and ro-data */
2491 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2492 mod
->init_layout
.ro_size
= mod
->init_layout
.size
;
2496 * RO after init doesn't apply to init_layout (only
2497 * core_layout), so it just takes the value of ro_size.
2499 mod
->init_layout
.ro_after_init_size
= mod
->init_layout
.ro_size
;
2501 case 4: /* whole init */
2502 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2508 static void set_license(struct module
*mod
, const char *license
)
2511 license
= "unspecified";
2513 if (!license_is_gpl_compatible(license
)) {
2514 if (!test_taint(TAINT_PROPRIETARY_MODULE
))
2515 pr_warn("%s: module license '%s' taints kernel.\n",
2516 mod
->name
, license
);
2517 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
2518 LOCKDEP_NOW_UNRELIABLE
);
2522 /* Parse tag=value strings from .modinfo section */
2523 static char *next_string(char *string
, unsigned long *secsize
)
2525 /* Skip non-zero chars */
2528 if ((*secsize
)-- <= 1)
2532 /* Skip any zero padding. */
2533 while (!string
[0]) {
2535 if ((*secsize
)-- <= 1)
2541 static char *get_next_modinfo(const struct load_info
*info
, const char *tag
,
2545 unsigned int taglen
= strlen(tag
);
2546 Elf_Shdr
*infosec
= &info
->sechdrs
[info
->index
.info
];
2547 unsigned long size
= infosec
->sh_size
;
2550 * get_modinfo() calls made before rewrite_section_headers()
2551 * must use sh_offset, as sh_addr isn't set!
2553 char *modinfo
= (char *)info
->hdr
+ infosec
->sh_offset
;
2556 size
-= prev
- modinfo
;
2557 modinfo
= next_string(prev
, &size
);
2560 for (p
= modinfo
; p
; p
= next_string(p
, &size
)) {
2561 if (strncmp(p
, tag
, taglen
) == 0 && p
[taglen
] == '=')
2562 return p
+ taglen
+ 1;
2567 static char *get_modinfo(const struct load_info
*info
, const char *tag
)
2569 return get_next_modinfo(info
, tag
, NULL
);
2572 static void setup_modinfo(struct module
*mod
, struct load_info
*info
)
2574 struct module_attribute
*attr
;
2577 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
2579 attr
->setup(mod
, get_modinfo(info
, attr
->attr
.name
));
2583 static void free_modinfo(struct module
*mod
)
2585 struct module_attribute
*attr
;
2588 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
2594 #ifdef CONFIG_KALLSYMS
2596 /* Lookup exported symbol in given range of kernel_symbols */
2597 static const struct kernel_symbol
*lookup_exported_symbol(const char *name
,
2598 const struct kernel_symbol
*start
,
2599 const struct kernel_symbol
*stop
)
2601 return bsearch(name
, start
, stop
- start
,
2602 sizeof(struct kernel_symbol
), cmp_name
);
2605 static int is_exported(const char *name
, unsigned long value
,
2606 const struct module
*mod
)
2608 const struct kernel_symbol
*ks
;
2610 ks
= lookup_exported_symbol(name
, __start___ksymtab
, __stop___ksymtab
);
2612 ks
= lookup_exported_symbol(name
, mod
->syms
, mod
->syms
+ mod
->num_syms
);
2614 return ks
!= NULL
&& kernel_symbol_value(ks
) == value
;
2618 static char elf_type(const Elf_Sym
*sym
, const struct load_info
*info
)
2620 const Elf_Shdr
*sechdrs
= info
->sechdrs
;
2622 if (ELF_ST_BIND(sym
->st_info
) == STB_WEAK
) {
2623 if (ELF_ST_TYPE(sym
->st_info
) == STT_OBJECT
)
2628 if (sym
->st_shndx
== SHN_UNDEF
)
2630 if (sym
->st_shndx
== SHN_ABS
|| sym
->st_shndx
== info
->index
.pcpu
)
2632 if (sym
->st_shndx
>= SHN_LORESERVE
)
2634 if (sechdrs
[sym
->st_shndx
].sh_flags
& SHF_EXECINSTR
)
2636 if (sechdrs
[sym
->st_shndx
].sh_flags
& SHF_ALLOC
2637 && sechdrs
[sym
->st_shndx
].sh_type
!= SHT_NOBITS
) {
2638 if (!(sechdrs
[sym
->st_shndx
].sh_flags
& SHF_WRITE
))
2640 else if (sechdrs
[sym
->st_shndx
].sh_flags
& ARCH_SHF_SMALL
)
2645 if (sechdrs
[sym
->st_shndx
].sh_type
== SHT_NOBITS
) {
2646 if (sechdrs
[sym
->st_shndx
].sh_flags
& ARCH_SHF_SMALL
)
2651 if (strstarts(info
->secstrings
+ sechdrs
[sym
->st_shndx
].sh_name
,
2658 static bool is_core_symbol(const Elf_Sym
*src
, const Elf_Shdr
*sechdrs
,
2659 unsigned int shnum
, unsigned int pcpundx
)
2661 const Elf_Shdr
*sec
;
2663 if (src
->st_shndx
== SHN_UNDEF
2664 || src
->st_shndx
>= shnum
2668 #ifdef CONFIG_KALLSYMS_ALL
2669 if (src
->st_shndx
== pcpundx
)
2673 sec
= sechdrs
+ src
->st_shndx
;
2674 if (!(sec
->sh_flags
& SHF_ALLOC
)
2675 #ifndef CONFIG_KALLSYMS_ALL
2676 || !(sec
->sh_flags
& SHF_EXECINSTR
)
2678 || (sec
->sh_entsize
& INIT_OFFSET_MASK
))
2685 * We only allocate and copy the strings needed by the parts of symtab
2686 * we keep. This is simple, but has the effect of making multiple
2687 * copies of duplicates. We could be more sophisticated, see
2688 * linux-kernel thread starting with
2689 * <73defb5e4bca04a6431392cc341112b1@localhost>.
2691 static void layout_symtab(struct module
*mod
, struct load_info
*info
)
2693 Elf_Shdr
*symsect
= info
->sechdrs
+ info
->index
.sym
;
2694 Elf_Shdr
*strsect
= info
->sechdrs
+ info
->index
.str
;
2696 unsigned int i
, nsrc
, ndst
, strtab_size
= 0;
2698 /* Put symbol section at end of init part of module. */
2699 symsect
->sh_flags
|= SHF_ALLOC
;
2700 symsect
->sh_entsize
= get_offset(mod
, &mod
->init_layout
.size
, symsect
,
2701 info
->index
.sym
) | INIT_OFFSET_MASK
;
2702 pr_debug("\t%s\n", info
->secstrings
+ symsect
->sh_name
);
2704 src
= (void *)info
->hdr
+ symsect
->sh_offset
;
2705 nsrc
= symsect
->sh_size
/ sizeof(*src
);
2707 /* Compute total space required for the core symbols' strtab. */
2708 for (ndst
= i
= 0; i
< nsrc
; i
++) {
2709 if (i
== 0 || is_livepatch_module(mod
) ||
2710 is_core_symbol(src
+i
, info
->sechdrs
, info
->hdr
->e_shnum
,
2711 info
->index
.pcpu
)) {
2712 strtab_size
+= strlen(&info
->strtab
[src
[i
].st_name
])+1;
2717 /* Append room for core symbols at end of core part. */
2718 info
->symoffs
= ALIGN(mod
->core_layout
.size
, symsect
->sh_addralign
?: 1);
2719 info
->stroffs
= mod
->core_layout
.size
= info
->symoffs
+ ndst
* sizeof(Elf_Sym
);
2720 mod
->core_layout
.size
+= strtab_size
;
2721 info
->core_typeoffs
= mod
->core_layout
.size
;
2722 mod
->core_layout
.size
+= ndst
* sizeof(char);
2723 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2725 /* Put string table section at end of init part of module. */
2726 strsect
->sh_flags
|= SHF_ALLOC
;
2727 strsect
->sh_entsize
= get_offset(mod
, &mod
->init_layout
.size
, strsect
,
2728 info
->index
.str
) | INIT_OFFSET_MASK
;
2729 pr_debug("\t%s\n", info
->secstrings
+ strsect
->sh_name
);
2731 /* We'll tack temporary mod_kallsyms on the end. */
2732 mod
->init_layout
.size
= ALIGN(mod
->init_layout
.size
,
2733 __alignof__(struct mod_kallsyms
));
2734 info
->mod_kallsyms_init_off
= mod
->init_layout
.size
;
2735 mod
->init_layout
.size
+= sizeof(struct mod_kallsyms
);
2736 info
->init_typeoffs
= mod
->init_layout
.size
;
2737 mod
->init_layout
.size
+= nsrc
* sizeof(char);
2738 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2742 * We use the full symtab and strtab which layout_symtab arranged to
2743 * be appended to the init section. Later we switch to the cut-down
2746 static void add_kallsyms(struct module
*mod
, const struct load_info
*info
)
2748 unsigned int i
, ndst
;
2752 Elf_Shdr
*symsec
= &info
->sechdrs
[info
->index
.sym
];
2754 /* Set up to point into init section. */
2755 mod
->kallsyms
= mod
->init_layout
.base
+ info
->mod_kallsyms_init_off
;
2757 mod
->kallsyms
->symtab
= (void *)symsec
->sh_addr
;
2758 mod
->kallsyms
->num_symtab
= symsec
->sh_size
/ sizeof(Elf_Sym
);
2759 /* Make sure we get permanent strtab: don't use info->strtab. */
2760 mod
->kallsyms
->strtab
= (void *)info
->sechdrs
[info
->index
.str
].sh_addr
;
2761 mod
->kallsyms
->typetab
= mod
->init_layout
.base
+ info
->init_typeoffs
;
2764 * Now populate the cut down core kallsyms for after init
2765 * and set types up while we still have access to sections.
2767 mod
->core_kallsyms
.symtab
= dst
= mod
->core_layout
.base
+ info
->symoffs
;
2768 mod
->core_kallsyms
.strtab
= s
= mod
->core_layout
.base
+ info
->stroffs
;
2769 mod
->core_kallsyms
.typetab
= mod
->core_layout
.base
+ info
->core_typeoffs
;
2770 src
= mod
->kallsyms
->symtab
;
2771 for (ndst
= i
= 0; i
< mod
->kallsyms
->num_symtab
; i
++) {
2772 mod
->kallsyms
->typetab
[i
] = elf_type(src
+ i
, info
);
2773 if (i
== 0 || is_livepatch_module(mod
) ||
2774 is_core_symbol(src
+i
, info
->sechdrs
, info
->hdr
->e_shnum
,
2775 info
->index
.pcpu
)) {
2776 mod
->core_kallsyms
.typetab
[ndst
] =
2777 mod
->kallsyms
->typetab
[i
];
2779 dst
[ndst
++].st_name
= s
- mod
->core_kallsyms
.strtab
;
2780 s
+= strlcpy(s
, &mod
->kallsyms
->strtab
[src
[i
].st_name
],
2784 mod
->core_kallsyms
.num_symtab
= ndst
;
2787 static inline void layout_symtab(struct module
*mod
, struct load_info
*info
)
2791 static void add_kallsyms(struct module
*mod
, const struct load_info
*info
)
2794 #endif /* CONFIG_KALLSYMS */
2796 static void dynamic_debug_setup(struct module
*mod
, struct _ddebug
*debug
, unsigned int num
)
2800 ddebug_add_module(debug
, num
, mod
->name
);
2803 static void dynamic_debug_remove(struct module
*mod
, struct _ddebug
*debug
)
2806 ddebug_remove_module(mod
->name
);
2809 void * __weak
module_alloc(unsigned long size
)
2811 return vmalloc_exec(size
);
2814 bool __weak
module_exit_section(const char *name
)
2816 return strstarts(name
, ".exit");
2819 #ifdef CONFIG_DEBUG_KMEMLEAK
2820 static void kmemleak_load_module(const struct module
*mod
,
2821 const struct load_info
*info
)
2825 /* only scan the sections containing data */
2826 kmemleak_scan_area(mod
, sizeof(struct module
), GFP_KERNEL
);
2828 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2829 /* Scan all writable sections that's not executable */
2830 if (!(info
->sechdrs
[i
].sh_flags
& SHF_ALLOC
) ||
2831 !(info
->sechdrs
[i
].sh_flags
& SHF_WRITE
) ||
2832 (info
->sechdrs
[i
].sh_flags
& SHF_EXECINSTR
))
2835 kmemleak_scan_area((void *)info
->sechdrs
[i
].sh_addr
,
2836 info
->sechdrs
[i
].sh_size
, GFP_KERNEL
);
2840 static inline void kmemleak_load_module(const struct module
*mod
,
2841 const struct load_info
*info
)
2846 #ifdef CONFIG_MODULE_SIG
2847 static int module_sig_check(struct load_info
*info
, int flags
)
2850 const unsigned long markerlen
= sizeof(MODULE_SIG_STRING
) - 1;
2852 const void *mod
= info
->hdr
;
2855 * Require flags == 0, as a module with version information
2856 * removed is no longer the module that was signed
2859 info
->len
> markerlen
&&
2860 memcmp(mod
+ info
->len
- markerlen
, MODULE_SIG_STRING
, markerlen
) == 0) {
2861 /* We truncate the module to discard the signature */
2862 info
->len
-= markerlen
;
2863 err
= mod_verify_sig(mod
, info
);
2868 info
->sig_ok
= true;
2871 /* We don't permit modules to be loaded into trusted kernels
2872 * without a valid signature on them, but if we're not
2873 * enforcing, certain errors are non-fatal.
2876 reason
= "Loading of unsigned module";
2879 reason
= "Loading of module with unsupported crypto";
2882 reason
= "Loading of module with unavailable key";
2884 if (is_module_sig_enforced()) {
2885 pr_notice("%s is rejected\n", reason
);
2886 return -EKEYREJECTED
;
2889 return security_locked_down(LOCKDOWN_MODULE_SIGNATURE
);
2891 /* All other errors are fatal, including nomem, unparseable
2892 * signatures and signature check failures - even if signatures
2899 #else /* !CONFIG_MODULE_SIG */
2900 static int module_sig_check(struct load_info
*info
, int flags
)
2904 #endif /* !CONFIG_MODULE_SIG */
2906 /* Sanity checks against invalid binaries, wrong arch, weird elf version. */
2907 static int elf_header_check(struct load_info
*info
)
2909 if (info
->len
< sizeof(*(info
->hdr
)))
2912 if (memcmp(info
->hdr
->e_ident
, ELFMAG
, SELFMAG
) != 0
2913 || info
->hdr
->e_type
!= ET_REL
2914 || !elf_check_arch(info
->hdr
)
2915 || info
->hdr
->e_shentsize
!= sizeof(Elf_Shdr
))
2918 if (info
->hdr
->e_shoff
>= info
->len
2919 || (info
->hdr
->e_shnum
* sizeof(Elf_Shdr
) >
2920 info
->len
- info
->hdr
->e_shoff
))
2926 #define COPY_CHUNK_SIZE (16*PAGE_SIZE)
2928 static int copy_chunked_from_user(void *dst
, const void __user
*usrc
, unsigned long len
)
2931 unsigned long n
= min(len
, COPY_CHUNK_SIZE
);
2933 if (copy_from_user(dst
, usrc
, n
) != 0)
2943 #ifdef CONFIG_LIVEPATCH
2944 static int check_modinfo_livepatch(struct module
*mod
, struct load_info
*info
)
2946 if (get_modinfo(info
, "livepatch")) {
2948 add_taint_module(mod
, TAINT_LIVEPATCH
, LOCKDEP_STILL_OK
);
2949 pr_notice_once("%s: tainting kernel with TAINT_LIVEPATCH\n",
2955 #else /* !CONFIG_LIVEPATCH */
2956 static int check_modinfo_livepatch(struct module
*mod
, struct load_info
*info
)
2958 if (get_modinfo(info
, "livepatch")) {
2959 pr_err("%s: module is marked as livepatch module, but livepatch support is disabled",
2966 #endif /* CONFIG_LIVEPATCH */
2968 static void check_modinfo_retpoline(struct module
*mod
, struct load_info
*info
)
2970 if (retpoline_module_ok(get_modinfo(info
, "retpoline")))
2973 pr_warn("%s: loading module not compiled with retpoline compiler.\n",
2977 /* Sets info->hdr and info->len. */
2978 static int copy_module_from_user(const void __user
*umod
, unsigned long len
,
2979 struct load_info
*info
)
2984 if (info
->len
< sizeof(*(info
->hdr
)))
2987 err
= security_kernel_load_data(LOADING_MODULE
);
2991 /* Suck in entire file: we'll want most of it. */
2992 info
->hdr
= __vmalloc(info
->len
,
2993 GFP_KERNEL
| __GFP_NOWARN
, PAGE_KERNEL
);
2997 if (copy_chunked_from_user(info
->hdr
, umod
, info
->len
) != 0) {
3005 static void free_copy(struct load_info
*info
)
3010 static int rewrite_section_headers(struct load_info
*info
, int flags
)
3014 /* This should always be true, but let's be sure. */
3015 info
->sechdrs
[0].sh_addr
= 0;
3017 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
3018 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
3019 if (shdr
->sh_type
!= SHT_NOBITS
3020 && info
->len
< shdr
->sh_offset
+ shdr
->sh_size
) {
3021 pr_err("Module len %lu truncated\n", info
->len
);
3025 /* Mark all sections sh_addr with their address in the
3027 shdr
->sh_addr
= (size_t)info
->hdr
+ shdr
->sh_offset
;
3029 #ifndef CONFIG_MODULE_UNLOAD
3030 /* Don't load .exit sections */
3031 if (module_exit_section(info
->secstrings
+shdr
->sh_name
))
3032 shdr
->sh_flags
&= ~(unsigned long)SHF_ALLOC
;
3036 /* Track but don't keep modinfo and version sections. */
3037 info
->sechdrs
[info
->index
.vers
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
3038 info
->sechdrs
[info
->index
.info
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
3044 * Set up our basic convenience variables (pointers to section headers,
3045 * search for module section index etc), and do some basic section
3048 * Set info->mod to the temporary copy of the module in info->hdr. The final one
3049 * will be allocated in move_module().
3051 static int setup_load_info(struct load_info
*info
, int flags
)
3055 /* Set up the convenience variables */
3056 info
->sechdrs
= (void *)info
->hdr
+ info
->hdr
->e_shoff
;
3057 info
->secstrings
= (void *)info
->hdr
3058 + info
->sechdrs
[info
->hdr
->e_shstrndx
].sh_offset
;
3060 /* Try to find a name early so we can log errors with a module name */
3061 info
->index
.info
= find_sec(info
, ".modinfo");
3062 if (info
->index
.info
)
3063 info
->name
= get_modinfo(info
, "name");
3065 /* Find internal symbols and strings. */
3066 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
3067 if (info
->sechdrs
[i
].sh_type
== SHT_SYMTAB
) {
3068 info
->index
.sym
= i
;
3069 info
->index
.str
= info
->sechdrs
[i
].sh_link
;
3070 info
->strtab
= (char *)info
->hdr
3071 + info
->sechdrs
[info
->index
.str
].sh_offset
;
3076 if (info
->index
.sym
== 0) {
3077 pr_warn("%s: module has no symbols (stripped?)\n",
3078 info
->name
?: "(missing .modinfo section or name field)");
3082 info
->index
.mod
= find_sec(info
, ".gnu.linkonce.this_module");
3083 if (!info
->index
.mod
) {
3084 pr_warn("%s: No module found in object\n",
3085 info
->name
?: "(missing .modinfo section or name field)");
3088 /* This is temporary: point mod into copy of data. */
3089 info
->mod
= (void *)info
->hdr
+ info
->sechdrs
[info
->index
.mod
].sh_offset
;
3092 * If we didn't load the .modinfo 'name' field earlier, fall back to
3093 * on-disk struct mod 'name' field.
3096 info
->name
= info
->mod
->name
;
3098 if (flags
& MODULE_INIT_IGNORE_MODVERSIONS
)
3099 info
->index
.vers
= 0; /* Pretend no __versions section! */
3101 info
->index
.vers
= find_sec(info
, "__versions");
3103 info
->index
.pcpu
= find_pcpusec(info
);
3108 static int check_modinfo(struct module
*mod
, struct load_info
*info
, int flags
)
3110 const char *modmagic
= get_modinfo(info
, "vermagic");
3113 if (flags
& MODULE_INIT_IGNORE_VERMAGIC
)
3116 /* This is allowed: modprobe --force will invalidate it. */
3118 err
= try_to_force_load(mod
, "bad vermagic");
3121 } else if (!same_magic(modmagic
, vermagic
, info
->index
.vers
)) {
3122 pr_err("%s: version magic '%s' should be '%s'\n",
3123 info
->name
, modmagic
, vermagic
);
3127 if (!get_modinfo(info
, "intree")) {
3128 if (!test_taint(TAINT_OOT_MODULE
))
3129 pr_warn("%s: loading out-of-tree module taints kernel.\n",
3131 add_taint_module(mod
, TAINT_OOT_MODULE
, LOCKDEP_STILL_OK
);
3134 check_modinfo_retpoline(mod
, info
);
3136 if (get_modinfo(info
, "staging")) {
3137 add_taint_module(mod
, TAINT_CRAP
, LOCKDEP_STILL_OK
);
3138 pr_warn("%s: module is from the staging directory, the quality "
3139 "is unknown, you have been warned.\n", mod
->name
);
3142 err
= check_modinfo_livepatch(mod
, info
);
3146 /* Set up license info based on the info section */
3147 set_license(mod
, get_modinfo(info
, "license"));
3152 static int find_module_sections(struct module
*mod
, struct load_info
*info
)
3154 mod
->kp
= section_objs(info
, "__param",
3155 sizeof(*mod
->kp
), &mod
->num_kp
);
3156 mod
->syms
= section_objs(info
, "__ksymtab",
3157 sizeof(*mod
->syms
), &mod
->num_syms
);
3158 mod
->crcs
= section_addr(info
, "__kcrctab");
3159 mod
->gpl_syms
= section_objs(info
, "__ksymtab_gpl",
3160 sizeof(*mod
->gpl_syms
),
3161 &mod
->num_gpl_syms
);
3162 mod
->gpl_crcs
= section_addr(info
, "__kcrctab_gpl");
3163 mod
->gpl_future_syms
= section_objs(info
,
3164 "__ksymtab_gpl_future",
3165 sizeof(*mod
->gpl_future_syms
),
3166 &mod
->num_gpl_future_syms
);
3167 mod
->gpl_future_crcs
= section_addr(info
, "__kcrctab_gpl_future");
3169 #ifdef CONFIG_UNUSED_SYMBOLS
3170 mod
->unused_syms
= section_objs(info
, "__ksymtab_unused",
3171 sizeof(*mod
->unused_syms
),
3172 &mod
->num_unused_syms
);
3173 mod
->unused_crcs
= section_addr(info
, "__kcrctab_unused");
3174 mod
->unused_gpl_syms
= section_objs(info
, "__ksymtab_unused_gpl",
3175 sizeof(*mod
->unused_gpl_syms
),
3176 &mod
->num_unused_gpl_syms
);
3177 mod
->unused_gpl_crcs
= section_addr(info
, "__kcrctab_unused_gpl");
3179 #ifdef CONFIG_CONSTRUCTORS
3180 mod
->ctors
= section_objs(info
, ".ctors",
3181 sizeof(*mod
->ctors
), &mod
->num_ctors
);
3183 mod
->ctors
= section_objs(info
, ".init_array",
3184 sizeof(*mod
->ctors
), &mod
->num_ctors
);
3185 else if (find_sec(info
, ".init_array")) {
3187 * This shouldn't happen with same compiler and binutils
3188 * building all parts of the module.
3190 pr_warn("%s: has both .ctors and .init_array.\n",
3196 #ifdef CONFIG_TRACEPOINTS
3197 mod
->tracepoints_ptrs
= section_objs(info
, "__tracepoints_ptrs",
3198 sizeof(*mod
->tracepoints_ptrs
),
3199 &mod
->num_tracepoints
);
3201 #ifdef CONFIG_TREE_SRCU
3202 mod
->srcu_struct_ptrs
= section_objs(info
, "___srcu_struct_ptrs",
3203 sizeof(*mod
->srcu_struct_ptrs
),
3204 &mod
->num_srcu_structs
);
3206 #ifdef CONFIG_BPF_EVENTS
3207 mod
->bpf_raw_events
= section_objs(info
, "__bpf_raw_tp_map",
3208 sizeof(*mod
->bpf_raw_events
),
3209 &mod
->num_bpf_raw_events
);
3211 #ifdef CONFIG_JUMP_LABEL
3212 mod
->jump_entries
= section_objs(info
, "__jump_table",
3213 sizeof(*mod
->jump_entries
),
3214 &mod
->num_jump_entries
);
3216 #ifdef CONFIG_EVENT_TRACING
3217 mod
->trace_events
= section_objs(info
, "_ftrace_events",
3218 sizeof(*mod
->trace_events
),
3219 &mod
->num_trace_events
);
3220 mod
->trace_evals
= section_objs(info
, "_ftrace_eval_map",
3221 sizeof(*mod
->trace_evals
),
3222 &mod
->num_trace_evals
);
3224 #ifdef CONFIG_TRACING
3225 mod
->trace_bprintk_fmt_start
= section_objs(info
, "__trace_printk_fmt",
3226 sizeof(*mod
->trace_bprintk_fmt_start
),
3227 &mod
->num_trace_bprintk_fmt
);
3229 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
3230 /* sechdrs[0].sh_size is always zero */
3231 mod
->ftrace_callsites
= section_objs(info
, "__mcount_loc",
3232 sizeof(*mod
->ftrace_callsites
),
3233 &mod
->num_ftrace_callsites
);
3235 #ifdef CONFIG_FUNCTION_ERROR_INJECTION
3236 mod
->ei_funcs
= section_objs(info
, "_error_injection_whitelist",
3237 sizeof(*mod
->ei_funcs
),
3238 &mod
->num_ei_funcs
);
3240 mod
->extable
= section_objs(info
, "__ex_table",
3241 sizeof(*mod
->extable
), &mod
->num_exentries
);
3243 if (section_addr(info
, "__obsparm"))
3244 pr_warn("%s: Ignoring obsolete parameters\n", mod
->name
);
3246 info
->debug
= section_objs(info
, "__verbose",
3247 sizeof(*info
->debug
), &info
->num_debug
);
3252 static int move_module(struct module
*mod
, struct load_info
*info
)
3257 /* Do the allocs. */
3258 ptr
= module_alloc(mod
->core_layout
.size
);
3260 * The pointer to this block is stored in the module structure
3261 * which is inside the block. Just mark it as not being a
3264 kmemleak_not_leak(ptr
);
3268 memset(ptr
, 0, mod
->core_layout
.size
);
3269 mod
->core_layout
.base
= ptr
;
3271 if (mod
->init_layout
.size
) {
3272 ptr
= module_alloc(mod
->init_layout
.size
);
3274 * The pointer to this block is stored in the module structure
3275 * which is inside the block. This block doesn't need to be
3276 * scanned as it contains data and code that will be freed
3277 * after the module is initialized.
3279 kmemleak_ignore(ptr
);
3281 module_memfree(mod
->core_layout
.base
);
3284 memset(ptr
, 0, mod
->init_layout
.size
);
3285 mod
->init_layout
.base
= ptr
;
3287 mod
->init_layout
.base
= NULL
;
3289 /* Transfer each section which specifies SHF_ALLOC */
3290 pr_debug("final section addresses:\n");
3291 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++) {
3293 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
3295 if (!(shdr
->sh_flags
& SHF_ALLOC
))
3298 if (shdr
->sh_entsize
& INIT_OFFSET_MASK
)
3299 dest
= mod
->init_layout
.base
3300 + (shdr
->sh_entsize
& ~INIT_OFFSET_MASK
);
3302 dest
= mod
->core_layout
.base
+ shdr
->sh_entsize
;
3304 if (shdr
->sh_type
!= SHT_NOBITS
)
3305 memcpy(dest
, (void *)shdr
->sh_addr
, shdr
->sh_size
);
3306 /* Update sh_addr to point to copy in image. */
3307 shdr
->sh_addr
= (unsigned long)dest
;
3308 pr_debug("\t0x%lx %s\n",
3309 (long)shdr
->sh_addr
, info
->secstrings
+ shdr
->sh_name
);
3315 static int check_module_license_and_versions(struct module
*mod
)
3317 int prev_taint
= test_taint(TAINT_PROPRIETARY_MODULE
);
3320 * ndiswrapper is under GPL by itself, but loads proprietary modules.
3321 * Don't use add_taint_module(), as it would prevent ndiswrapper from
3322 * using GPL-only symbols it needs.
3324 if (strcmp(mod
->name
, "ndiswrapper") == 0)
3325 add_taint(TAINT_PROPRIETARY_MODULE
, LOCKDEP_NOW_UNRELIABLE
);
3327 /* driverloader was caught wrongly pretending to be under GPL */
3328 if (strcmp(mod
->name
, "driverloader") == 0)
3329 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
3330 LOCKDEP_NOW_UNRELIABLE
);
3332 /* lve claims to be GPL but upstream won't provide source */
3333 if (strcmp(mod
->name
, "lve") == 0)
3334 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
3335 LOCKDEP_NOW_UNRELIABLE
);
3337 if (!prev_taint
&& test_taint(TAINT_PROPRIETARY_MODULE
))
3338 pr_warn("%s: module license taints kernel.\n", mod
->name
);
3340 #ifdef CONFIG_MODVERSIONS
3341 if ((mod
->num_syms
&& !mod
->crcs
)
3342 || (mod
->num_gpl_syms
&& !mod
->gpl_crcs
)
3343 || (mod
->num_gpl_future_syms
&& !mod
->gpl_future_crcs
)
3344 #ifdef CONFIG_UNUSED_SYMBOLS
3345 || (mod
->num_unused_syms
&& !mod
->unused_crcs
)
3346 || (mod
->num_unused_gpl_syms
&& !mod
->unused_gpl_crcs
)
3349 return try_to_force_load(mod
,
3350 "no versions for exported symbols");
3356 static void flush_module_icache(const struct module
*mod
)
3358 mm_segment_t old_fs
;
3360 /* flush the icache in correct context */
3365 * Flush the instruction cache, since we've played with text.
3366 * Do it before processing of module parameters, so the module
3367 * can provide parameter accessor functions of its own.
3369 if (mod
->init_layout
.base
)
3370 flush_icache_range((unsigned long)mod
->init_layout
.base
,
3371 (unsigned long)mod
->init_layout
.base
3372 + mod
->init_layout
.size
);
3373 flush_icache_range((unsigned long)mod
->core_layout
.base
,
3374 (unsigned long)mod
->core_layout
.base
+ mod
->core_layout
.size
);
3379 int __weak
module_frob_arch_sections(Elf_Ehdr
*hdr
,
3387 /* module_blacklist is a comma-separated list of module names */
3388 static char *module_blacklist
;
3389 static bool blacklisted(const char *module_name
)
3394 if (!module_blacklist
)
3397 for (p
= module_blacklist
; *p
; p
+= len
) {
3398 len
= strcspn(p
, ",");
3399 if (strlen(module_name
) == len
&& !memcmp(module_name
, p
, len
))
3406 core_param(module_blacklist
, module_blacklist
, charp
, 0400);
3408 static struct module
*layout_and_allocate(struct load_info
*info
, int flags
)
3414 err
= check_modinfo(info
->mod
, info
, flags
);
3416 return ERR_PTR(err
);
3418 /* Allow arches to frob section contents and sizes. */
3419 err
= module_frob_arch_sections(info
->hdr
, info
->sechdrs
,
3420 info
->secstrings
, info
->mod
);
3422 return ERR_PTR(err
);
3424 /* We will do a special allocation for per-cpu sections later. */
3425 info
->sechdrs
[info
->index
.pcpu
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
3428 * Mark ro_after_init section with SHF_RO_AFTER_INIT so that
3429 * layout_sections() can put it in the right place.
3430 * Note: ro_after_init sections also have SHF_{WRITE,ALLOC} set.
3432 ndx
= find_sec(info
, ".data..ro_after_init");
3434 info
->sechdrs
[ndx
].sh_flags
|= SHF_RO_AFTER_INIT
;
3436 * Mark the __jump_table section as ro_after_init as well: these data
3437 * structures are never modified, with the exception of entries that
3438 * refer to code in the __init section, which are annotated as such
3439 * at module load time.
3441 ndx
= find_sec(info
, "__jump_table");
3443 info
->sechdrs
[ndx
].sh_flags
|= SHF_RO_AFTER_INIT
;
3445 /* Determine total sizes, and put offsets in sh_entsize. For now
3446 this is done generically; there doesn't appear to be any
3447 special cases for the architectures. */
3448 layout_sections(info
->mod
, info
);
3449 layout_symtab(info
->mod
, info
);
3451 /* Allocate and move to the final place */
3452 err
= move_module(info
->mod
, info
);
3454 return ERR_PTR(err
);
3456 /* Module has been copied to its final place now: return it. */
3457 mod
= (void *)info
->sechdrs
[info
->index
.mod
].sh_addr
;
3458 kmemleak_load_module(mod
, info
);
3462 /* mod is no longer valid after this! */
3463 static void module_deallocate(struct module
*mod
, struct load_info
*info
)
3465 percpu_modfree(mod
);
3466 module_arch_freeing_init(mod
);
3467 module_memfree(mod
->init_layout
.base
);
3468 module_memfree(mod
->core_layout
.base
);
3471 int __weak
module_finalize(const Elf_Ehdr
*hdr
,
3472 const Elf_Shdr
*sechdrs
,
3478 static int post_relocation(struct module
*mod
, const struct load_info
*info
)
3480 /* Sort exception table now relocations are done. */
3481 sort_extable(mod
->extable
, mod
->extable
+ mod
->num_exentries
);
3483 /* Copy relocated percpu area over. */
3484 percpu_modcopy(mod
, (void *)info
->sechdrs
[info
->index
.pcpu
].sh_addr
,
3485 info
->sechdrs
[info
->index
.pcpu
].sh_size
);
3487 /* Setup kallsyms-specific fields. */
3488 add_kallsyms(mod
, info
);
3490 /* Arch-specific module finalizing. */
3491 return module_finalize(info
->hdr
, info
->sechdrs
, mod
);
3494 /* Is this module of this name done loading? No locks held. */
3495 static bool finished_loading(const char *name
)
3501 * The module_mutex should not be a heavily contended lock;
3502 * if we get the occasional sleep here, we'll go an extra iteration
3503 * in the wait_event_interruptible(), which is harmless.
3505 sched_annotate_sleep();
3506 mutex_lock(&module_mutex
);
3507 mod
= find_module_all(name
, strlen(name
), true);
3508 ret
= !mod
|| mod
->state
== MODULE_STATE_LIVE
;
3509 mutex_unlock(&module_mutex
);
3514 /* Call module constructors. */
3515 static void do_mod_ctors(struct module
*mod
)
3517 #ifdef CONFIG_CONSTRUCTORS
3520 for (i
= 0; i
< mod
->num_ctors
; i
++)
3525 /* For freeing module_init on success, in case kallsyms traversing */
3526 struct mod_initfree
{
3527 struct llist_node node
;
3531 static void do_free_init(struct work_struct
*w
)
3533 struct llist_node
*pos
, *n
, *list
;
3534 struct mod_initfree
*initfree
;
3536 list
= llist_del_all(&init_free_list
);
3540 llist_for_each_safe(pos
, n
, list
) {
3541 initfree
= container_of(pos
, struct mod_initfree
, node
);
3542 module_memfree(initfree
->module_init
);
3547 static int __init
modules_wq_init(void)
3549 INIT_WORK(&init_free_wq
, do_free_init
);
3550 init_llist_head(&init_free_list
);
3553 module_init(modules_wq_init
);
3556 * This is where the real work happens.
3558 * Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb
3559 * helper command 'lx-symbols'.
3561 static noinline
int do_init_module(struct module
*mod
)
3564 struct mod_initfree
*freeinit
;
3566 freeinit
= kmalloc(sizeof(*freeinit
), GFP_KERNEL
);
3571 freeinit
->module_init
= mod
->init_layout
.base
;
3574 * We want to find out whether @mod uses async during init. Clear
3575 * PF_USED_ASYNC. async_schedule*() will set it.
3577 current
->flags
&= ~PF_USED_ASYNC
;
3580 /* Start the module */
3581 if (mod
->init
!= NULL
)
3582 ret
= do_one_initcall(mod
->init
);
3584 goto fail_free_freeinit
;
3587 pr_warn("%s: '%s'->init suspiciously returned %d, it should "
3588 "follow 0/-E convention\n"
3589 "%s: loading module anyway...\n",
3590 __func__
, mod
->name
, ret
, __func__
);
3594 /* Now it's a first class citizen! */
3595 mod
->state
= MODULE_STATE_LIVE
;
3596 blocking_notifier_call_chain(&module_notify_list
,
3597 MODULE_STATE_LIVE
, mod
);
3600 * We need to finish all async code before the module init sequence
3601 * is done. This has potential to deadlock. For example, a newly
3602 * detected block device can trigger request_module() of the
3603 * default iosched from async probing task. Once userland helper
3604 * reaches here, async_synchronize_full() will wait on the async
3605 * task waiting on request_module() and deadlock.
3607 * This deadlock is avoided by perfomring async_synchronize_full()
3608 * iff module init queued any async jobs. This isn't a full
3609 * solution as it will deadlock the same if module loading from
3610 * async jobs nests more than once; however, due to the various
3611 * constraints, this hack seems to be the best option for now.
3612 * Please refer to the following thread for details.
3614 * http://thread.gmane.org/gmane.linux.kernel/1420814
3616 if (!mod
->async_probe_requested
&& (current
->flags
& PF_USED_ASYNC
))
3617 async_synchronize_full();
3619 ftrace_free_mem(mod
, mod
->init_layout
.base
, mod
->init_layout
.base
+
3620 mod
->init_layout
.size
);
3621 mutex_lock(&module_mutex
);
3622 /* Drop initial reference. */
3624 trim_init_extable(mod
);
3625 #ifdef CONFIG_KALLSYMS
3626 /* Switch to core kallsyms now init is done: kallsyms may be walking! */
3627 rcu_assign_pointer(mod
->kallsyms
, &mod
->core_kallsyms
);
3629 module_enable_ro(mod
, true);
3630 mod_tree_remove_init(mod
);
3631 module_arch_freeing_init(mod
);
3632 mod
->init_layout
.base
= NULL
;
3633 mod
->init_layout
.size
= 0;
3634 mod
->init_layout
.ro_size
= 0;
3635 mod
->init_layout
.ro_after_init_size
= 0;
3636 mod
->init_layout
.text_size
= 0;
3638 * We want to free module_init, but be aware that kallsyms may be
3639 * walking this with preempt disabled. In all the failure paths, we
3640 * call synchronize_rcu(), but we don't want to slow down the success
3641 * path. module_memfree() cannot be called in an interrupt, so do the
3642 * work and call synchronize_rcu() in a work queue.
3644 * Note that module_alloc() on most architectures creates W+X page
3645 * mappings which won't be cleaned up until do_free_init() runs. Any
3646 * code such as mark_rodata_ro() which depends on those mappings to
3647 * be cleaned up needs to sync with the queued work - ie
3650 if (llist_add(&freeinit
->node
, &init_free_list
))
3651 schedule_work(&init_free_wq
);
3653 mutex_unlock(&module_mutex
);
3654 wake_up_all(&module_wq
);
3661 /* Try to protect us from buggy refcounters. */
3662 mod
->state
= MODULE_STATE_GOING
;
3665 blocking_notifier_call_chain(&module_notify_list
,
3666 MODULE_STATE_GOING
, mod
);
3667 klp_module_going(mod
);
3668 ftrace_release_mod(mod
);
3670 wake_up_all(&module_wq
);
3674 static int may_init_module(void)
3676 if (!capable(CAP_SYS_MODULE
) || modules_disabled
)
3683 * We try to place it in the list now to make sure it's unique before
3684 * we dedicate too many resources. In particular, temporary percpu
3685 * memory exhaustion.
3687 static int add_unformed_module(struct module
*mod
)
3692 mod
->state
= MODULE_STATE_UNFORMED
;
3695 mutex_lock(&module_mutex
);
3696 old
= find_module_all(mod
->name
, strlen(mod
->name
), true);
3698 if (old
->state
!= MODULE_STATE_LIVE
) {
3699 /* Wait in case it fails to load. */
3700 mutex_unlock(&module_mutex
);
3701 err
= wait_event_interruptible(module_wq
,
3702 finished_loading(mod
->name
));
3710 mod_update_bounds(mod
);
3711 list_add_rcu(&mod
->list
, &modules
);
3712 mod_tree_insert(mod
);
3716 mutex_unlock(&module_mutex
);
3721 static int complete_formation(struct module
*mod
, struct load_info
*info
)
3725 mutex_lock(&module_mutex
);
3727 /* Find duplicate symbols (must be called under lock). */
3728 err
= verify_exported_symbols(mod
);
3732 /* This relies on module_mutex for list integrity. */
3733 module_bug_finalize(info
->hdr
, info
->sechdrs
, mod
);
3735 module_enable_ro(mod
, false);
3736 module_enable_nx(mod
);
3737 module_enable_x(mod
);
3739 /* Mark state as coming so strong_try_module_get() ignores us,
3740 * but kallsyms etc. can see us. */
3741 mod
->state
= MODULE_STATE_COMING
;
3742 mutex_unlock(&module_mutex
);
3747 mutex_unlock(&module_mutex
);
3751 static int prepare_coming_module(struct module
*mod
)
3755 ftrace_module_enable(mod
);
3756 err
= klp_module_coming(mod
);
3760 blocking_notifier_call_chain(&module_notify_list
,
3761 MODULE_STATE_COMING
, mod
);
3765 static int unknown_module_param_cb(char *param
, char *val
, const char *modname
,
3768 struct module
*mod
= arg
;
3771 if (strcmp(param
, "async_probe") == 0) {
3772 mod
->async_probe_requested
= true;
3776 /* Check for magic 'dyndbg' arg */
3777 ret
= ddebug_dyndbg_module_param_cb(param
, val
, modname
);
3779 pr_warn("%s: unknown parameter '%s' ignored\n", modname
, param
);
3783 /* Allocate and load the module: note that size of section 0 is always
3784 zero, and we rely on this for optional sections. */
3785 static int load_module(struct load_info
*info
, const char __user
*uargs
,
3792 err
= elf_header_check(info
);
3796 err
= setup_load_info(info
, flags
);
3800 if (blacklisted(info
->name
)) {
3805 err
= module_sig_check(info
, flags
);
3809 err
= rewrite_section_headers(info
, flags
);
3813 /* Check module struct version now, before we try to use module. */
3814 if (!check_modstruct_version(info
, info
->mod
)) {
3819 /* Figure out module layout, and allocate all the memory. */
3820 mod
= layout_and_allocate(info
, flags
);
3826 audit_log_kern_module(mod
->name
);
3828 /* Reserve our place in the list. */
3829 err
= add_unformed_module(mod
);
3833 #ifdef CONFIG_MODULE_SIG
3834 mod
->sig_ok
= info
->sig_ok
;
3836 pr_notice_once("%s: module verification failed: signature "
3837 "and/or required key missing - tainting "
3838 "kernel\n", mod
->name
);
3839 add_taint_module(mod
, TAINT_UNSIGNED_MODULE
, LOCKDEP_STILL_OK
);
3843 /* To avoid stressing percpu allocator, do this once we're unique. */
3844 err
= percpu_modalloc(mod
, info
);
3848 /* Now module is in final location, initialize linked lists, etc. */
3849 err
= module_unload_init(mod
);
3853 init_param_lock(mod
);
3855 /* Now we've got everything in the final locations, we can
3856 * find optional sections. */
3857 err
= find_module_sections(mod
, info
);
3861 err
= check_module_license_and_versions(mod
);
3865 /* Set up MODINFO_ATTR fields */
3866 setup_modinfo(mod
, info
);
3868 /* Fix up syms, so that st_value is a pointer to location. */
3869 err
= simplify_symbols(mod
, info
);
3873 err
= apply_relocations(mod
, info
);
3877 err
= post_relocation(mod
, info
);
3881 flush_module_icache(mod
);
3883 /* Now copy in args */
3884 mod
->args
= strndup_user(uargs
, ~0UL >> 1);
3885 if (IS_ERR(mod
->args
)) {
3886 err
= PTR_ERR(mod
->args
);
3887 goto free_arch_cleanup
;
3890 dynamic_debug_setup(mod
, info
->debug
, info
->num_debug
);
3892 /* Ftrace init must be called in the MODULE_STATE_UNFORMED state */
3893 ftrace_module_init(mod
);
3895 /* Finally it's fully formed, ready to start executing. */
3896 err
= complete_formation(mod
, info
);
3898 goto ddebug_cleanup
;
3900 err
= prepare_coming_module(mod
);
3904 /* Module is ready to execute: parsing args may do that. */
3905 after_dashes
= parse_args(mod
->name
, mod
->args
, mod
->kp
, mod
->num_kp
,
3907 unknown_module_param_cb
);
3908 if (IS_ERR(after_dashes
)) {
3909 err
= PTR_ERR(after_dashes
);
3910 goto coming_cleanup
;
3911 } else if (after_dashes
) {
3912 pr_warn("%s: parameters '%s' after `--' ignored\n",
3913 mod
->name
, after_dashes
);
3916 /* Link in to sysfs. */
3917 err
= mod_sysfs_setup(mod
, info
, mod
->kp
, mod
->num_kp
);
3919 goto coming_cleanup
;
3921 if (is_livepatch_module(mod
)) {
3922 err
= copy_module_elf(mod
, info
);
3927 /* Get rid of temporary copy. */
3931 trace_module_load(mod
);
3933 return do_init_module(mod
);
3936 mod_sysfs_teardown(mod
);
3938 mod
->state
= MODULE_STATE_GOING
;
3939 destroy_params(mod
->kp
, mod
->num_kp
);
3940 blocking_notifier_call_chain(&module_notify_list
,
3941 MODULE_STATE_GOING
, mod
);
3942 klp_module_going(mod
);
3944 /* module_bug_cleanup needs module_mutex protection */
3945 mutex_lock(&module_mutex
);
3946 module_bug_cleanup(mod
);
3947 mutex_unlock(&module_mutex
);
3950 ftrace_release_mod(mod
);
3951 dynamic_debug_remove(mod
, info
->debug
);
3955 module_arch_cleanup(mod
);
3959 module_unload_free(mod
);
3961 mutex_lock(&module_mutex
);
3962 /* Unlink carefully: kallsyms could be walking list. */
3963 list_del_rcu(&mod
->list
);
3964 mod_tree_remove(mod
);
3965 wake_up_all(&module_wq
);
3966 /* Wait for RCU-sched synchronizing before releasing mod->list. */
3968 mutex_unlock(&module_mutex
);
3970 /* Free lock-classes; relies on the preceding sync_rcu() */
3971 lockdep_free_key_range(mod
->core_layout
.base
, mod
->core_layout
.size
);
3973 module_deallocate(mod
, info
);
3979 SYSCALL_DEFINE3(init_module
, void __user
*, umod
,
3980 unsigned long, len
, const char __user
*, uargs
)
3983 struct load_info info
= { };
3985 err
= may_init_module();
3989 pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
3992 err
= copy_module_from_user(umod
, len
, &info
);
3996 return load_module(&info
, uargs
, 0);
3999 SYSCALL_DEFINE3(finit_module
, int, fd
, const char __user
*, uargs
, int, flags
)
4001 struct load_info info
= { };
4006 err
= may_init_module();
4010 pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd
, uargs
, flags
);
4012 if (flags
& ~(MODULE_INIT_IGNORE_MODVERSIONS
4013 |MODULE_INIT_IGNORE_VERMAGIC
))
4016 err
= kernel_read_file_from_fd(fd
, &hdr
, &size
, INT_MAX
,
4023 return load_module(&info
, uargs
, flags
);
4026 static inline int within(unsigned long addr
, void *start
, unsigned long size
)
4028 return ((void *)addr
>= start
&& (void *)addr
< start
+ size
);
4031 #ifdef CONFIG_KALLSYMS
4033 * This ignores the intensely annoying "mapping symbols" found
4034 * in ARM ELF files: $a, $t and $d.
4036 static inline int is_arm_mapping_symbol(const char *str
)
4038 if (str
[0] == '.' && str
[1] == 'L')
4040 return str
[0] == '$' && strchr("axtd", str
[1])
4041 && (str
[2] == '\0' || str
[2] == '.');
4044 static const char *kallsyms_symbol_name(struct mod_kallsyms
*kallsyms
, unsigned int symnum
)
4046 return kallsyms
->strtab
+ kallsyms
->symtab
[symnum
].st_name
;
4050 * Given a module and address, find the corresponding symbol and return its name
4051 * while providing its size and offset if needed.
4053 static const char *find_kallsyms_symbol(struct module
*mod
,
4055 unsigned long *size
,
4056 unsigned long *offset
)
4058 unsigned int i
, best
= 0;
4059 unsigned long nextval
, bestval
;
4060 struct mod_kallsyms
*kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
4062 /* At worse, next value is at end of module */
4063 if (within_module_init(addr
, mod
))
4064 nextval
= (unsigned long)mod
->init_layout
.base
+mod
->init_layout
.text_size
;
4066 nextval
= (unsigned long)mod
->core_layout
.base
+mod
->core_layout
.text_size
;
4068 bestval
= kallsyms_symbol_value(&kallsyms
->symtab
[best
]);
4070 /* Scan for closest preceding symbol, and next symbol. (ELF
4071 starts real symbols at 1). */
4072 for (i
= 1; i
< kallsyms
->num_symtab
; i
++) {
4073 const Elf_Sym
*sym
= &kallsyms
->symtab
[i
];
4074 unsigned long thisval
= kallsyms_symbol_value(sym
);
4076 if (sym
->st_shndx
== SHN_UNDEF
)
4079 /* We ignore unnamed symbols: they're uninformative
4080 * and inserted at a whim. */
4081 if (*kallsyms_symbol_name(kallsyms
, i
) == '\0'
4082 || is_arm_mapping_symbol(kallsyms_symbol_name(kallsyms
, i
)))
4085 if (thisval
<= addr
&& thisval
> bestval
) {
4089 if (thisval
> addr
&& thisval
< nextval
)
4097 *size
= nextval
- bestval
;
4099 *offset
= addr
- bestval
;
4101 return kallsyms_symbol_name(kallsyms
, best
);
4104 void * __weak
dereference_module_function_descriptor(struct module
*mod
,
4110 /* For kallsyms to ask for address resolution. NULL means not found. Careful
4111 * not to lock to avoid deadlock on oopses, simply disable preemption. */
4112 const char *module_address_lookup(unsigned long addr
,
4113 unsigned long *size
,
4114 unsigned long *offset
,
4118 const char *ret
= NULL
;
4122 mod
= __module_address(addr
);
4125 *modname
= mod
->name
;
4127 ret
= find_kallsyms_symbol(mod
, addr
, size
, offset
);
4129 /* Make a copy in here where it's safe */
4131 strncpy(namebuf
, ret
, KSYM_NAME_LEN
- 1);
4139 int lookup_module_symbol_name(unsigned long addr
, char *symname
)
4144 list_for_each_entry_rcu(mod
, &modules
, list
) {
4145 if (mod
->state
== MODULE_STATE_UNFORMED
)
4147 if (within_module(addr
, mod
)) {
4150 sym
= find_kallsyms_symbol(mod
, addr
, NULL
, NULL
);
4154 strlcpy(symname
, sym
, KSYM_NAME_LEN
);
4164 int lookup_module_symbol_attrs(unsigned long addr
, unsigned long *size
,
4165 unsigned long *offset
, char *modname
, char *name
)
4170 list_for_each_entry_rcu(mod
, &modules
, list
) {
4171 if (mod
->state
== MODULE_STATE_UNFORMED
)
4173 if (within_module(addr
, mod
)) {
4176 sym
= find_kallsyms_symbol(mod
, addr
, size
, offset
);
4180 strlcpy(modname
, mod
->name
, MODULE_NAME_LEN
);
4182 strlcpy(name
, sym
, KSYM_NAME_LEN
);
4192 int module_get_kallsym(unsigned int symnum
, unsigned long *value
, char *type
,
4193 char *name
, char *module_name
, int *exported
)
4198 list_for_each_entry_rcu(mod
, &modules
, list
) {
4199 struct mod_kallsyms
*kallsyms
;
4201 if (mod
->state
== MODULE_STATE_UNFORMED
)
4203 kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
4204 if (symnum
< kallsyms
->num_symtab
) {
4205 const Elf_Sym
*sym
= &kallsyms
->symtab
[symnum
];
4207 *value
= kallsyms_symbol_value(sym
);
4208 *type
= kallsyms
->typetab
[symnum
];
4209 strlcpy(name
, kallsyms_symbol_name(kallsyms
, symnum
), KSYM_NAME_LEN
);
4210 strlcpy(module_name
, mod
->name
, MODULE_NAME_LEN
);
4211 *exported
= is_exported(name
, *value
, mod
);
4215 symnum
-= kallsyms
->num_symtab
;
4221 /* Given a module and name of symbol, find and return the symbol's value */
4222 static unsigned long find_kallsyms_symbol_value(struct module
*mod
, const char *name
)
4225 struct mod_kallsyms
*kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
4227 for (i
= 0; i
< kallsyms
->num_symtab
; i
++) {
4228 const Elf_Sym
*sym
= &kallsyms
->symtab
[i
];
4230 if (strcmp(name
, kallsyms_symbol_name(kallsyms
, i
)) == 0 &&
4231 sym
->st_shndx
!= SHN_UNDEF
)
4232 return kallsyms_symbol_value(sym
);
4237 /* Look for this name: can be of form module:name. */
4238 unsigned long module_kallsyms_lookup_name(const char *name
)
4242 unsigned long ret
= 0;
4244 /* Don't lock: we're in enough trouble already. */
4246 if ((colon
= strnchr(name
, MODULE_NAME_LEN
, ':')) != NULL
) {
4247 if ((mod
= find_module_all(name
, colon
- name
, false)) != NULL
)
4248 ret
= find_kallsyms_symbol_value(mod
, colon
+1);
4250 list_for_each_entry_rcu(mod
, &modules
, list
) {
4251 if (mod
->state
== MODULE_STATE_UNFORMED
)
4253 if ((ret
= find_kallsyms_symbol_value(mod
, name
)) != 0)
4261 int module_kallsyms_on_each_symbol(int (*fn
)(void *, const char *,
4262 struct module
*, unsigned long),
4269 module_assert_mutex();
4271 list_for_each_entry(mod
, &modules
, list
) {
4272 /* We hold module_mutex: no need for rcu_dereference_sched */
4273 struct mod_kallsyms
*kallsyms
= mod
->kallsyms
;
4275 if (mod
->state
== MODULE_STATE_UNFORMED
)
4277 for (i
= 0; i
< kallsyms
->num_symtab
; i
++) {
4278 const Elf_Sym
*sym
= &kallsyms
->symtab
[i
];
4280 if (sym
->st_shndx
== SHN_UNDEF
)
4283 ret
= fn(data
, kallsyms_symbol_name(kallsyms
, i
),
4284 mod
, kallsyms_symbol_value(sym
));
4291 #endif /* CONFIG_KALLSYMS */
4293 /* Maximum number of characters written by module_flags() */
4294 #define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4)
4296 /* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */
4297 static char *module_flags(struct module
*mod
, char *buf
)
4301 BUG_ON(mod
->state
== MODULE_STATE_UNFORMED
);
4303 mod
->state
== MODULE_STATE_GOING
||
4304 mod
->state
== MODULE_STATE_COMING
) {
4306 bx
+= module_flags_taint(mod
, buf
+ bx
);
4307 /* Show a - for module-is-being-unloaded */
4308 if (mod
->state
== MODULE_STATE_GOING
)
4310 /* Show a + for module-is-being-loaded */
4311 if (mod
->state
== MODULE_STATE_COMING
)
4320 #ifdef CONFIG_PROC_FS
4321 /* Called by the /proc file system to return a list of modules. */
4322 static void *m_start(struct seq_file
*m
, loff_t
*pos
)
4324 mutex_lock(&module_mutex
);
4325 return seq_list_start(&modules
, *pos
);
4328 static void *m_next(struct seq_file
*m
, void *p
, loff_t
*pos
)
4330 return seq_list_next(p
, &modules
, pos
);
4333 static void m_stop(struct seq_file
*m
, void *p
)
4335 mutex_unlock(&module_mutex
);
4338 static int m_show(struct seq_file
*m
, void *p
)
4340 struct module
*mod
= list_entry(p
, struct module
, list
);
4341 char buf
[MODULE_FLAGS_BUF_SIZE
];
4344 /* We always ignore unformed modules. */
4345 if (mod
->state
== MODULE_STATE_UNFORMED
)
4348 seq_printf(m
, "%s %u",
4349 mod
->name
, mod
->init_layout
.size
+ mod
->core_layout
.size
);
4350 print_unload_info(m
, mod
);
4352 /* Informative for users. */
4353 seq_printf(m
, " %s",
4354 mod
->state
== MODULE_STATE_GOING
? "Unloading" :
4355 mod
->state
== MODULE_STATE_COMING
? "Loading" :
4357 /* Used by oprofile and other similar tools. */
4358 value
= m
->private ? NULL
: mod
->core_layout
.base
;
4359 seq_printf(m
, " 0x%px", value
);
4363 seq_printf(m
, " %s", module_flags(mod
, buf
));
4369 /* Format: modulename size refcount deps address
4371 Where refcount is a number or -, and deps is a comma-separated list
4374 static const struct seq_operations modules_op
= {
4382 * This also sets the "private" pointer to non-NULL if the
4383 * kernel pointers should be hidden (so you can just test
4384 * "m->private" to see if you should keep the values private).
4386 * We use the same logic as for /proc/kallsyms.
4388 static int modules_open(struct inode
*inode
, struct file
*file
)
4390 int err
= seq_open(file
, &modules_op
);
4393 struct seq_file
*m
= file
->private_data
;
4394 m
->private = kallsyms_show_value() ? NULL
: (void *)8ul;
4400 static const struct file_operations proc_modules_operations
= {
4401 .open
= modules_open
,
4403 .llseek
= seq_lseek
,
4404 .release
= seq_release
,
4407 static int __init
proc_modules_init(void)
4409 proc_create("modules", 0, NULL
, &proc_modules_operations
);
4412 module_init(proc_modules_init
);
4415 /* Given an address, look for it in the module exception tables. */
4416 const struct exception_table_entry
*search_module_extables(unsigned long addr
)
4418 const struct exception_table_entry
*e
= NULL
;
4422 mod
= __module_address(addr
);
4426 if (!mod
->num_exentries
)
4429 e
= search_extable(mod
->extable
,
4436 * Now, if we found one, we are running inside it now, hence
4437 * we cannot unload the module, hence no refcnt needed.
4443 * is_module_address - is this address inside a module?
4444 * @addr: the address to check.
4446 * See is_module_text_address() if you simply want to see if the address
4447 * is code (not data).
4449 bool is_module_address(unsigned long addr
)
4454 ret
= __module_address(addr
) != NULL
;
4461 * __module_address - get the module which contains an address.
4462 * @addr: the address.
4464 * Must be called with preempt disabled or module mutex held so that
4465 * module doesn't get freed during this.
4467 struct module
*__module_address(unsigned long addr
)
4471 if (addr
< module_addr_min
|| addr
> module_addr_max
)
4474 module_assert_mutex_or_preempt();
4476 mod
= mod_find(addr
);
4478 BUG_ON(!within_module(addr
, mod
));
4479 if (mod
->state
== MODULE_STATE_UNFORMED
)
4484 EXPORT_SYMBOL_GPL(__module_address
);
4487 * is_module_text_address - is this address inside module code?
4488 * @addr: the address to check.
4490 * See is_module_address() if you simply want to see if the address is
4491 * anywhere in a module. See kernel_text_address() for testing if an
4492 * address corresponds to kernel or module code.
4494 bool is_module_text_address(unsigned long addr
)
4499 ret
= __module_text_address(addr
) != NULL
;
4506 * __module_text_address - get the module whose code contains an address.
4507 * @addr: the address.
4509 * Must be called with preempt disabled or module mutex held so that
4510 * module doesn't get freed during this.
4512 struct module
*__module_text_address(unsigned long addr
)
4514 struct module
*mod
= __module_address(addr
);
4516 /* Make sure it's within the text section. */
4517 if (!within(addr
, mod
->init_layout
.base
, mod
->init_layout
.text_size
)
4518 && !within(addr
, mod
->core_layout
.base
, mod
->core_layout
.text_size
))
4523 EXPORT_SYMBOL_GPL(__module_text_address
);
4525 /* Don't grab lock, we're oopsing. */
4526 void print_modules(void)
4529 char buf
[MODULE_FLAGS_BUF_SIZE
];
4531 printk(KERN_DEFAULT
"Modules linked in:");
4532 /* Most callers should already have preempt disabled, but make sure */
4534 list_for_each_entry_rcu(mod
, &modules
, list
) {
4535 if (mod
->state
== MODULE_STATE_UNFORMED
)
4537 pr_cont(" %s%s", mod
->name
, module_flags(mod
, buf
));
4540 if (last_unloaded_module
[0])
4541 pr_cont(" [last unloaded: %s]", last_unloaded_module
);
4545 #ifdef CONFIG_MODVERSIONS
4546 /* Generate the signature for all relevant module structures here.
4547 * If these change, we don't want to try to parse the module. */
4548 void module_layout(struct module
*mod
,
4549 struct modversion_info
*ver
,
4550 struct kernel_param
*kp
,
4551 struct kernel_symbol
*ks
,
4552 struct tracepoint
* const *tp
)
4555 EXPORT_SYMBOL(module_layout
);