1 // SPDX-License-Identifier: GPL-2.0-or-later
3 Copyright (C) 2002 Richard Henderson
4 Copyright (C) 2001 Rusty Russell, 2002, 2010 Rusty Russell IBM.
8 #define INCLUDE_VERMAGIC
10 #include <linux/export.h>
11 #include <linux/extable.h>
12 #include <linux/moduleloader.h>
13 #include <linux/module_signature.h>
14 #include <linux/trace_events.h>
15 #include <linux/init.h>
16 #include <linux/kallsyms.h>
17 #include <linux/file.h>
19 #include <linux/sysfs.h>
20 #include <linux/kernel.h>
21 #include <linux/kernel_read_file.h>
22 #include <linux/slab.h>
23 #include <linux/vmalloc.h>
24 #include <linux/elf.h>
25 #include <linux/proc_fs.h>
26 #include <linux/security.h>
27 #include <linux/seq_file.h>
28 #include <linux/syscalls.h>
29 #include <linux/fcntl.h>
30 #include <linux/rcupdate.h>
31 #include <linux/capability.h>
32 #include <linux/cpu.h>
33 #include <linux/moduleparam.h>
34 #include <linux/errno.h>
35 #include <linux/err.h>
36 #include <linux/vermagic.h>
37 #include <linux/notifier.h>
38 #include <linux/sched.h>
39 #include <linux/device.h>
40 #include <linux/string.h>
41 #include <linux/mutex.h>
42 #include <linux/rculist.h>
43 #include <linux/uaccess.h>
44 #include <asm/cacheflush.h>
45 #include <linux/set_memory.h>
46 #include <asm/mmu_context.h>
47 #include <linux/license.h>
48 #include <asm/sections.h>
49 #include <linux/tracepoint.h>
50 #include <linux/ftrace.h>
51 #include <linux/livepatch.h>
52 #include <linux/async.h>
53 #include <linux/percpu.h>
54 #include <linux/kmemleak.h>
55 #include <linux/jump_label.h>
56 #include <linux/pfn.h>
57 #include <linux/bsearch.h>
58 #include <linux/dynamic_debug.h>
59 #include <linux/audit.h>
60 #include <uapi/linux/module.h>
61 #include "module-internal.h"
63 #define CREATE_TRACE_POINTS
64 #include <trace/events/module.h>
66 #ifndef ARCH_SHF_SMALL
67 #define ARCH_SHF_SMALL 0
71 * Modules' sections will be aligned on page boundaries
72 * to ensure complete separation of code and data, but
73 * only when CONFIG_ARCH_HAS_STRICT_MODULE_RWX=y
75 #ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX
76 # define debug_align(X) ALIGN(X, PAGE_SIZE)
78 # define debug_align(X) (X)
81 /* If this is set, the section belongs in the init part of the module */
82 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
86 * 1) List of modules (also safely readable with preempt_disable),
87 * 2) module_use links,
88 * 3) module_addr_min/module_addr_max.
89 * (delete and add uses RCU list operations). */
90 DEFINE_MUTEX(module_mutex
);
91 EXPORT_SYMBOL_GPL(module_mutex
);
92 static LIST_HEAD(modules
);
94 /* Work queue for freeing init sections in success case */
95 static void do_free_init(struct work_struct
*w
);
96 static DECLARE_WORK(init_free_wq
, do_free_init
);
97 static LLIST_HEAD(init_free_list
);
99 #ifdef CONFIG_MODULES_TREE_LOOKUP
102 * Use a latched RB-tree for __module_address(); this allows us to use
103 * RCU-sched lookups of the address from any context.
105 * This is conditional on PERF_EVENTS || TRACING because those can really hit
106 * __module_address() hard by doing a lot of stack unwinding; potentially from
110 static __always_inline
unsigned long __mod_tree_val(struct latch_tree_node
*n
)
112 struct module_layout
*layout
= container_of(n
, struct module_layout
, mtn
.node
);
114 return (unsigned long)layout
->base
;
117 static __always_inline
unsigned long __mod_tree_size(struct latch_tree_node
*n
)
119 struct module_layout
*layout
= container_of(n
, struct module_layout
, mtn
.node
);
121 return (unsigned long)layout
->size
;
124 static __always_inline
bool
125 mod_tree_less(struct latch_tree_node
*a
, struct latch_tree_node
*b
)
127 return __mod_tree_val(a
) < __mod_tree_val(b
);
130 static __always_inline
int
131 mod_tree_comp(void *key
, struct latch_tree_node
*n
)
133 unsigned long val
= (unsigned long)key
;
134 unsigned long start
, end
;
136 start
= __mod_tree_val(n
);
140 end
= start
+ __mod_tree_size(n
);
147 static const struct latch_tree_ops mod_tree_ops
= {
148 .less
= mod_tree_less
,
149 .comp
= mod_tree_comp
,
152 static struct mod_tree_root
{
153 struct latch_tree_root root
;
154 unsigned long addr_min
;
155 unsigned long addr_max
;
156 } mod_tree __cacheline_aligned
= {
160 #define module_addr_min mod_tree.addr_min
161 #define module_addr_max mod_tree.addr_max
163 static noinline
void __mod_tree_insert(struct mod_tree_node
*node
)
165 latch_tree_insert(&node
->node
, &mod_tree
.root
, &mod_tree_ops
);
168 static void __mod_tree_remove(struct mod_tree_node
*node
)
170 latch_tree_erase(&node
->node
, &mod_tree
.root
, &mod_tree_ops
);
174 * These modifications: insert, remove_init and remove; are serialized by the
177 static void mod_tree_insert(struct module
*mod
)
179 mod
->core_layout
.mtn
.mod
= mod
;
180 mod
->init_layout
.mtn
.mod
= mod
;
182 __mod_tree_insert(&mod
->core_layout
.mtn
);
183 if (mod
->init_layout
.size
)
184 __mod_tree_insert(&mod
->init_layout
.mtn
);
187 static void mod_tree_remove_init(struct module
*mod
)
189 if (mod
->init_layout
.size
)
190 __mod_tree_remove(&mod
->init_layout
.mtn
);
193 static void mod_tree_remove(struct module
*mod
)
195 __mod_tree_remove(&mod
->core_layout
.mtn
);
196 mod_tree_remove_init(mod
);
199 static struct module
*mod_find(unsigned long addr
)
201 struct latch_tree_node
*ltn
;
203 ltn
= latch_tree_find((void *)addr
, &mod_tree
.root
, &mod_tree_ops
);
207 return container_of(ltn
, struct mod_tree_node
, node
)->mod
;
210 #else /* MODULES_TREE_LOOKUP */
212 static unsigned long module_addr_min
= -1UL, module_addr_max
= 0;
214 static void mod_tree_insert(struct module
*mod
) { }
215 static void mod_tree_remove_init(struct module
*mod
) { }
216 static void mod_tree_remove(struct module
*mod
) { }
218 static struct module
*mod_find(unsigned long addr
)
222 list_for_each_entry_rcu(mod
, &modules
, list
,
223 lockdep_is_held(&module_mutex
)) {
224 if (within_module(addr
, mod
))
231 #endif /* MODULES_TREE_LOOKUP */
234 * Bounds of module text, for speeding up __module_address.
235 * Protected by module_mutex.
237 static void __mod_update_bounds(void *base
, unsigned int size
)
239 unsigned long min
= (unsigned long)base
;
240 unsigned long max
= min
+ size
;
242 if (min
< module_addr_min
)
243 module_addr_min
= min
;
244 if (max
> module_addr_max
)
245 module_addr_max
= max
;
248 static void mod_update_bounds(struct module
*mod
)
250 __mod_update_bounds(mod
->core_layout
.base
, mod
->core_layout
.size
);
251 if (mod
->init_layout
.size
)
252 __mod_update_bounds(mod
->init_layout
.base
, mod
->init_layout
.size
);
255 #ifdef CONFIG_KGDB_KDB
256 struct list_head
*kdb_modules
= &modules
; /* kdb needs the list of modules */
257 #endif /* CONFIG_KGDB_KDB */
259 static void module_assert_mutex(void)
261 lockdep_assert_held(&module_mutex
);
264 static void module_assert_mutex_or_preempt(void)
266 #ifdef CONFIG_LOCKDEP
267 if (unlikely(!debug_locks
))
270 WARN_ON_ONCE(!rcu_read_lock_sched_held() &&
271 !lockdep_is_held(&module_mutex
));
275 static bool sig_enforce
= IS_ENABLED(CONFIG_MODULE_SIG_FORCE
);
276 module_param(sig_enforce
, bool_enable_only
, 0644);
279 * Export sig_enforce kernel cmdline parameter to allow other subsystems rely
280 * on that instead of directly to CONFIG_MODULE_SIG_FORCE config.
282 bool is_module_sig_enforced(void)
286 EXPORT_SYMBOL(is_module_sig_enforced
);
288 void set_module_sig_enforced(void)
293 /* Block module loading/unloading? */
294 int modules_disabled
= 0;
295 core_param(nomodule
, modules_disabled
, bint
, 0);
297 /* Waiting for a module to finish initializing? */
298 static DECLARE_WAIT_QUEUE_HEAD(module_wq
);
300 static BLOCKING_NOTIFIER_HEAD(module_notify_list
);
302 int register_module_notifier(struct notifier_block
*nb
)
304 return blocking_notifier_chain_register(&module_notify_list
, nb
);
306 EXPORT_SYMBOL(register_module_notifier
);
308 int unregister_module_notifier(struct notifier_block
*nb
)
310 return blocking_notifier_chain_unregister(&module_notify_list
, nb
);
312 EXPORT_SYMBOL(unregister_module_notifier
);
315 * We require a truly strong try_module_get(): 0 means success.
316 * Otherwise an error is returned due to ongoing or failed
317 * initialization etc.
319 static inline int strong_try_module_get(struct module
*mod
)
321 BUG_ON(mod
&& mod
->state
== MODULE_STATE_UNFORMED
);
322 if (mod
&& mod
->state
== MODULE_STATE_COMING
)
324 if (try_module_get(mod
))
330 static inline void add_taint_module(struct module
*mod
, unsigned flag
,
331 enum lockdep_ok lockdep_ok
)
333 add_taint(flag
, lockdep_ok
);
334 set_bit(flag
, &mod
->taints
);
338 * A thread that wants to hold a reference to a module only while it
339 * is running can call this to safely exit. nfsd and lockd use this.
341 void __noreturn
__module_put_and_exit(struct module
*mod
, long code
)
346 EXPORT_SYMBOL(__module_put_and_exit
);
348 /* Find a module section: 0 means not found. */
349 static unsigned int find_sec(const struct load_info
*info
, const char *name
)
353 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
354 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
355 /* Alloc bit cleared means "ignore it." */
356 if ((shdr
->sh_flags
& SHF_ALLOC
)
357 && strcmp(info
->secstrings
+ shdr
->sh_name
, name
) == 0)
363 /* Find a module section, or NULL. */
364 static void *section_addr(const struct load_info
*info
, const char *name
)
366 /* Section 0 has sh_addr 0. */
367 return (void *)info
->sechdrs
[find_sec(info
, name
)].sh_addr
;
370 /* Find a module section, or NULL. Fill in number of "objects" in section. */
371 static void *section_objs(const struct load_info
*info
,
376 unsigned int sec
= find_sec(info
, name
);
378 /* Section 0 has sh_addr 0 and sh_size 0. */
379 *num
= info
->sechdrs
[sec
].sh_size
/ object_size
;
380 return (void *)info
->sechdrs
[sec
].sh_addr
;
383 /* Provided by the linker */
384 extern const struct kernel_symbol __start___ksymtab
[];
385 extern const struct kernel_symbol __stop___ksymtab
[];
386 extern const struct kernel_symbol __start___ksymtab_gpl
[];
387 extern const struct kernel_symbol __stop___ksymtab_gpl
[];
388 extern const struct kernel_symbol __start___ksymtab_gpl_future
[];
389 extern const struct kernel_symbol __stop___ksymtab_gpl_future
[];
390 extern const s32 __start___kcrctab
[];
391 extern const s32 __start___kcrctab_gpl
[];
392 extern const s32 __start___kcrctab_gpl_future
[];
393 #ifdef CONFIG_UNUSED_SYMBOLS
394 extern const struct kernel_symbol __start___ksymtab_unused
[];
395 extern const struct kernel_symbol __stop___ksymtab_unused
[];
396 extern const struct kernel_symbol __start___ksymtab_unused_gpl
[];
397 extern const struct kernel_symbol __stop___ksymtab_unused_gpl
[];
398 extern const s32 __start___kcrctab_unused
[];
399 extern const s32 __start___kcrctab_unused_gpl
[];
402 #ifndef CONFIG_MODVERSIONS
403 #define symversion(base, idx) NULL
405 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
408 static bool each_symbol_in_section(const struct symsearch
*arr
,
409 unsigned int arrsize
,
410 struct module
*owner
,
411 bool (*fn
)(const struct symsearch
*syms
,
412 struct module
*owner
,
418 for (j
= 0; j
< arrsize
; j
++) {
419 if (fn(&arr
[j
], owner
, data
))
426 /* Returns true as soon as fn returns true, otherwise false. */
427 static bool each_symbol_section(bool (*fn
)(const struct symsearch
*arr
,
428 struct module
*owner
,
433 static const struct symsearch arr
[] = {
434 { __start___ksymtab
, __stop___ksymtab
, __start___kcrctab
,
435 NOT_GPL_ONLY
, false },
436 { __start___ksymtab_gpl
, __stop___ksymtab_gpl
,
437 __start___kcrctab_gpl
,
439 { __start___ksymtab_gpl_future
, __stop___ksymtab_gpl_future
,
440 __start___kcrctab_gpl_future
,
441 WILL_BE_GPL_ONLY
, false },
442 #ifdef CONFIG_UNUSED_SYMBOLS
443 { __start___ksymtab_unused
, __stop___ksymtab_unused
,
444 __start___kcrctab_unused
,
445 NOT_GPL_ONLY
, true },
446 { __start___ksymtab_unused_gpl
, __stop___ksymtab_unused_gpl
,
447 __start___kcrctab_unused_gpl
,
452 module_assert_mutex_or_preempt();
454 if (each_symbol_in_section(arr
, ARRAY_SIZE(arr
), NULL
, fn
, data
))
457 list_for_each_entry_rcu(mod
, &modules
, list
,
458 lockdep_is_held(&module_mutex
)) {
459 struct symsearch arr
[] = {
460 { mod
->syms
, mod
->syms
+ mod
->num_syms
, mod
->crcs
,
461 NOT_GPL_ONLY
, false },
462 { mod
->gpl_syms
, mod
->gpl_syms
+ mod
->num_gpl_syms
,
465 { mod
->gpl_future_syms
,
466 mod
->gpl_future_syms
+ mod
->num_gpl_future_syms
,
467 mod
->gpl_future_crcs
,
468 WILL_BE_GPL_ONLY
, false },
469 #ifdef CONFIG_UNUSED_SYMBOLS
471 mod
->unused_syms
+ mod
->num_unused_syms
,
473 NOT_GPL_ONLY
, true },
474 { mod
->unused_gpl_syms
,
475 mod
->unused_gpl_syms
+ mod
->num_unused_gpl_syms
,
476 mod
->unused_gpl_crcs
,
481 if (mod
->state
== MODULE_STATE_UNFORMED
)
484 if (each_symbol_in_section(arr
, ARRAY_SIZE(arr
), mod
, fn
, data
))
490 struct find_symbol_arg
{
497 struct module
*owner
;
499 const struct kernel_symbol
*sym
;
500 enum mod_license license
;
503 static bool check_exported_symbol(const struct symsearch
*syms
,
504 struct module
*owner
,
505 unsigned int symnum
, void *data
)
507 struct find_symbol_arg
*fsa
= data
;
510 if (syms
->license
== GPL_ONLY
)
512 if (syms
->license
== WILL_BE_GPL_ONLY
&& fsa
->warn
) {
513 pr_warn("Symbol %s is being used by a non-GPL module, "
514 "which will not be allowed in the future\n",
519 #ifdef CONFIG_UNUSED_SYMBOLS
520 if (syms
->unused
&& fsa
->warn
) {
521 pr_warn("Symbol %s is marked as UNUSED, however this module is "
522 "using it.\n", fsa
->name
);
523 pr_warn("This symbol will go away in the future.\n");
524 pr_warn("Please evaluate if this is the right api to use and "
525 "if it really is, submit a report to the linux kernel "
526 "mailing list together with submitting your code for "
532 fsa
->crc
= symversion(syms
->crcs
, symnum
);
533 fsa
->sym
= &syms
->start
[symnum
];
534 fsa
->license
= syms
->license
;
538 static unsigned long kernel_symbol_value(const struct kernel_symbol
*sym
)
540 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
541 return (unsigned long)offset_to_ptr(&sym
->value_offset
);
547 static const char *kernel_symbol_name(const struct kernel_symbol
*sym
)
549 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
550 return offset_to_ptr(&sym
->name_offset
);
556 static const char *kernel_symbol_namespace(const struct kernel_symbol
*sym
)
558 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
559 if (!sym
->namespace_offset
)
561 return offset_to_ptr(&sym
->namespace_offset
);
563 return sym
->namespace;
567 static int cmp_name(const void *name
, const void *sym
)
569 return strcmp(name
, kernel_symbol_name(sym
));
572 static bool find_exported_symbol_in_section(const struct symsearch
*syms
,
573 struct module
*owner
,
576 struct find_symbol_arg
*fsa
= data
;
577 struct kernel_symbol
*sym
;
579 sym
= bsearch(fsa
->name
, syms
->start
, syms
->stop
- syms
->start
,
580 sizeof(struct kernel_symbol
), cmp_name
);
582 if (sym
!= NULL
&& check_exported_symbol(syms
, owner
,
583 sym
- syms
->start
, data
))
589 /* Find an exported symbol and return it, along with, (optional) crc and
590 * (optional) module which owns it. Needs preempt disabled or module_mutex. */
591 static const struct kernel_symbol
*find_symbol(const char *name
,
592 struct module
**owner
,
594 enum mod_license
*license
,
598 struct find_symbol_arg fsa
;
604 if (each_symbol_section(find_exported_symbol_in_section
, &fsa
)) {
610 *license
= fsa
.license
;
614 pr_debug("Failed to find symbol %s\n", name
);
619 * Search for module by name: must hold module_mutex (or preempt disabled
620 * for read-only access).
622 static struct module
*find_module_all(const char *name
, size_t len
,
627 module_assert_mutex_or_preempt();
629 list_for_each_entry_rcu(mod
, &modules
, list
,
630 lockdep_is_held(&module_mutex
)) {
631 if (!even_unformed
&& mod
->state
== MODULE_STATE_UNFORMED
)
633 if (strlen(mod
->name
) == len
&& !memcmp(mod
->name
, name
, len
))
639 struct module
*find_module(const char *name
)
641 module_assert_mutex();
642 return find_module_all(name
, strlen(name
), false);
644 EXPORT_SYMBOL_GPL(find_module
);
648 static inline void __percpu
*mod_percpu(struct module
*mod
)
653 static int percpu_modalloc(struct module
*mod
, struct load_info
*info
)
655 Elf_Shdr
*pcpusec
= &info
->sechdrs
[info
->index
.pcpu
];
656 unsigned long align
= pcpusec
->sh_addralign
;
658 if (!pcpusec
->sh_size
)
661 if (align
> PAGE_SIZE
) {
662 pr_warn("%s: per-cpu alignment %li > %li\n",
663 mod
->name
, align
, PAGE_SIZE
);
667 mod
->percpu
= __alloc_reserved_percpu(pcpusec
->sh_size
, align
);
669 pr_warn("%s: Could not allocate %lu bytes percpu data\n",
670 mod
->name
, (unsigned long)pcpusec
->sh_size
);
673 mod
->percpu_size
= pcpusec
->sh_size
;
677 static void percpu_modfree(struct module
*mod
)
679 free_percpu(mod
->percpu
);
682 static unsigned int find_pcpusec(struct load_info
*info
)
684 return find_sec(info
, ".data..percpu");
687 static void percpu_modcopy(struct module
*mod
,
688 const void *from
, unsigned long size
)
692 for_each_possible_cpu(cpu
)
693 memcpy(per_cpu_ptr(mod
->percpu
, cpu
), from
, size
);
696 bool __is_module_percpu_address(unsigned long addr
, unsigned long *can_addr
)
703 list_for_each_entry_rcu(mod
, &modules
, list
) {
704 if (mod
->state
== MODULE_STATE_UNFORMED
)
706 if (!mod
->percpu_size
)
708 for_each_possible_cpu(cpu
) {
709 void *start
= per_cpu_ptr(mod
->percpu
, cpu
);
710 void *va
= (void *)addr
;
712 if (va
>= start
&& va
< start
+ mod
->percpu_size
) {
714 *can_addr
= (unsigned long) (va
- start
);
715 *can_addr
+= (unsigned long)
716 per_cpu_ptr(mod
->percpu
,
730 * is_module_percpu_address - test whether address is from module static percpu
731 * @addr: address to test
733 * Test whether @addr belongs to module static percpu area.
736 * %true if @addr is from module static percpu area
738 bool is_module_percpu_address(unsigned long addr
)
740 return __is_module_percpu_address(addr
, NULL
);
743 #else /* ... !CONFIG_SMP */
745 static inline void __percpu
*mod_percpu(struct module
*mod
)
749 static int percpu_modalloc(struct module
*mod
, struct load_info
*info
)
751 /* UP modules shouldn't have this section: ENOMEM isn't quite right */
752 if (info
->sechdrs
[info
->index
.pcpu
].sh_size
!= 0)
756 static inline void percpu_modfree(struct module
*mod
)
759 static unsigned int find_pcpusec(struct load_info
*info
)
763 static inline void percpu_modcopy(struct module
*mod
,
764 const void *from
, unsigned long size
)
766 /* pcpusec should be 0, and size of that section should be 0. */
769 bool is_module_percpu_address(unsigned long addr
)
774 bool __is_module_percpu_address(unsigned long addr
, unsigned long *can_addr
)
779 #endif /* CONFIG_SMP */
781 #define MODINFO_ATTR(field) \
782 static void setup_modinfo_##field(struct module *mod, const char *s) \
784 mod->field = kstrdup(s, GFP_KERNEL); \
786 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
787 struct module_kobject *mk, char *buffer) \
789 return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \
791 static int modinfo_##field##_exists(struct module *mod) \
793 return mod->field != NULL; \
795 static void free_modinfo_##field(struct module *mod) \
800 static struct module_attribute modinfo_##field = { \
801 .attr = { .name = __stringify(field), .mode = 0444 }, \
802 .show = show_modinfo_##field, \
803 .setup = setup_modinfo_##field, \
804 .test = modinfo_##field##_exists, \
805 .free = free_modinfo_##field, \
808 MODINFO_ATTR(version
);
809 MODINFO_ATTR(srcversion
);
811 static char last_unloaded_module
[MODULE_NAME_LEN
+1];
813 #ifdef CONFIG_MODULE_UNLOAD
815 EXPORT_TRACEPOINT_SYMBOL(module_get
);
817 /* MODULE_REF_BASE is the base reference count by kmodule loader. */
818 #define MODULE_REF_BASE 1
820 /* Init the unload section of the module. */
821 static int module_unload_init(struct module
*mod
)
824 * Initialize reference counter to MODULE_REF_BASE.
825 * refcnt == 0 means module is going.
827 atomic_set(&mod
->refcnt
, MODULE_REF_BASE
);
829 INIT_LIST_HEAD(&mod
->source_list
);
830 INIT_LIST_HEAD(&mod
->target_list
);
832 /* Hold reference count during initialization. */
833 atomic_inc(&mod
->refcnt
);
838 /* Does a already use b? */
839 static int already_uses(struct module
*a
, struct module
*b
)
841 struct module_use
*use
;
843 list_for_each_entry(use
, &b
->source_list
, source_list
) {
844 if (use
->source
== a
) {
845 pr_debug("%s uses %s!\n", a
->name
, b
->name
);
849 pr_debug("%s does not use %s!\n", a
->name
, b
->name
);
855 * - we add 'a' as a "source", 'b' as a "target" of module use
856 * - the module_use is added to the list of 'b' sources (so
857 * 'b' can walk the list to see who sourced them), and of 'a'
858 * targets (so 'a' can see what modules it targets).
860 static int add_module_usage(struct module
*a
, struct module
*b
)
862 struct module_use
*use
;
864 pr_debug("Allocating new usage for %s.\n", a
->name
);
865 use
= kmalloc(sizeof(*use
), GFP_ATOMIC
);
871 list_add(&use
->source_list
, &b
->source_list
);
872 list_add(&use
->target_list
, &a
->target_list
);
876 /* Module a uses b: caller needs module_mutex() */
877 static int ref_module(struct module
*a
, struct module
*b
)
881 if (b
== NULL
|| already_uses(a
, b
))
884 /* If module isn't available, we fail. */
885 err
= strong_try_module_get(b
);
889 err
= add_module_usage(a
, b
);
897 /* Clear the unload stuff of the module. */
898 static void module_unload_free(struct module
*mod
)
900 struct module_use
*use
, *tmp
;
902 mutex_lock(&module_mutex
);
903 list_for_each_entry_safe(use
, tmp
, &mod
->target_list
, target_list
) {
904 struct module
*i
= use
->target
;
905 pr_debug("%s unusing %s\n", mod
->name
, i
->name
);
907 list_del(&use
->source_list
);
908 list_del(&use
->target_list
);
911 mutex_unlock(&module_mutex
);
914 #ifdef CONFIG_MODULE_FORCE_UNLOAD
915 static inline int try_force_unload(unsigned int flags
)
917 int ret
= (flags
& O_TRUNC
);
919 add_taint(TAINT_FORCED_RMMOD
, LOCKDEP_NOW_UNRELIABLE
);
923 static inline int try_force_unload(unsigned int flags
)
927 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
929 /* Try to release refcount of module, 0 means success. */
930 static int try_release_module_ref(struct module
*mod
)
934 /* Try to decrement refcnt which we set at loading */
935 ret
= atomic_sub_return(MODULE_REF_BASE
, &mod
->refcnt
);
938 /* Someone can put this right now, recover with checking */
939 ret
= atomic_add_unless(&mod
->refcnt
, MODULE_REF_BASE
, 0);
944 static int try_stop_module(struct module
*mod
, int flags
, int *forced
)
946 /* If it's not unused, quit unless we're forcing. */
947 if (try_release_module_ref(mod
) != 0) {
948 *forced
= try_force_unload(flags
);
953 /* Mark it as dying. */
954 mod
->state
= MODULE_STATE_GOING
;
960 * module_refcount - return the refcount or -1 if unloading
962 * @mod: the module we're checking
965 * -1 if the module is in the process of unloading
966 * otherwise the number of references in the kernel to the module
968 int module_refcount(struct module
*mod
)
970 return atomic_read(&mod
->refcnt
) - MODULE_REF_BASE
;
972 EXPORT_SYMBOL(module_refcount
);
974 /* This exists whether we can unload or not */
975 static void free_module(struct module
*mod
);
977 SYSCALL_DEFINE2(delete_module
, const char __user
*, name_user
,
981 char name
[MODULE_NAME_LEN
];
984 if (!capable(CAP_SYS_MODULE
) || modules_disabled
)
987 if (strncpy_from_user(name
, name_user
, MODULE_NAME_LEN
-1) < 0)
989 name
[MODULE_NAME_LEN
-1] = '\0';
991 audit_log_kern_module(name
);
993 if (mutex_lock_interruptible(&module_mutex
) != 0)
996 mod
= find_module(name
);
1002 if (!list_empty(&mod
->source_list
)) {
1003 /* Other modules depend on us: get rid of them first. */
1008 /* Doing init or already dying? */
1009 if (mod
->state
!= MODULE_STATE_LIVE
) {
1010 /* FIXME: if (force), slam module count damn the torpedoes */
1011 pr_debug("%s already dying\n", mod
->name
);
1016 /* If it has an init func, it must have an exit func to unload */
1017 if (mod
->init
&& !mod
->exit
) {
1018 forced
= try_force_unload(flags
);
1020 /* This module can't be removed */
1026 /* Stop the machine so refcounts can't move and disable module. */
1027 ret
= try_stop_module(mod
, flags
, &forced
);
1031 mutex_unlock(&module_mutex
);
1032 /* Final destruction now no one is using it. */
1033 if (mod
->exit
!= NULL
)
1035 blocking_notifier_call_chain(&module_notify_list
,
1036 MODULE_STATE_GOING
, mod
);
1037 klp_module_going(mod
);
1038 ftrace_release_mod(mod
);
1040 async_synchronize_full();
1042 /* Store the name of the last unloaded module for diagnostic purposes */
1043 strlcpy(last_unloaded_module
, mod
->name
, sizeof(last_unloaded_module
));
1046 /* someone could wait for the module in add_unformed_module() */
1047 wake_up_all(&module_wq
);
1050 mutex_unlock(&module_mutex
);
1054 static inline void print_unload_info(struct seq_file
*m
, struct module
*mod
)
1056 struct module_use
*use
;
1057 int printed_something
= 0;
1059 seq_printf(m
, " %i ", module_refcount(mod
));
1062 * Always include a trailing , so userspace can differentiate
1063 * between this and the old multi-field proc format.
1065 list_for_each_entry(use
, &mod
->source_list
, source_list
) {
1066 printed_something
= 1;
1067 seq_printf(m
, "%s,", use
->source
->name
);
1070 if (mod
->init
!= NULL
&& mod
->exit
== NULL
) {
1071 printed_something
= 1;
1072 seq_puts(m
, "[permanent],");
1075 if (!printed_something
)
1079 void __symbol_put(const char *symbol
)
1081 struct module
*owner
;
1084 if (!find_symbol(symbol
, &owner
, NULL
, NULL
, true, false))
1089 EXPORT_SYMBOL(__symbol_put
);
1091 /* Note this assumes addr is a function, which it currently always is. */
1092 void symbol_put_addr(void *addr
)
1094 struct module
*modaddr
;
1095 unsigned long a
= (unsigned long)dereference_function_descriptor(addr
);
1097 if (core_kernel_text(a
))
1101 * Even though we hold a reference on the module; we still need to
1102 * disable preemption in order to safely traverse the data structure.
1105 modaddr
= __module_text_address(a
);
1107 module_put(modaddr
);
1110 EXPORT_SYMBOL_GPL(symbol_put_addr
);
1112 static ssize_t
show_refcnt(struct module_attribute
*mattr
,
1113 struct module_kobject
*mk
, char *buffer
)
1115 return sprintf(buffer
, "%i\n", module_refcount(mk
->mod
));
1118 static struct module_attribute modinfo_refcnt
=
1119 __ATTR(refcnt
, 0444, show_refcnt
, NULL
);
1121 void __module_get(struct module
*module
)
1125 atomic_inc(&module
->refcnt
);
1126 trace_module_get(module
, _RET_IP_
);
1130 EXPORT_SYMBOL(__module_get
);
1132 bool try_module_get(struct module
*module
)
1138 /* Note: here, we can fail to get a reference */
1139 if (likely(module_is_live(module
) &&
1140 atomic_inc_not_zero(&module
->refcnt
) != 0))
1141 trace_module_get(module
, _RET_IP_
);
1149 EXPORT_SYMBOL(try_module_get
);
1151 void module_put(struct module
*module
)
1157 ret
= atomic_dec_if_positive(&module
->refcnt
);
1158 WARN_ON(ret
< 0); /* Failed to put refcount */
1159 trace_module_put(module
, _RET_IP_
);
1163 EXPORT_SYMBOL(module_put
);
1165 #else /* !CONFIG_MODULE_UNLOAD */
1166 static inline void print_unload_info(struct seq_file
*m
, struct module
*mod
)
1168 /* We don't know the usage count, or what modules are using. */
1169 seq_puts(m
, " - -");
1172 static inline void module_unload_free(struct module
*mod
)
1176 static int ref_module(struct module
*a
, struct module
*b
)
1178 return strong_try_module_get(b
);
1181 static inline int module_unload_init(struct module
*mod
)
1185 #endif /* CONFIG_MODULE_UNLOAD */
1187 static size_t module_flags_taint(struct module
*mod
, char *buf
)
1192 for (i
= 0; i
< TAINT_FLAGS_COUNT
; i
++) {
1193 if (taint_flags
[i
].module
&& test_bit(i
, &mod
->taints
))
1194 buf
[l
++] = taint_flags
[i
].c_true
;
1200 static ssize_t
show_initstate(struct module_attribute
*mattr
,
1201 struct module_kobject
*mk
, char *buffer
)
1203 const char *state
= "unknown";
1205 switch (mk
->mod
->state
) {
1206 case MODULE_STATE_LIVE
:
1209 case MODULE_STATE_COMING
:
1212 case MODULE_STATE_GOING
:
1218 return sprintf(buffer
, "%s\n", state
);
1221 static struct module_attribute modinfo_initstate
=
1222 __ATTR(initstate
, 0444, show_initstate
, NULL
);
1224 static ssize_t
store_uevent(struct module_attribute
*mattr
,
1225 struct module_kobject
*mk
,
1226 const char *buffer
, size_t count
)
1230 rc
= kobject_synth_uevent(&mk
->kobj
, buffer
, count
);
1231 return rc
? rc
: count
;
1234 struct module_attribute module_uevent
=
1235 __ATTR(uevent
, 0200, NULL
, store_uevent
);
1237 static ssize_t
show_coresize(struct module_attribute
*mattr
,
1238 struct module_kobject
*mk
, char *buffer
)
1240 return sprintf(buffer
, "%u\n", mk
->mod
->core_layout
.size
);
1243 static struct module_attribute modinfo_coresize
=
1244 __ATTR(coresize
, 0444, show_coresize
, NULL
);
1246 static ssize_t
show_initsize(struct module_attribute
*mattr
,
1247 struct module_kobject
*mk
, char *buffer
)
1249 return sprintf(buffer
, "%u\n", mk
->mod
->init_layout
.size
);
1252 static struct module_attribute modinfo_initsize
=
1253 __ATTR(initsize
, 0444, show_initsize
, NULL
);
1255 static ssize_t
show_taint(struct module_attribute
*mattr
,
1256 struct module_kobject
*mk
, char *buffer
)
1260 l
= module_flags_taint(mk
->mod
, buffer
);
1265 static struct module_attribute modinfo_taint
=
1266 __ATTR(taint
, 0444, show_taint
, NULL
);
1268 static struct module_attribute
*modinfo_attrs
[] = {
1271 &modinfo_srcversion
,
1276 #ifdef CONFIG_MODULE_UNLOAD
1282 static const char vermagic
[] = VERMAGIC_STRING
;
1284 static int try_to_force_load(struct module
*mod
, const char *reason
)
1286 #ifdef CONFIG_MODULE_FORCE_LOAD
1287 if (!test_taint(TAINT_FORCED_MODULE
))
1288 pr_warn("%s: %s: kernel tainted.\n", mod
->name
, reason
);
1289 add_taint_module(mod
, TAINT_FORCED_MODULE
, LOCKDEP_NOW_UNRELIABLE
);
1296 #ifdef CONFIG_MODVERSIONS
1298 static u32
resolve_rel_crc(const s32
*crc
)
1300 return *(u32
*)((void *)crc
+ *crc
);
1303 static int check_version(const struct load_info
*info
,
1304 const char *symname
,
1308 Elf_Shdr
*sechdrs
= info
->sechdrs
;
1309 unsigned int versindex
= info
->index
.vers
;
1310 unsigned int i
, num_versions
;
1311 struct modversion_info
*versions
;
1313 /* Exporting module didn't supply crcs? OK, we're already tainted. */
1317 /* No versions at all? modprobe --force does this. */
1319 return try_to_force_load(mod
, symname
) == 0;
1321 versions
= (void *) sechdrs
[versindex
].sh_addr
;
1322 num_versions
= sechdrs
[versindex
].sh_size
1323 / sizeof(struct modversion_info
);
1325 for (i
= 0; i
< num_versions
; i
++) {
1328 if (strcmp(versions
[i
].name
, symname
) != 0)
1331 if (IS_ENABLED(CONFIG_MODULE_REL_CRCS
))
1332 crcval
= resolve_rel_crc(crc
);
1335 if (versions
[i
].crc
== crcval
)
1337 pr_debug("Found checksum %X vs module %lX\n",
1338 crcval
, versions
[i
].crc
);
1342 /* Broken toolchain. Warn once, then let it go.. */
1343 pr_warn_once("%s: no symbol version for %s\n", info
->name
, symname
);
1347 pr_warn("%s: disagrees about version of symbol %s\n",
1348 info
->name
, symname
);
1352 static inline int check_modstruct_version(const struct load_info
*info
,
1358 * Since this should be found in kernel (which can't be removed), no
1359 * locking is necessary -- use preempt_disable() to placate lockdep.
1362 if (!find_symbol("module_layout", NULL
, &crc
, NULL
, true, false)) {
1367 return check_version(info
, "module_layout", mod
, crc
);
1370 /* First part is kernel version, which we ignore if module has crcs. */
1371 static inline int same_magic(const char *amagic
, const char *bmagic
,
1375 amagic
+= strcspn(amagic
, " ");
1376 bmagic
+= strcspn(bmagic
, " ");
1378 return strcmp(amagic
, bmagic
) == 0;
1381 static inline int check_version(const struct load_info
*info
,
1382 const char *symname
,
1389 static inline int check_modstruct_version(const struct load_info
*info
,
1395 static inline int same_magic(const char *amagic
, const char *bmagic
,
1398 return strcmp(amagic
, bmagic
) == 0;
1400 #endif /* CONFIG_MODVERSIONS */
1402 static char *get_modinfo(const struct load_info
*info
, const char *tag
);
1403 static char *get_next_modinfo(const struct load_info
*info
, const char *tag
,
1406 static int verify_namespace_is_imported(const struct load_info
*info
,
1407 const struct kernel_symbol
*sym
,
1410 const char *namespace;
1411 char *imported_namespace
;
1413 namespace = kernel_symbol_namespace(sym
);
1414 if (namespace && namespace[0]) {
1415 imported_namespace
= get_modinfo(info
, "import_ns");
1416 while (imported_namespace
) {
1417 if (strcmp(namespace, imported_namespace
) == 0)
1419 imported_namespace
= get_next_modinfo(
1420 info
, "import_ns", imported_namespace
);
1422 #ifdef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS
1427 "%s: module uses symbol (%s) from namespace %s, but does not import it.\n",
1428 mod
->name
, kernel_symbol_name(sym
), namespace);
1429 #ifndef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS
1436 static bool inherit_taint(struct module
*mod
, struct module
*owner
)
1438 if (!owner
|| !test_bit(TAINT_PROPRIETARY_MODULE
, &owner
->taints
))
1441 if (mod
->using_gplonly_symbols
) {
1442 pr_err("%s: module using GPL-only symbols uses symbols from proprietary module %s.\n",
1443 mod
->name
, owner
->name
);
1447 if (!test_bit(TAINT_PROPRIETARY_MODULE
, &mod
->taints
)) {
1448 pr_warn("%s: module uses symbols from proprietary module %s, inheriting taint.\n",
1449 mod
->name
, owner
->name
);
1450 set_bit(TAINT_PROPRIETARY_MODULE
, &mod
->taints
);
1455 /* Resolve a symbol for this module. I.e. if we find one, record usage. */
1456 static const struct kernel_symbol
*resolve_symbol(struct module
*mod
,
1457 const struct load_info
*info
,
1461 struct module
*owner
;
1462 const struct kernel_symbol
*sym
;
1464 enum mod_license license
;
1468 * The module_mutex should not be a heavily contended lock;
1469 * if we get the occasional sleep here, we'll go an extra iteration
1470 * in the wait_event_interruptible(), which is harmless.
1472 sched_annotate_sleep();
1473 mutex_lock(&module_mutex
);
1474 sym
= find_symbol(name
, &owner
, &crc
, &license
,
1475 !(mod
->taints
& (1 << TAINT_PROPRIETARY_MODULE
)), true);
1479 if (license
== GPL_ONLY
)
1480 mod
->using_gplonly_symbols
= true;
1482 if (!inherit_taint(mod
, owner
)) {
1487 if (!check_version(info
, name
, mod
, crc
)) {
1488 sym
= ERR_PTR(-EINVAL
);
1492 err
= verify_namespace_is_imported(info
, sym
, mod
);
1498 err
= ref_module(mod
, owner
);
1505 /* We must make copy under the lock if we failed to get ref. */
1506 strncpy(ownername
, module_name(owner
), MODULE_NAME_LEN
);
1508 mutex_unlock(&module_mutex
);
1512 static const struct kernel_symbol
*
1513 resolve_symbol_wait(struct module
*mod
,
1514 const struct load_info
*info
,
1517 const struct kernel_symbol
*ksym
;
1518 char owner
[MODULE_NAME_LEN
];
1520 if (wait_event_interruptible_timeout(module_wq
,
1521 !IS_ERR(ksym
= resolve_symbol(mod
, info
, name
, owner
))
1522 || PTR_ERR(ksym
) != -EBUSY
,
1524 pr_warn("%s: gave up waiting for init of module %s.\n",
1531 * /sys/module/foo/sections stuff
1532 * J. Corbet <corbet@lwn.net>
1536 #ifdef CONFIG_KALLSYMS
1537 static inline bool sect_empty(const Elf_Shdr
*sect
)
1539 return !(sect
->sh_flags
& SHF_ALLOC
) || sect
->sh_size
== 0;
1542 struct module_sect_attr
{
1543 struct bin_attribute battr
;
1544 unsigned long address
;
1547 struct module_sect_attrs
{
1548 struct attribute_group grp
;
1549 unsigned int nsections
;
1550 struct module_sect_attr attrs
[];
1553 #define MODULE_SECT_READ_SIZE (3 /* "0x", "\n" */ + (BITS_PER_LONG / 4))
1554 static ssize_t
module_sect_read(struct file
*file
, struct kobject
*kobj
,
1555 struct bin_attribute
*battr
,
1556 char *buf
, loff_t pos
, size_t count
)
1558 struct module_sect_attr
*sattr
=
1559 container_of(battr
, struct module_sect_attr
, battr
);
1560 char bounce
[MODULE_SECT_READ_SIZE
+ 1];
1567 * Since we're a binary read handler, we must account for the
1568 * trailing NUL byte that sprintf will write: if "buf" is
1569 * too small to hold the NUL, or the NUL is exactly the last
1570 * byte, the read will look like it got truncated by one byte.
1571 * Since there is no way to ask sprintf nicely to not write
1572 * the NUL, we have to use a bounce buffer.
1574 wrote
= scnprintf(bounce
, sizeof(bounce
), "0x%px\n",
1575 kallsyms_show_value(file
->f_cred
)
1576 ? (void *)sattr
->address
: NULL
);
1577 count
= min(count
, wrote
);
1578 memcpy(buf
, bounce
, count
);
1583 static void free_sect_attrs(struct module_sect_attrs
*sect_attrs
)
1585 unsigned int section
;
1587 for (section
= 0; section
< sect_attrs
->nsections
; section
++)
1588 kfree(sect_attrs
->attrs
[section
].battr
.attr
.name
);
1592 static void add_sect_attrs(struct module
*mod
, const struct load_info
*info
)
1594 unsigned int nloaded
= 0, i
, size
[2];
1595 struct module_sect_attrs
*sect_attrs
;
1596 struct module_sect_attr
*sattr
;
1597 struct bin_attribute
**gattr
;
1599 /* Count loaded sections and allocate structures */
1600 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
1601 if (!sect_empty(&info
->sechdrs
[i
]))
1603 size
[0] = ALIGN(struct_size(sect_attrs
, attrs
, nloaded
),
1604 sizeof(sect_attrs
->grp
.bin_attrs
[0]));
1605 size
[1] = (nloaded
+ 1) * sizeof(sect_attrs
->grp
.bin_attrs
[0]);
1606 sect_attrs
= kzalloc(size
[0] + size
[1], GFP_KERNEL
);
1607 if (sect_attrs
== NULL
)
1610 /* Setup section attributes. */
1611 sect_attrs
->grp
.name
= "sections";
1612 sect_attrs
->grp
.bin_attrs
= (void *)sect_attrs
+ size
[0];
1614 sect_attrs
->nsections
= 0;
1615 sattr
= §_attrs
->attrs
[0];
1616 gattr
= §_attrs
->grp
.bin_attrs
[0];
1617 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++) {
1618 Elf_Shdr
*sec
= &info
->sechdrs
[i
];
1619 if (sect_empty(sec
))
1621 sysfs_bin_attr_init(&sattr
->battr
);
1622 sattr
->address
= sec
->sh_addr
;
1623 sattr
->battr
.attr
.name
=
1624 kstrdup(info
->secstrings
+ sec
->sh_name
, GFP_KERNEL
);
1625 if (sattr
->battr
.attr
.name
== NULL
)
1627 sect_attrs
->nsections
++;
1628 sattr
->battr
.read
= module_sect_read
;
1629 sattr
->battr
.size
= MODULE_SECT_READ_SIZE
;
1630 sattr
->battr
.attr
.mode
= 0400;
1631 *(gattr
++) = &(sattr
++)->battr
;
1635 if (sysfs_create_group(&mod
->mkobj
.kobj
, §_attrs
->grp
))
1638 mod
->sect_attrs
= sect_attrs
;
1641 free_sect_attrs(sect_attrs
);
1644 static void remove_sect_attrs(struct module
*mod
)
1646 if (mod
->sect_attrs
) {
1647 sysfs_remove_group(&mod
->mkobj
.kobj
,
1648 &mod
->sect_attrs
->grp
);
1649 /* We are positive that no one is using any sect attrs
1650 * at this point. Deallocate immediately. */
1651 free_sect_attrs(mod
->sect_attrs
);
1652 mod
->sect_attrs
= NULL
;
1657 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1660 struct module_notes_attrs
{
1661 struct kobject
*dir
;
1663 struct bin_attribute attrs
[];
1666 static ssize_t
module_notes_read(struct file
*filp
, struct kobject
*kobj
,
1667 struct bin_attribute
*bin_attr
,
1668 char *buf
, loff_t pos
, size_t count
)
1671 * The caller checked the pos and count against our size.
1673 memcpy(buf
, bin_attr
->private + pos
, count
);
1677 static void free_notes_attrs(struct module_notes_attrs
*notes_attrs
,
1680 if (notes_attrs
->dir
) {
1682 sysfs_remove_bin_file(notes_attrs
->dir
,
1683 ¬es_attrs
->attrs
[i
]);
1684 kobject_put(notes_attrs
->dir
);
1689 static void add_notes_attrs(struct module
*mod
, const struct load_info
*info
)
1691 unsigned int notes
, loaded
, i
;
1692 struct module_notes_attrs
*notes_attrs
;
1693 struct bin_attribute
*nattr
;
1695 /* failed to create section attributes, so can't create notes */
1696 if (!mod
->sect_attrs
)
1699 /* Count notes sections and allocate structures. */
1701 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
1702 if (!sect_empty(&info
->sechdrs
[i
]) &&
1703 (info
->sechdrs
[i
].sh_type
== SHT_NOTE
))
1709 notes_attrs
= kzalloc(struct_size(notes_attrs
, attrs
, notes
),
1711 if (notes_attrs
== NULL
)
1714 notes_attrs
->notes
= notes
;
1715 nattr
= ¬es_attrs
->attrs
[0];
1716 for (loaded
= i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
1717 if (sect_empty(&info
->sechdrs
[i
]))
1719 if (info
->sechdrs
[i
].sh_type
== SHT_NOTE
) {
1720 sysfs_bin_attr_init(nattr
);
1721 nattr
->attr
.name
= mod
->sect_attrs
->attrs
[loaded
].battr
.attr
.name
;
1722 nattr
->attr
.mode
= S_IRUGO
;
1723 nattr
->size
= info
->sechdrs
[i
].sh_size
;
1724 nattr
->private = (void *) info
->sechdrs
[i
].sh_addr
;
1725 nattr
->read
= module_notes_read
;
1731 notes_attrs
->dir
= kobject_create_and_add("notes", &mod
->mkobj
.kobj
);
1732 if (!notes_attrs
->dir
)
1735 for (i
= 0; i
< notes
; ++i
)
1736 if (sysfs_create_bin_file(notes_attrs
->dir
,
1737 ¬es_attrs
->attrs
[i
]))
1740 mod
->notes_attrs
= notes_attrs
;
1744 free_notes_attrs(notes_attrs
, i
);
1747 static void remove_notes_attrs(struct module
*mod
)
1749 if (mod
->notes_attrs
)
1750 free_notes_attrs(mod
->notes_attrs
, mod
->notes_attrs
->notes
);
1755 static inline void add_sect_attrs(struct module
*mod
,
1756 const struct load_info
*info
)
1760 static inline void remove_sect_attrs(struct module
*mod
)
1764 static inline void add_notes_attrs(struct module
*mod
,
1765 const struct load_info
*info
)
1769 static inline void remove_notes_attrs(struct module
*mod
)
1772 #endif /* CONFIG_KALLSYMS */
1774 static void del_usage_links(struct module
*mod
)
1776 #ifdef CONFIG_MODULE_UNLOAD
1777 struct module_use
*use
;
1779 mutex_lock(&module_mutex
);
1780 list_for_each_entry(use
, &mod
->target_list
, target_list
)
1781 sysfs_remove_link(use
->target
->holders_dir
, mod
->name
);
1782 mutex_unlock(&module_mutex
);
1786 static int add_usage_links(struct module
*mod
)
1789 #ifdef CONFIG_MODULE_UNLOAD
1790 struct module_use
*use
;
1792 mutex_lock(&module_mutex
);
1793 list_for_each_entry(use
, &mod
->target_list
, target_list
) {
1794 ret
= sysfs_create_link(use
->target
->holders_dir
,
1795 &mod
->mkobj
.kobj
, mod
->name
);
1799 mutex_unlock(&module_mutex
);
1801 del_usage_links(mod
);
1806 static void module_remove_modinfo_attrs(struct module
*mod
, int end
);
1808 static int module_add_modinfo_attrs(struct module
*mod
)
1810 struct module_attribute
*attr
;
1811 struct module_attribute
*temp_attr
;
1815 mod
->modinfo_attrs
= kzalloc((sizeof(struct module_attribute
) *
1816 (ARRAY_SIZE(modinfo_attrs
) + 1)),
1818 if (!mod
->modinfo_attrs
)
1821 temp_attr
= mod
->modinfo_attrs
;
1822 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
1823 if (!attr
->test
|| attr
->test(mod
)) {
1824 memcpy(temp_attr
, attr
, sizeof(*temp_attr
));
1825 sysfs_attr_init(&temp_attr
->attr
);
1826 error
= sysfs_create_file(&mod
->mkobj
.kobj
,
1838 module_remove_modinfo_attrs(mod
, --i
);
1840 kfree(mod
->modinfo_attrs
);
1844 static void module_remove_modinfo_attrs(struct module
*mod
, int end
)
1846 struct module_attribute
*attr
;
1849 for (i
= 0; (attr
= &mod
->modinfo_attrs
[i
]); i
++) {
1850 if (end
>= 0 && i
> end
)
1852 /* pick a field to test for end of list */
1853 if (!attr
->attr
.name
)
1855 sysfs_remove_file(&mod
->mkobj
.kobj
, &attr
->attr
);
1859 kfree(mod
->modinfo_attrs
);
1862 static void mod_kobject_put(struct module
*mod
)
1864 DECLARE_COMPLETION_ONSTACK(c
);
1865 mod
->mkobj
.kobj_completion
= &c
;
1866 kobject_put(&mod
->mkobj
.kobj
);
1867 wait_for_completion(&c
);
1870 static int mod_sysfs_init(struct module
*mod
)
1873 struct kobject
*kobj
;
1875 if (!module_sysfs_initialized
) {
1876 pr_err("%s: module sysfs not initialized\n", mod
->name
);
1881 kobj
= kset_find_obj(module_kset
, mod
->name
);
1883 pr_err("%s: module is already loaded\n", mod
->name
);
1889 mod
->mkobj
.mod
= mod
;
1891 memset(&mod
->mkobj
.kobj
, 0, sizeof(mod
->mkobj
.kobj
));
1892 mod
->mkobj
.kobj
.kset
= module_kset
;
1893 err
= kobject_init_and_add(&mod
->mkobj
.kobj
, &module_ktype
, NULL
,
1896 mod_kobject_put(mod
);
1898 /* delay uevent until full sysfs population */
1903 static int mod_sysfs_setup(struct module
*mod
,
1904 const struct load_info
*info
,
1905 struct kernel_param
*kparam
,
1906 unsigned int num_params
)
1910 err
= mod_sysfs_init(mod
);
1914 mod
->holders_dir
= kobject_create_and_add("holders", &mod
->mkobj
.kobj
);
1915 if (!mod
->holders_dir
) {
1920 err
= module_param_sysfs_setup(mod
, kparam
, num_params
);
1922 goto out_unreg_holders
;
1924 err
= module_add_modinfo_attrs(mod
);
1926 goto out_unreg_param
;
1928 err
= add_usage_links(mod
);
1930 goto out_unreg_modinfo_attrs
;
1932 add_sect_attrs(mod
, info
);
1933 add_notes_attrs(mod
, info
);
1935 kobject_uevent(&mod
->mkobj
.kobj
, KOBJ_ADD
);
1938 out_unreg_modinfo_attrs
:
1939 module_remove_modinfo_attrs(mod
, -1);
1941 module_param_sysfs_remove(mod
);
1943 kobject_put(mod
->holders_dir
);
1945 mod_kobject_put(mod
);
1950 static void mod_sysfs_fini(struct module
*mod
)
1952 remove_notes_attrs(mod
);
1953 remove_sect_attrs(mod
);
1954 mod_kobject_put(mod
);
1957 static void init_param_lock(struct module
*mod
)
1959 mutex_init(&mod
->param_lock
);
1961 #else /* !CONFIG_SYSFS */
1963 static int mod_sysfs_setup(struct module
*mod
,
1964 const struct load_info
*info
,
1965 struct kernel_param
*kparam
,
1966 unsigned int num_params
)
1971 static void mod_sysfs_fini(struct module
*mod
)
1975 static void module_remove_modinfo_attrs(struct module
*mod
, int end
)
1979 static void del_usage_links(struct module
*mod
)
1983 static void init_param_lock(struct module
*mod
)
1986 #endif /* CONFIG_SYSFS */
1988 static void mod_sysfs_teardown(struct module
*mod
)
1990 del_usage_links(mod
);
1991 module_remove_modinfo_attrs(mod
, -1);
1992 module_param_sysfs_remove(mod
);
1993 kobject_put(mod
->mkobj
.drivers_dir
);
1994 kobject_put(mod
->holders_dir
);
1995 mod_sysfs_fini(mod
);
1999 * LKM RO/NX protection: protect module's text/ro-data
2000 * from modification and any data from execution.
2002 * General layout of module is:
2003 * [text] [read-only-data] [ro-after-init] [writable data]
2004 * text_size -----^ ^ ^ ^
2005 * ro_size ------------------------| | |
2006 * ro_after_init_size -----------------------------| |
2007 * size -----------------------------------------------------------|
2009 * These values are always page-aligned (as is base)
2013 * Since some arches are moving towards PAGE_KERNEL module allocations instead
2014 * of PAGE_KERNEL_EXEC, keep frob_text() and module_enable_x() outside of the
2015 * CONFIG_STRICT_MODULE_RWX block below because they are needed regardless of
2016 * whether we are strict.
2018 #ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX
2019 static void frob_text(const struct module_layout
*layout
,
2020 int (*set_memory
)(unsigned long start
, int num_pages
))
2022 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
2023 BUG_ON((unsigned long)layout
->text_size
& (PAGE_SIZE
-1));
2024 set_memory((unsigned long)layout
->base
,
2025 layout
->text_size
>> PAGE_SHIFT
);
2028 static void module_enable_x(const struct module
*mod
)
2030 frob_text(&mod
->core_layout
, set_memory_x
);
2031 frob_text(&mod
->init_layout
, set_memory_x
);
2033 #else /* !CONFIG_ARCH_HAS_STRICT_MODULE_RWX */
2034 static void module_enable_x(const struct module
*mod
) { }
2035 #endif /* CONFIG_ARCH_HAS_STRICT_MODULE_RWX */
2037 #ifdef CONFIG_STRICT_MODULE_RWX
2038 static void frob_rodata(const struct module_layout
*layout
,
2039 int (*set_memory
)(unsigned long start
, int num_pages
))
2041 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
2042 BUG_ON((unsigned long)layout
->text_size
& (PAGE_SIZE
-1));
2043 BUG_ON((unsigned long)layout
->ro_size
& (PAGE_SIZE
-1));
2044 set_memory((unsigned long)layout
->base
+ layout
->text_size
,
2045 (layout
->ro_size
- layout
->text_size
) >> PAGE_SHIFT
);
2048 static void frob_ro_after_init(const struct module_layout
*layout
,
2049 int (*set_memory
)(unsigned long start
, int num_pages
))
2051 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
2052 BUG_ON((unsigned long)layout
->ro_size
& (PAGE_SIZE
-1));
2053 BUG_ON((unsigned long)layout
->ro_after_init_size
& (PAGE_SIZE
-1));
2054 set_memory((unsigned long)layout
->base
+ layout
->ro_size
,
2055 (layout
->ro_after_init_size
- layout
->ro_size
) >> PAGE_SHIFT
);
2058 static void frob_writable_data(const struct module_layout
*layout
,
2059 int (*set_memory
)(unsigned long start
, int num_pages
))
2061 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
2062 BUG_ON((unsigned long)layout
->ro_after_init_size
& (PAGE_SIZE
-1));
2063 BUG_ON((unsigned long)layout
->size
& (PAGE_SIZE
-1));
2064 set_memory((unsigned long)layout
->base
+ layout
->ro_after_init_size
,
2065 (layout
->size
- layout
->ro_after_init_size
) >> PAGE_SHIFT
);
2068 static void module_enable_ro(const struct module
*mod
, bool after_init
)
2070 if (!rodata_enabled
)
2073 set_vm_flush_reset_perms(mod
->core_layout
.base
);
2074 set_vm_flush_reset_perms(mod
->init_layout
.base
);
2075 frob_text(&mod
->core_layout
, set_memory_ro
);
2077 frob_rodata(&mod
->core_layout
, set_memory_ro
);
2078 frob_text(&mod
->init_layout
, set_memory_ro
);
2079 frob_rodata(&mod
->init_layout
, set_memory_ro
);
2082 frob_ro_after_init(&mod
->core_layout
, set_memory_ro
);
2085 static void module_enable_nx(const struct module
*mod
)
2087 frob_rodata(&mod
->core_layout
, set_memory_nx
);
2088 frob_ro_after_init(&mod
->core_layout
, set_memory_nx
);
2089 frob_writable_data(&mod
->core_layout
, set_memory_nx
);
2090 frob_rodata(&mod
->init_layout
, set_memory_nx
);
2091 frob_writable_data(&mod
->init_layout
, set_memory_nx
);
2094 static int module_enforce_rwx_sections(Elf_Ehdr
*hdr
, Elf_Shdr
*sechdrs
,
2095 char *secstrings
, struct module
*mod
)
2097 const unsigned long shf_wx
= SHF_WRITE
|SHF_EXECINSTR
;
2100 for (i
= 0; i
< hdr
->e_shnum
; i
++) {
2101 if ((sechdrs
[i
].sh_flags
& shf_wx
) == shf_wx
) {
2102 pr_err("%s: section %s (index %d) has invalid WRITE|EXEC flags\n",
2103 mod
->name
, secstrings
+ sechdrs
[i
].sh_name
, i
);
2111 #else /* !CONFIG_STRICT_MODULE_RWX */
2112 static void module_enable_nx(const struct module
*mod
) { }
2113 static void module_enable_ro(const struct module
*mod
, bool after_init
) {}
2114 static int module_enforce_rwx_sections(Elf_Ehdr
*hdr
, Elf_Shdr
*sechdrs
,
2115 char *secstrings
, struct module
*mod
)
2119 #endif /* CONFIG_STRICT_MODULE_RWX */
2121 #ifdef CONFIG_LIVEPATCH
2123 * Persist Elf information about a module. Copy the Elf header,
2124 * section header table, section string table, and symtab section
2125 * index from info to mod->klp_info.
2127 static int copy_module_elf(struct module
*mod
, struct load_info
*info
)
2129 unsigned int size
, symndx
;
2132 size
= sizeof(*mod
->klp_info
);
2133 mod
->klp_info
= kmalloc(size
, GFP_KERNEL
);
2134 if (mod
->klp_info
== NULL
)
2138 size
= sizeof(mod
->klp_info
->hdr
);
2139 memcpy(&mod
->klp_info
->hdr
, info
->hdr
, size
);
2141 /* Elf section header table */
2142 size
= sizeof(*info
->sechdrs
) * info
->hdr
->e_shnum
;
2143 mod
->klp_info
->sechdrs
= kmemdup(info
->sechdrs
, size
, GFP_KERNEL
);
2144 if (mod
->klp_info
->sechdrs
== NULL
) {
2149 /* Elf section name string table */
2150 size
= info
->sechdrs
[info
->hdr
->e_shstrndx
].sh_size
;
2151 mod
->klp_info
->secstrings
= kmemdup(info
->secstrings
, size
, GFP_KERNEL
);
2152 if (mod
->klp_info
->secstrings
== NULL
) {
2157 /* Elf symbol section index */
2158 symndx
= info
->index
.sym
;
2159 mod
->klp_info
->symndx
= symndx
;
2162 * For livepatch modules, core_kallsyms.symtab is a complete
2163 * copy of the original symbol table. Adjust sh_addr to point
2164 * to core_kallsyms.symtab since the copy of the symtab in module
2165 * init memory is freed at the end of do_init_module().
2167 mod
->klp_info
->sechdrs
[symndx
].sh_addr
= \
2168 (unsigned long) mod
->core_kallsyms
.symtab
;
2173 kfree(mod
->klp_info
->sechdrs
);
2175 kfree(mod
->klp_info
);
2179 static void free_module_elf(struct module
*mod
)
2181 kfree(mod
->klp_info
->sechdrs
);
2182 kfree(mod
->klp_info
->secstrings
);
2183 kfree(mod
->klp_info
);
2185 #else /* !CONFIG_LIVEPATCH */
2186 static int copy_module_elf(struct module
*mod
, struct load_info
*info
)
2191 static void free_module_elf(struct module
*mod
)
2194 #endif /* CONFIG_LIVEPATCH */
2196 void __weak
module_memfree(void *module_region
)
2199 * This memory may be RO, and freeing RO memory in an interrupt is not
2200 * supported by vmalloc.
2202 WARN_ON(in_interrupt());
2203 vfree(module_region
);
2206 void __weak
module_arch_cleanup(struct module
*mod
)
2210 void __weak
module_arch_freeing_init(struct module
*mod
)
2214 /* Free a module, remove from lists, etc. */
2215 static void free_module(struct module
*mod
)
2217 trace_module_free(mod
);
2219 mod_sysfs_teardown(mod
);
2221 /* We leave it in list to prevent duplicate loads, but make sure
2222 * that noone uses it while it's being deconstructed. */
2223 mutex_lock(&module_mutex
);
2224 mod
->state
= MODULE_STATE_UNFORMED
;
2225 mutex_unlock(&module_mutex
);
2227 /* Remove dynamic debug info */
2228 ddebug_remove_module(mod
->name
);
2230 /* Arch-specific cleanup. */
2231 module_arch_cleanup(mod
);
2233 /* Module unload stuff */
2234 module_unload_free(mod
);
2236 /* Free any allocated parameters. */
2237 destroy_params(mod
->kp
, mod
->num_kp
);
2239 if (is_livepatch_module(mod
))
2240 free_module_elf(mod
);
2242 /* Now we can delete it from the lists */
2243 mutex_lock(&module_mutex
);
2244 /* Unlink carefully: kallsyms could be walking list. */
2245 list_del_rcu(&mod
->list
);
2246 mod_tree_remove(mod
);
2247 /* Remove this module from bug list, this uses list_del_rcu */
2248 module_bug_cleanup(mod
);
2249 /* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */
2251 mutex_unlock(&module_mutex
);
2253 /* This may be empty, but that's OK */
2254 module_arch_freeing_init(mod
);
2255 module_memfree(mod
->init_layout
.base
);
2257 percpu_modfree(mod
);
2259 /* Free lock-classes; relies on the preceding sync_rcu(). */
2260 lockdep_free_key_range(mod
->core_layout
.base
, mod
->core_layout
.size
);
2262 /* Finally, free the core (containing the module structure) */
2263 module_memfree(mod
->core_layout
.base
);
2266 void *__symbol_get(const char *symbol
)
2268 struct module
*owner
;
2269 const struct kernel_symbol
*sym
;
2272 sym
= find_symbol(symbol
, &owner
, NULL
, NULL
, true, true);
2273 if (sym
&& strong_try_module_get(owner
))
2277 return sym
? (void *)kernel_symbol_value(sym
) : NULL
;
2279 EXPORT_SYMBOL_GPL(__symbol_get
);
2282 * Ensure that an exported symbol [global namespace] does not already exist
2283 * in the kernel or in some other module's exported symbol table.
2285 * You must hold the module_mutex.
2287 static int verify_exported_symbols(struct module
*mod
)
2290 struct module
*owner
;
2291 const struct kernel_symbol
*s
;
2293 const struct kernel_symbol
*sym
;
2296 { mod
->syms
, mod
->num_syms
},
2297 { mod
->gpl_syms
, mod
->num_gpl_syms
},
2298 { mod
->gpl_future_syms
, mod
->num_gpl_future_syms
},
2299 #ifdef CONFIG_UNUSED_SYMBOLS
2300 { mod
->unused_syms
, mod
->num_unused_syms
},
2301 { mod
->unused_gpl_syms
, mod
->num_unused_gpl_syms
},
2305 for (i
= 0; i
< ARRAY_SIZE(arr
); i
++) {
2306 for (s
= arr
[i
].sym
; s
< arr
[i
].sym
+ arr
[i
].num
; s
++) {
2307 if (find_symbol(kernel_symbol_name(s
), &owner
, NULL
,
2308 NULL
, true, false)) {
2309 pr_err("%s: exports duplicate symbol %s"
2311 mod
->name
, kernel_symbol_name(s
),
2312 module_name(owner
));
2320 /* Change all symbols so that st_value encodes the pointer directly. */
2321 static int simplify_symbols(struct module
*mod
, const struct load_info
*info
)
2323 Elf_Shdr
*symsec
= &info
->sechdrs
[info
->index
.sym
];
2324 Elf_Sym
*sym
= (void *)symsec
->sh_addr
;
2325 unsigned long secbase
;
2328 const struct kernel_symbol
*ksym
;
2330 for (i
= 1; i
< symsec
->sh_size
/ sizeof(Elf_Sym
); i
++) {
2331 const char *name
= info
->strtab
+ sym
[i
].st_name
;
2333 switch (sym
[i
].st_shndx
) {
2335 /* Ignore common symbols */
2336 if (!strncmp(name
, "__gnu_lto", 9))
2339 /* We compiled with -fno-common. These are not
2340 supposed to happen. */
2341 pr_debug("Common symbol: %s\n", name
);
2342 pr_warn("%s: please compile with -fno-common\n",
2348 /* Don't need to do anything */
2349 pr_debug("Absolute symbol: 0x%08lx\n",
2350 (long)sym
[i
].st_value
);
2354 /* Livepatch symbols are resolved by livepatch */
2358 ksym
= resolve_symbol_wait(mod
, info
, name
);
2359 /* Ok if resolved. */
2360 if (ksym
&& !IS_ERR(ksym
)) {
2361 sym
[i
].st_value
= kernel_symbol_value(ksym
);
2366 if (!ksym
&& ELF_ST_BIND(sym
[i
].st_info
) == STB_WEAK
)
2369 ret
= PTR_ERR(ksym
) ?: -ENOENT
;
2370 pr_warn("%s: Unknown symbol %s (err %d)\n",
2371 mod
->name
, name
, ret
);
2375 /* Divert to percpu allocation if a percpu var. */
2376 if (sym
[i
].st_shndx
== info
->index
.pcpu
)
2377 secbase
= (unsigned long)mod_percpu(mod
);
2379 secbase
= info
->sechdrs
[sym
[i
].st_shndx
].sh_addr
;
2380 sym
[i
].st_value
+= secbase
;
2388 static int apply_relocations(struct module
*mod
, const struct load_info
*info
)
2393 /* Now do relocations. */
2394 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2395 unsigned int infosec
= info
->sechdrs
[i
].sh_info
;
2397 /* Not a valid relocation section? */
2398 if (infosec
>= info
->hdr
->e_shnum
)
2401 /* Don't bother with non-allocated sections */
2402 if (!(info
->sechdrs
[infosec
].sh_flags
& SHF_ALLOC
))
2405 if (info
->sechdrs
[i
].sh_flags
& SHF_RELA_LIVEPATCH
)
2406 err
= klp_apply_section_relocs(mod
, info
->sechdrs
,
2411 else if (info
->sechdrs
[i
].sh_type
== SHT_REL
)
2412 err
= apply_relocate(info
->sechdrs
, info
->strtab
,
2413 info
->index
.sym
, i
, mod
);
2414 else if (info
->sechdrs
[i
].sh_type
== SHT_RELA
)
2415 err
= apply_relocate_add(info
->sechdrs
, info
->strtab
,
2416 info
->index
.sym
, i
, mod
);
2423 /* Additional bytes needed by arch in front of individual sections */
2424 unsigned int __weak
arch_mod_section_prepend(struct module
*mod
,
2425 unsigned int section
)
2427 /* default implementation just returns zero */
2431 /* Update size with this section: return offset. */
2432 static long get_offset(struct module
*mod
, unsigned int *size
,
2433 Elf_Shdr
*sechdr
, unsigned int section
)
2437 *size
+= arch_mod_section_prepend(mod
, section
);
2438 ret
= ALIGN(*size
, sechdr
->sh_addralign
?: 1);
2439 *size
= ret
+ sechdr
->sh_size
;
2443 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
2444 might -- code, read-only data, read-write data, small data. Tally
2445 sizes, and place the offsets into sh_entsize fields: high bit means it
2447 static void layout_sections(struct module
*mod
, struct load_info
*info
)
2449 static unsigned long const masks
[][2] = {
2450 /* NOTE: all executable code must be the first section
2451 * in this array; otherwise modify the text_size
2452 * finder in the two loops below */
2453 { SHF_EXECINSTR
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2454 { SHF_ALLOC
, SHF_WRITE
| ARCH_SHF_SMALL
},
2455 { SHF_RO_AFTER_INIT
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2456 { SHF_WRITE
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2457 { ARCH_SHF_SMALL
| SHF_ALLOC
, 0 }
2461 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
2462 info
->sechdrs
[i
].sh_entsize
= ~0UL;
2464 pr_debug("Core section allocation order:\n");
2465 for (m
= 0; m
< ARRAY_SIZE(masks
); ++m
) {
2466 for (i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
2467 Elf_Shdr
*s
= &info
->sechdrs
[i
];
2468 const char *sname
= info
->secstrings
+ s
->sh_name
;
2470 if ((s
->sh_flags
& masks
[m
][0]) != masks
[m
][0]
2471 || (s
->sh_flags
& masks
[m
][1])
2472 || s
->sh_entsize
!= ~0UL
2473 || module_init_section(sname
))
2475 s
->sh_entsize
= get_offset(mod
, &mod
->core_layout
.size
, s
, i
);
2476 pr_debug("\t%s\n", sname
);
2479 case 0: /* executable */
2480 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2481 mod
->core_layout
.text_size
= mod
->core_layout
.size
;
2483 case 1: /* RO: text and ro-data */
2484 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2485 mod
->core_layout
.ro_size
= mod
->core_layout
.size
;
2487 case 2: /* RO after init */
2488 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2489 mod
->core_layout
.ro_after_init_size
= mod
->core_layout
.size
;
2491 case 4: /* whole core */
2492 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2497 pr_debug("Init section allocation order:\n");
2498 for (m
= 0; m
< ARRAY_SIZE(masks
); ++m
) {
2499 for (i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
2500 Elf_Shdr
*s
= &info
->sechdrs
[i
];
2501 const char *sname
= info
->secstrings
+ s
->sh_name
;
2503 if ((s
->sh_flags
& masks
[m
][0]) != masks
[m
][0]
2504 || (s
->sh_flags
& masks
[m
][1])
2505 || s
->sh_entsize
!= ~0UL
2506 || !module_init_section(sname
))
2508 s
->sh_entsize
= (get_offset(mod
, &mod
->init_layout
.size
, s
, i
)
2509 | INIT_OFFSET_MASK
);
2510 pr_debug("\t%s\n", sname
);
2513 case 0: /* executable */
2514 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2515 mod
->init_layout
.text_size
= mod
->init_layout
.size
;
2517 case 1: /* RO: text and ro-data */
2518 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2519 mod
->init_layout
.ro_size
= mod
->init_layout
.size
;
2523 * RO after init doesn't apply to init_layout (only
2524 * core_layout), so it just takes the value of ro_size.
2526 mod
->init_layout
.ro_after_init_size
= mod
->init_layout
.ro_size
;
2528 case 4: /* whole init */
2529 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2535 static void set_license(struct module
*mod
, const char *license
)
2538 license
= "unspecified";
2540 if (!license_is_gpl_compatible(license
)) {
2541 if (!test_taint(TAINT_PROPRIETARY_MODULE
))
2542 pr_warn("%s: module license '%s' taints kernel.\n",
2543 mod
->name
, license
);
2544 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
2545 LOCKDEP_NOW_UNRELIABLE
);
2549 /* Parse tag=value strings from .modinfo section */
2550 static char *next_string(char *string
, unsigned long *secsize
)
2552 /* Skip non-zero chars */
2555 if ((*secsize
)-- <= 1)
2559 /* Skip any zero padding. */
2560 while (!string
[0]) {
2562 if ((*secsize
)-- <= 1)
2568 static char *get_next_modinfo(const struct load_info
*info
, const char *tag
,
2572 unsigned int taglen
= strlen(tag
);
2573 Elf_Shdr
*infosec
= &info
->sechdrs
[info
->index
.info
];
2574 unsigned long size
= infosec
->sh_size
;
2577 * get_modinfo() calls made before rewrite_section_headers()
2578 * must use sh_offset, as sh_addr isn't set!
2580 char *modinfo
= (char *)info
->hdr
+ infosec
->sh_offset
;
2583 size
-= prev
- modinfo
;
2584 modinfo
= next_string(prev
, &size
);
2587 for (p
= modinfo
; p
; p
= next_string(p
, &size
)) {
2588 if (strncmp(p
, tag
, taglen
) == 0 && p
[taglen
] == '=')
2589 return p
+ taglen
+ 1;
2594 static char *get_modinfo(const struct load_info
*info
, const char *tag
)
2596 return get_next_modinfo(info
, tag
, NULL
);
2599 static void setup_modinfo(struct module
*mod
, struct load_info
*info
)
2601 struct module_attribute
*attr
;
2604 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
2606 attr
->setup(mod
, get_modinfo(info
, attr
->attr
.name
));
2610 static void free_modinfo(struct module
*mod
)
2612 struct module_attribute
*attr
;
2615 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
2621 #ifdef CONFIG_KALLSYMS
2623 /* Lookup exported symbol in given range of kernel_symbols */
2624 static const struct kernel_symbol
*lookup_exported_symbol(const char *name
,
2625 const struct kernel_symbol
*start
,
2626 const struct kernel_symbol
*stop
)
2628 return bsearch(name
, start
, stop
- start
,
2629 sizeof(struct kernel_symbol
), cmp_name
);
2632 static int is_exported(const char *name
, unsigned long value
,
2633 const struct module
*mod
)
2635 const struct kernel_symbol
*ks
;
2637 ks
= lookup_exported_symbol(name
, __start___ksymtab
, __stop___ksymtab
);
2639 ks
= lookup_exported_symbol(name
, mod
->syms
, mod
->syms
+ mod
->num_syms
);
2641 return ks
!= NULL
&& kernel_symbol_value(ks
) == value
;
2645 static char elf_type(const Elf_Sym
*sym
, const struct load_info
*info
)
2647 const Elf_Shdr
*sechdrs
= info
->sechdrs
;
2649 if (ELF_ST_BIND(sym
->st_info
) == STB_WEAK
) {
2650 if (ELF_ST_TYPE(sym
->st_info
) == STT_OBJECT
)
2655 if (sym
->st_shndx
== SHN_UNDEF
)
2657 if (sym
->st_shndx
== SHN_ABS
|| sym
->st_shndx
== info
->index
.pcpu
)
2659 if (sym
->st_shndx
>= SHN_LORESERVE
)
2661 if (sechdrs
[sym
->st_shndx
].sh_flags
& SHF_EXECINSTR
)
2663 if (sechdrs
[sym
->st_shndx
].sh_flags
& SHF_ALLOC
2664 && sechdrs
[sym
->st_shndx
].sh_type
!= SHT_NOBITS
) {
2665 if (!(sechdrs
[sym
->st_shndx
].sh_flags
& SHF_WRITE
))
2667 else if (sechdrs
[sym
->st_shndx
].sh_flags
& ARCH_SHF_SMALL
)
2672 if (sechdrs
[sym
->st_shndx
].sh_type
== SHT_NOBITS
) {
2673 if (sechdrs
[sym
->st_shndx
].sh_flags
& ARCH_SHF_SMALL
)
2678 if (strstarts(info
->secstrings
+ sechdrs
[sym
->st_shndx
].sh_name
,
2685 static bool is_core_symbol(const Elf_Sym
*src
, const Elf_Shdr
*sechdrs
,
2686 unsigned int shnum
, unsigned int pcpundx
)
2688 const Elf_Shdr
*sec
;
2690 if (src
->st_shndx
== SHN_UNDEF
2691 || src
->st_shndx
>= shnum
2695 #ifdef CONFIG_KALLSYMS_ALL
2696 if (src
->st_shndx
== pcpundx
)
2700 sec
= sechdrs
+ src
->st_shndx
;
2701 if (!(sec
->sh_flags
& SHF_ALLOC
)
2702 #ifndef CONFIG_KALLSYMS_ALL
2703 || !(sec
->sh_flags
& SHF_EXECINSTR
)
2705 || (sec
->sh_entsize
& INIT_OFFSET_MASK
))
2712 * We only allocate and copy the strings needed by the parts of symtab
2713 * we keep. This is simple, but has the effect of making multiple
2714 * copies of duplicates. We could be more sophisticated, see
2715 * linux-kernel thread starting with
2716 * <73defb5e4bca04a6431392cc341112b1@localhost>.
2718 static void layout_symtab(struct module
*mod
, struct load_info
*info
)
2720 Elf_Shdr
*symsect
= info
->sechdrs
+ info
->index
.sym
;
2721 Elf_Shdr
*strsect
= info
->sechdrs
+ info
->index
.str
;
2723 unsigned int i
, nsrc
, ndst
, strtab_size
= 0;
2725 /* Put symbol section at end of init part of module. */
2726 symsect
->sh_flags
|= SHF_ALLOC
;
2727 symsect
->sh_entsize
= get_offset(mod
, &mod
->init_layout
.size
, symsect
,
2728 info
->index
.sym
) | INIT_OFFSET_MASK
;
2729 pr_debug("\t%s\n", info
->secstrings
+ symsect
->sh_name
);
2731 src
= (void *)info
->hdr
+ symsect
->sh_offset
;
2732 nsrc
= symsect
->sh_size
/ sizeof(*src
);
2734 /* Compute total space required for the core symbols' strtab. */
2735 for (ndst
= i
= 0; i
< nsrc
; i
++) {
2736 if (i
== 0 || is_livepatch_module(mod
) ||
2737 is_core_symbol(src
+i
, info
->sechdrs
, info
->hdr
->e_shnum
,
2738 info
->index
.pcpu
)) {
2739 strtab_size
+= strlen(&info
->strtab
[src
[i
].st_name
])+1;
2744 /* Append room for core symbols at end of core part. */
2745 info
->symoffs
= ALIGN(mod
->core_layout
.size
, symsect
->sh_addralign
?: 1);
2746 info
->stroffs
= mod
->core_layout
.size
= info
->symoffs
+ ndst
* sizeof(Elf_Sym
);
2747 mod
->core_layout
.size
+= strtab_size
;
2748 info
->core_typeoffs
= mod
->core_layout
.size
;
2749 mod
->core_layout
.size
+= ndst
* sizeof(char);
2750 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2752 /* Put string table section at end of init part of module. */
2753 strsect
->sh_flags
|= SHF_ALLOC
;
2754 strsect
->sh_entsize
= get_offset(mod
, &mod
->init_layout
.size
, strsect
,
2755 info
->index
.str
) | INIT_OFFSET_MASK
;
2756 pr_debug("\t%s\n", info
->secstrings
+ strsect
->sh_name
);
2758 /* We'll tack temporary mod_kallsyms on the end. */
2759 mod
->init_layout
.size
= ALIGN(mod
->init_layout
.size
,
2760 __alignof__(struct mod_kallsyms
));
2761 info
->mod_kallsyms_init_off
= mod
->init_layout
.size
;
2762 mod
->init_layout
.size
+= sizeof(struct mod_kallsyms
);
2763 info
->init_typeoffs
= mod
->init_layout
.size
;
2764 mod
->init_layout
.size
+= nsrc
* sizeof(char);
2765 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2769 * We use the full symtab and strtab which layout_symtab arranged to
2770 * be appended to the init section. Later we switch to the cut-down
2773 static void add_kallsyms(struct module
*mod
, const struct load_info
*info
)
2775 unsigned int i
, ndst
;
2779 Elf_Shdr
*symsec
= &info
->sechdrs
[info
->index
.sym
];
2781 /* Set up to point into init section. */
2782 mod
->kallsyms
= mod
->init_layout
.base
+ info
->mod_kallsyms_init_off
;
2784 mod
->kallsyms
->symtab
= (void *)symsec
->sh_addr
;
2785 mod
->kallsyms
->num_symtab
= symsec
->sh_size
/ sizeof(Elf_Sym
);
2786 /* Make sure we get permanent strtab: don't use info->strtab. */
2787 mod
->kallsyms
->strtab
= (void *)info
->sechdrs
[info
->index
.str
].sh_addr
;
2788 mod
->kallsyms
->typetab
= mod
->init_layout
.base
+ info
->init_typeoffs
;
2791 * Now populate the cut down core kallsyms for after init
2792 * and set types up while we still have access to sections.
2794 mod
->core_kallsyms
.symtab
= dst
= mod
->core_layout
.base
+ info
->symoffs
;
2795 mod
->core_kallsyms
.strtab
= s
= mod
->core_layout
.base
+ info
->stroffs
;
2796 mod
->core_kallsyms
.typetab
= mod
->core_layout
.base
+ info
->core_typeoffs
;
2797 src
= mod
->kallsyms
->symtab
;
2798 for (ndst
= i
= 0; i
< mod
->kallsyms
->num_symtab
; i
++) {
2799 mod
->kallsyms
->typetab
[i
] = elf_type(src
+ i
, info
);
2800 if (i
== 0 || is_livepatch_module(mod
) ||
2801 is_core_symbol(src
+i
, info
->sechdrs
, info
->hdr
->e_shnum
,
2802 info
->index
.pcpu
)) {
2803 mod
->core_kallsyms
.typetab
[ndst
] =
2804 mod
->kallsyms
->typetab
[i
];
2806 dst
[ndst
++].st_name
= s
- mod
->core_kallsyms
.strtab
;
2807 s
+= strlcpy(s
, &mod
->kallsyms
->strtab
[src
[i
].st_name
],
2811 mod
->core_kallsyms
.num_symtab
= ndst
;
2814 static inline void layout_symtab(struct module
*mod
, struct load_info
*info
)
2818 static void add_kallsyms(struct module
*mod
, const struct load_info
*info
)
2821 #endif /* CONFIG_KALLSYMS */
2823 static void dynamic_debug_setup(struct module
*mod
, struct _ddebug
*debug
, unsigned int num
)
2827 ddebug_add_module(debug
, num
, mod
->name
);
2830 static void dynamic_debug_remove(struct module
*mod
, struct _ddebug
*debug
)
2833 ddebug_remove_module(mod
->name
);
2836 void * __weak
module_alloc(unsigned long size
)
2838 return __vmalloc_node_range(size
, 1, VMALLOC_START
, VMALLOC_END
,
2839 GFP_KERNEL
, PAGE_KERNEL_EXEC
, VM_FLUSH_RESET_PERMS
,
2840 NUMA_NO_NODE
, __builtin_return_address(0));
2843 bool __weak
module_init_section(const char *name
)
2845 return strstarts(name
, ".init");
2848 bool __weak
module_exit_section(const char *name
)
2850 return strstarts(name
, ".exit");
2853 #ifdef CONFIG_DEBUG_KMEMLEAK
2854 static void kmemleak_load_module(const struct module
*mod
,
2855 const struct load_info
*info
)
2859 /* only scan the sections containing data */
2860 kmemleak_scan_area(mod
, sizeof(struct module
), GFP_KERNEL
);
2862 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2863 /* Scan all writable sections that's not executable */
2864 if (!(info
->sechdrs
[i
].sh_flags
& SHF_ALLOC
) ||
2865 !(info
->sechdrs
[i
].sh_flags
& SHF_WRITE
) ||
2866 (info
->sechdrs
[i
].sh_flags
& SHF_EXECINSTR
))
2869 kmemleak_scan_area((void *)info
->sechdrs
[i
].sh_addr
,
2870 info
->sechdrs
[i
].sh_size
, GFP_KERNEL
);
2874 static inline void kmemleak_load_module(const struct module
*mod
,
2875 const struct load_info
*info
)
2880 #ifdef CONFIG_MODULE_SIG
2881 static int module_sig_check(struct load_info
*info
, int flags
)
2884 const unsigned long markerlen
= sizeof(MODULE_SIG_STRING
) - 1;
2886 const void *mod
= info
->hdr
;
2889 * Require flags == 0, as a module with version information
2890 * removed is no longer the module that was signed
2893 info
->len
> markerlen
&&
2894 memcmp(mod
+ info
->len
- markerlen
, MODULE_SIG_STRING
, markerlen
) == 0) {
2895 /* We truncate the module to discard the signature */
2896 info
->len
-= markerlen
;
2897 err
= mod_verify_sig(mod
, info
);
2902 info
->sig_ok
= true;
2905 /* We don't permit modules to be loaded into trusted kernels
2906 * without a valid signature on them, but if we're not
2907 * enforcing, certain errors are non-fatal.
2910 reason
= "Loading of unsigned module";
2913 reason
= "Loading of module with unsupported crypto";
2916 reason
= "Loading of module with unavailable key";
2918 if (is_module_sig_enforced()) {
2919 pr_notice("%s: %s is rejected\n", info
->name
, reason
);
2920 return -EKEYREJECTED
;
2923 return security_locked_down(LOCKDOWN_MODULE_SIGNATURE
);
2925 /* All other errors are fatal, including nomem, unparseable
2926 * signatures and signature check failures - even if signatures
2933 #else /* !CONFIG_MODULE_SIG */
2934 static int module_sig_check(struct load_info
*info
, int flags
)
2938 #endif /* !CONFIG_MODULE_SIG */
2940 /* Sanity checks against invalid binaries, wrong arch, weird elf version. */
2941 static int elf_header_check(struct load_info
*info
)
2943 if (info
->len
< sizeof(*(info
->hdr
)))
2946 if (memcmp(info
->hdr
->e_ident
, ELFMAG
, SELFMAG
) != 0
2947 || info
->hdr
->e_type
!= ET_REL
2948 || !elf_check_arch(info
->hdr
)
2949 || info
->hdr
->e_shentsize
!= sizeof(Elf_Shdr
))
2952 if (info
->hdr
->e_shoff
>= info
->len
2953 || (info
->hdr
->e_shnum
* sizeof(Elf_Shdr
) >
2954 info
->len
- info
->hdr
->e_shoff
))
2960 #define COPY_CHUNK_SIZE (16*PAGE_SIZE)
2962 static int copy_chunked_from_user(void *dst
, const void __user
*usrc
, unsigned long len
)
2965 unsigned long n
= min(len
, COPY_CHUNK_SIZE
);
2967 if (copy_from_user(dst
, usrc
, n
) != 0)
2977 #ifdef CONFIG_LIVEPATCH
2978 static int check_modinfo_livepatch(struct module
*mod
, struct load_info
*info
)
2980 if (get_modinfo(info
, "livepatch")) {
2982 add_taint_module(mod
, TAINT_LIVEPATCH
, LOCKDEP_STILL_OK
);
2983 pr_notice_once("%s: tainting kernel with TAINT_LIVEPATCH\n",
2989 #else /* !CONFIG_LIVEPATCH */
2990 static int check_modinfo_livepatch(struct module
*mod
, struct load_info
*info
)
2992 if (get_modinfo(info
, "livepatch")) {
2993 pr_err("%s: module is marked as livepatch module, but livepatch support is disabled",
3000 #endif /* CONFIG_LIVEPATCH */
3002 static void check_modinfo_retpoline(struct module
*mod
, struct load_info
*info
)
3004 if (retpoline_module_ok(get_modinfo(info
, "retpoline")))
3007 pr_warn("%s: loading module not compiled with retpoline compiler.\n",
3011 /* Sets info->hdr and info->len. */
3012 static int copy_module_from_user(const void __user
*umod
, unsigned long len
,
3013 struct load_info
*info
)
3018 if (info
->len
< sizeof(*(info
->hdr
)))
3021 err
= security_kernel_load_data(LOADING_MODULE
, true);
3025 /* Suck in entire file: we'll want most of it. */
3026 info
->hdr
= __vmalloc(info
->len
, GFP_KERNEL
| __GFP_NOWARN
);
3030 if (copy_chunked_from_user(info
->hdr
, umod
, info
->len
) != 0) {
3035 err
= security_kernel_post_load_data((char *)info
->hdr
, info
->len
,
3036 LOADING_MODULE
, "init_module");
3044 static void free_copy(struct load_info
*info
)
3049 static int rewrite_section_headers(struct load_info
*info
, int flags
)
3053 /* This should always be true, but let's be sure. */
3054 info
->sechdrs
[0].sh_addr
= 0;
3056 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
3057 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
3058 if (shdr
->sh_type
!= SHT_NOBITS
3059 && info
->len
< shdr
->sh_offset
+ shdr
->sh_size
) {
3060 pr_err("Module len %lu truncated\n", info
->len
);
3064 /* Mark all sections sh_addr with their address in the
3066 shdr
->sh_addr
= (size_t)info
->hdr
+ shdr
->sh_offset
;
3068 #ifndef CONFIG_MODULE_UNLOAD
3069 /* Don't load .exit sections */
3070 if (module_exit_section(info
->secstrings
+shdr
->sh_name
))
3071 shdr
->sh_flags
&= ~(unsigned long)SHF_ALLOC
;
3075 /* Track but don't keep modinfo and version sections. */
3076 info
->sechdrs
[info
->index
.vers
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
3077 info
->sechdrs
[info
->index
.info
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
3083 * Set up our basic convenience variables (pointers to section headers,
3084 * search for module section index etc), and do some basic section
3087 * Set info->mod to the temporary copy of the module in info->hdr. The final one
3088 * will be allocated in move_module().
3090 static int setup_load_info(struct load_info
*info
, int flags
)
3094 /* Set up the convenience variables */
3095 info
->sechdrs
= (void *)info
->hdr
+ info
->hdr
->e_shoff
;
3096 info
->secstrings
= (void *)info
->hdr
3097 + info
->sechdrs
[info
->hdr
->e_shstrndx
].sh_offset
;
3099 /* Try to find a name early so we can log errors with a module name */
3100 info
->index
.info
= find_sec(info
, ".modinfo");
3101 if (info
->index
.info
)
3102 info
->name
= get_modinfo(info
, "name");
3104 /* Find internal symbols and strings. */
3105 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
3106 if (info
->sechdrs
[i
].sh_type
== SHT_SYMTAB
) {
3107 info
->index
.sym
= i
;
3108 info
->index
.str
= info
->sechdrs
[i
].sh_link
;
3109 info
->strtab
= (char *)info
->hdr
3110 + info
->sechdrs
[info
->index
.str
].sh_offset
;
3115 if (info
->index
.sym
== 0) {
3116 pr_warn("%s: module has no symbols (stripped?)\n",
3117 info
->name
?: "(missing .modinfo section or name field)");
3121 info
->index
.mod
= find_sec(info
, ".gnu.linkonce.this_module");
3122 if (!info
->index
.mod
) {
3123 pr_warn("%s: No module found in object\n",
3124 info
->name
?: "(missing .modinfo section or name field)");
3127 /* This is temporary: point mod into copy of data. */
3128 info
->mod
= (void *)info
->hdr
+ info
->sechdrs
[info
->index
.mod
].sh_offset
;
3131 * If we didn't load the .modinfo 'name' field earlier, fall back to
3132 * on-disk struct mod 'name' field.
3135 info
->name
= info
->mod
->name
;
3137 if (flags
& MODULE_INIT_IGNORE_MODVERSIONS
)
3138 info
->index
.vers
= 0; /* Pretend no __versions section! */
3140 info
->index
.vers
= find_sec(info
, "__versions");
3142 info
->index
.pcpu
= find_pcpusec(info
);
3147 static int check_modinfo(struct module
*mod
, struct load_info
*info
, int flags
)
3149 const char *modmagic
= get_modinfo(info
, "vermagic");
3152 if (flags
& MODULE_INIT_IGNORE_VERMAGIC
)
3155 /* This is allowed: modprobe --force will invalidate it. */
3157 err
= try_to_force_load(mod
, "bad vermagic");
3160 } else if (!same_magic(modmagic
, vermagic
, info
->index
.vers
)) {
3161 pr_err("%s: version magic '%s' should be '%s'\n",
3162 info
->name
, modmagic
, vermagic
);
3166 if (!get_modinfo(info
, "intree")) {
3167 if (!test_taint(TAINT_OOT_MODULE
))
3168 pr_warn("%s: loading out-of-tree module taints kernel.\n",
3170 add_taint_module(mod
, TAINT_OOT_MODULE
, LOCKDEP_STILL_OK
);
3173 check_modinfo_retpoline(mod
, info
);
3175 if (get_modinfo(info
, "staging")) {
3176 add_taint_module(mod
, TAINT_CRAP
, LOCKDEP_STILL_OK
);
3177 pr_warn("%s: module is from the staging directory, the quality "
3178 "is unknown, you have been warned.\n", mod
->name
);
3181 err
= check_modinfo_livepatch(mod
, info
);
3185 /* Set up license info based on the info section */
3186 set_license(mod
, get_modinfo(info
, "license"));
3191 static int find_module_sections(struct module
*mod
, struct load_info
*info
)
3193 mod
->kp
= section_objs(info
, "__param",
3194 sizeof(*mod
->kp
), &mod
->num_kp
);
3195 mod
->syms
= section_objs(info
, "__ksymtab",
3196 sizeof(*mod
->syms
), &mod
->num_syms
);
3197 mod
->crcs
= section_addr(info
, "__kcrctab");
3198 mod
->gpl_syms
= section_objs(info
, "__ksymtab_gpl",
3199 sizeof(*mod
->gpl_syms
),
3200 &mod
->num_gpl_syms
);
3201 mod
->gpl_crcs
= section_addr(info
, "__kcrctab_gpl");
3202 mod
->gpl_future_syms
= section_objs(info
,
3203 "__ksymtab_gpl_future",
3204 sizeof(*mod
->gpl_future_syms
),
3205 &mod
->num_gpl_future_syms
);
3206 mod
->gpl_future_crcs
= section_addr(info
, "__kcrctab_gpl_future");
3208 #ifdef CONFIG_UNUSED_SYMBOLS
3209 mod
->unused_syms
= section_objs(info
, "__ksymtab_unused",
3210 sizeof(*mod
->unused_syms
),
3211 &mod
->num_unused_syms
);
3212 mod
->unused_crcs
= section_addr(info
, "__kcrctab_unused");
3213 mod
->unused_gpl_syms
= section_objs(info
, "__ksymtab_unused_gpl",
3214 sizeof(*mod
->unused_gpl_syms
),
3215 &mod
->num_unused_gpl_syms
);
3216 mod
->unused_gpl_crcs
= section_addr(info
, "__kcrctab_unused_gpl");
3218 #ifdef CONFIG_CONSTRUCTORS
3219 mod
->ctors
= section_objs(info
, ".ctors",
3220 sizeof(*mod
->ctors
), &mod
->num_ctors
);
3222 mod
->ctors
= section_objs(info
, ".init_array",
3223 sizeof(*mod
->ctors
), &mod
->num_ctors
);
3224 else if (find_sec(info
, ".init_array")) {
3226 * This shouldn't happen with same compiler and binutils
3227 * building all parts of the module.
3229 pr_warn("%s: has both .ctors and .init_array.\n",
3235 mod
->noinstr_text_start
= section_objs(info
, ".noinstr.text", 1,
3236 &mod
->noinstr_text_size
);
3238 #ifdef CONFIG_TRACEPOINTS
3239 mod
->tracepoints_ptrs
= section_objs(info
, "__tracepoints_ptrs",
3240 sizeof(*mod
->tracepoints_ptrs
),
3241 &mod
->num_tracepoints
);
3243 #ifdef CONFIG_TREE_SRCU
3244 mod
->srcu_struct_ptrs
= section_objs(info
, "___srcu_struct_ptrs",
3245 sizeof(*mod
->srcu_struct_ptrs
),
3246 &mod
->num_srcu_structs
);
3248 #ifdef CONFIG_BPF_EVENTS
3249 mod
->bpf_raw_events
= section_objs(info
, "__bpf_raw_tp_map",
3250 sizeof(*mod
->bpf_raw_events
),
3251 &mod
->num_bpf_raw_events
);
3253 #ifdef CONFIG_JUMP_LABEL
3254 mod
->jump_entries
= section_objs(info
, "__jump_table",
3255 sizeof(*mod
->jump_entries
),
3256 &mod
->num_jump_entries
);
3258 #ifdef CONFIG_EVENT_TRACING
3259 mod
->trace_events
= section_objs(info
, "_ftrace_events",
3260 sizeof(*mod
->trace_events
),
3261 &mod
->num_trace_events
);
3262 mod
->trace_evals
= section_objs(info
, "_ftrace_eval_map",
3263 sizeof(*mod
->trace_evals
),
3264 &mod
->num_trace_evals
);
3266 #ifdef CONFIG_TRACING
3267 mod
->trace_bprintk_fmt_start
= section_objs(info
, "__trace_printk_fmt",
3268 sizeof(*mod
->trace_bprintk_fmt_start
),
3269 &mod
->num_trace_bprintk_fmt
);
3271 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
3272 /* sechdrs[0].sh_size is always zero */
3273 mod
->ftrace_callsites
= section_objs(info
, FTRACE_CALLSITE_SECTION
,
3274 sizeof(*mod
->ftrace_callsites
),
3275 &mod
->num_ftrace_callsites
);
3277 #ifdef CONFIG_FUNCTION_ERROR_INJECTION
3278 mod
->ei_funcs
= section_objs(info
, "_error_injection_whitelist",
3279 sizeof(*mod
->ei_funcs
),
3280 &mod
->num_ei_funcs
);
3282 #ifdef CONFIG_KPROBES
3283 mod
->kprobes_text_start
= section_objs(info
, ".kprobes.text", 1,
3284 &mod
->kprobes_text_size
);
3285 mod
->kprobe_blacklist
= section_objs(info
, "_kprobe_blacklist",
3286 sizeof(unsigned long),
3287 &mod
->num_kprobe_blacklist
);
3289 #ifdef CONFIG_HAVE_STATIC_CALL_INLINE
3290 mod
->static_call_sites
= section_objs(info
, ".static_call_sites",
3291 sizeof(*mod
->static_call_sites
),
3292 &mod
->num_static_call_sites
);
3294 mod
->extable
= section_objs(info
, "__ex_table",
3295 sizeof(*mod
->extable
), &mod
->num_exentries
);
3297 if (section_addr(info
, "__obsparm"))
3298 pr_warn("%s: Ignoring obsolete parameters\n", mod
->name
);
3300 info
->debug
= section_objs(info
, "__dyndbg",
3301 sizeof(*info
->debug
), &info
->num_debug
);
3306 static int move_module(struct module
*mod
, struct load_info
*info
)
3311 /* Do the allocs. */
3312 ptr
= module_alloc(mod
->core_layout
.size
);
3314 * The pointer to this block is stored in the module structure
3315 * which is inside the block. Just mark it as not being a
3318 kmemleak_not_leak(ptr
);
3322 memset(ptr
, 0, mod
->core_layout
.size
);
3323 mod
->core_layout
.base
= ptr
;
3325 if (mod
->init_layout
.size
) {
3326 ptr
= module_alloc(mod
->init_layout
.size
);
3328 * The pointer to this block is stored in the module structure
3329 * which is inside the block. This block doesn't need to be
3330 * scanned as it contains data and code that will be freed
3331 * after the module is initialized.
3333 kmemleak_ignore(ptr
);
3335 module_memfree(mod
->core_layout
.base
);
3338 memset(ptr
, 0, mod
->init_layout
.size
);
3339 mod
->init_layout
.base
= ptr
;
3341 mod
->init_layout
.base
= NULL
;
3343 /* Transfer each section which specifies SHF_ALLOC */
3344 pr_debug("final section addresses:\n");
3345 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++) {
3347 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
3349 if (!(shdr
->sh_flags
& SHF_ALLOC
))
3352 if (shdr
->sh_entsize
& INIT_OFFSET_MASK
)
3353 dest
= mod
->init_layout
.base
3354 + (shdr
->sh_entsize
& ~INIT_OFFSET_MASK
);
3356 dest
= mod
->core_layout
.base
+ shdr
->sh_entsize
;
3358 if (shdr
->sh_type
!= SHT_NOBITS
)
3359 memcpy(dest
, (void *)shdr
->sh_addr
, shdr
->sh_size
);
3360 /* Update sh_addr to point to copy in image. */
3361 shdr
->sh_addr
= (unsigned long)dest
;
3362 pr_debug("\t0x%lx %s\n",
3363 (long)shdr
->sh_addr
, info
->secstrings
+ shdr
->sh_name
);
3369 static int check_module_license_and_versions(struct module
*mod
)
3371 int prev_taint
= test_taint(TAINT_PROPRIETARY_MODULE
);
3374 * ndiswrapper is under GPL by itself, but loads proprietary modules.
3375 * Don't use add_taint_module(), as it would prevent ndiswrapper from
3376 * using GPL-only symbols it needs.
3378 if (strcmp(mod
->name
, "ndiswrapper") == 0)
3379 add_taint(TAINT_PROPRIETARY_MODULE
, LOCKDEP_NOW_UNRELIABLE
);
3381 /* driverloader was caught wrongly pretending to be under GPL */
3382 if (strcmp(mod
->name
, "driverloader") == 0)
3383 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
3384 LOCKDEP_NOW_UNRELIABLE
);
3386 /* lve claims to be GPL but upstream won't provide source */
3387 if (strcmp(mod
->name
, "lve") == 0)
3388 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
3389 LOCKDEP_NOW_UNRELIABLE
);
3391 if (!prev_taint
&& test_taint(TAINT_PROPRIETARY_MODULE
))
3392 pr_warn("%s: module license taints kernel.\n", mod
->name
);
3394 #ifdef CONFIG_MODVERSIONS
3395 if ((mod
->num_syms
&& !mod
->crcs
)
3396 || (mod
->num_gpl_syms
&& !mod
->gpl_crcs
)
3397 || (mod
->num_gpl_future_syms
&& !mod
->gpl_future_crcs
)
3398 #ifdef CONFIG_UNUSED_SYMBOLS
3399 || (mod
->num_unused_syms
&& !mod
->unused_crcs
)
3400 || (mod
->num_unused_gpl_syms
&& !mod
->unused_gpl_crcs
)
3403 return try_to_force_load(mod
,
3404 "no versions for exported symbols");
3410 static void flush_module_icache(const struct module
*mod
)
3413 * Flush the instruction cache, since we've played with text.
3414 * Do it before processing of module parameters, so the module
3415 * can provide parameter accessor functions of its own.
3417 if (mod
->init_layout
.base
)
3418 flush_icache_range((unsigned long)mod
->init_layout
.base
,
3419 (unsigned long)mod
->init_layout
.base
3420 + mod
->init_layout
.size
);
3421 flush_icache_range((unsigned long)mod
->core_layout
.base
,
3422 (unsigned long)mod
->core_layout
.base
+ mod
->core_layout
.size
);
3425 int __weak
module_frob_arch_sections(Elf_Ehdr
*hdr
,
3433 /* module_blacklist is a comma-separated list of module names */
3434 static char *module_blacklist
;
3435 static bool blacklisted(const char *module_name
)
3440 if (!module_blacklist
)
3443 for (p
= module_blacklist
; *p
; p
+= len
) {
3444 len
= strcspn(p
, ",");
3445 if (strlen(module_name
) == len
&& !memcmp(module_name
, p
, len
))
3452 core_param(module_blacklist
, module_blacklist
, charp
, 0400);
3454 static struct module
*layout_and_allocate(struct load_info
*info
, int flags
)
3460 err
= check_modinfo(info
->mod
, info
, flags
);
3462 return ERR_PTR(err
);
3464 /* Allow arches to frob section contents and sizes. */
3465 err
= module_frob_arch_sections(info
->hdr
, info
->sechdrs
,
3466 info
->secstrings
, info
->mod
);
3468 return ERR_PTR(err
);
3470 err
= module_enforce_rwx_sections(info
->hdr
, info
->sechdrs
,
3471 info
->secstrings
, info
->mod
);
3473 return ERR_PTR(err
);
3475 /* We will do a special allocation for per-cpu sections later. */
3476 info
->sechdrs
[info
->index
.pcpu
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
3479 * Mark ro_after_init section with SHF_RO_AFTER_INIT so that
3480 * layout_sections() can put it in the right place.
3481 * Note: ro_after_init sections also have SHF_{WRITE,ALLOC} set.
3483 ndx
= find_sec(info
, ".data..ro_after_init");
3485 info
->sechdrs
[ndx
].sh_flags
|= SHF_RO_AFTER_INIT
;
3487 * Mark the __jump_table section as ro_after_init as well: these data
3488 * structures are never modified, with the exception of entries that
3489 * refer to code in the __init section, which are annotated as such
3490 * at module load time.
3492 ndx
= find_sec(info
, "__jump_table");
3494 info
->sechdrs
[ndx
].sh_flags
|= SHF_RO_AFTER_INIT
;
3496 /* Determine total sizes, and put offsets in sh_entsize. For now
3497 this is done generically; there doesn't appear to be any
3498 special cases for the architectures. */
3499 layout_sections(info
->mod
, info
);
3500 layout_symtab(info
->mod
, info
);
3502 /* Allocate and move to the final place */
3503 err
= move_module(info
->mod
, info
);
3505 return ERR_PTR(err
);
3507 /* Module has been copied to its final place now: return it. */
3508 mod
= (void *)info
->sechdrs
[info
->index
.mod
].sh_addr
;
3509 kmemleak_load_module(mod
, info
);
3513 /* mod is no longer valid after this! */
3514 static void module_deallocate(struct module
*mod
, struct load_info
*info
)
3516 percpu_modfree(mod
);
3517 module_arch_freeing_init(mod
);
3518 module_memfree(mod
->init_layout
.base
);
3519 module_memfree(mod
->core_layout
.base
);
3522 int __weak
module_finalize(const Elf_Ehdr
*hdr
,
3523 const Elf_Shdr
*sechdrs
,
3529 static int post_relocation(struct module
*mod
, const struct load_info
*info
)
3531 /* Sort exception table now relocations are done. */
3532 sort_extable(mod
->extable
, mod
->extable
+ mod
->num_exentries
);
3534 /* Copy relocated percpu area over. */
3535 percpu_modcopy(mod
, (void *)info
->sechdrs
[info
->index
.pcpu
].sh_addr
,
3536 info
->sechdrs
[info
->index
.pcpu
].sh_size
);
3538 /* Setup kallsyms-specific fields. */
3539 add_kallsyms(mod
, info
);
3541 /* Arch-specific module finalizing. */
3542 return module_finalize(info
->hdr
, info
->sechdrs
, mod
);
3545 /* Is this module of this name done loading? No locks held. */
3546 static bool finished_loading(const char *name
)
3552 * The module_mutex should not be a heavily contended lock;
3553 * if we get the occasional sleep here, we'll go an extra iteration
3554 * in the wait_event_interruptible(), which is harmless.
3556 sched_annotate_sleep();
3557 mutex_lock(&module_mutex
);
3558 mod
= find_module_all(name
, strlen(name
), true);
3559 ret
= !mod
|| mod
->state
== MODULE_STATE_LIVE
;
3560 mutex_unlock(&module_mutex
);
3565 /* Call module constructors. */
3566 static void do_mod_ctors(struct module
*mod
)
3568 #ifdef CONFIG_CONSTRUCTORS
3571 for (i
= 0; i
< mod
->num_ctors
; i
++)
3576 /* For freeing module_init on success, in case kallsyms traversing */
3577 struct mod_initfree
{
3578 struct llist_node node
;
3582 static void do_free_init(struct work_struct
*w
)
3584 struct llist_node
*pos
, *n
, *list
;
3585 struct mod_initfree
*initfree
;
3587 list
= llist_del_all(&init_free_list
);
3591 llist_for_each_safe(pos
, n
, list
) {
3592 initfree
= container_of(pos
, struct mod_initfree
, node
);
3593 module_memfree(initfree
->module_init
);
3599 * This is where the real work happens.
3601 * Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb
3602 * helper command 'lx-symbols'.
3604 static noinline
int do_init_module(struct module
*mod
)
3607 struct mod_initfree
*freeinit
;
3609 freeinit
= kmalloc(sizeof(*freeinit
), GFP_KERNEL
);
3614 freeinit
->module_init
= mod
->init_layout
.base
;
3617 * We want to find out whether @mod uses async during init. Clear
3618 * PF_USED_ASYNC. async_schedule*() will set it.
3620 current
->flags
&= ~PF_USED_ASYNC
;
3623 /* Start the module */
3624 if (mod
->init
!= NULL
)
3625 ret
= do_one_initcall(mod
->init
);
3627 goto fail_free_freeinit
;
3630 pr_warn("%s: '%s'->init suspiciously returned %d, it should "
3631 "follow 0/-E convention\n"
3632 "%s: loading module anyway...\n",
3633 __func__
, mod
->name
, ret
, __func__
);
3637 /* Now it's a first class citizen! */
3638 mod
->state
= MODULE_STATE_LIVE
;
3639 blocking_notifier_call_chain(&module_notify_list
,
3640 MODULE_STATE_LIVE
, mod
);
3643 * We need to finish all async code before the module init sequence
3644 * is done. This has potential to deadlock. For example, a newly
3645 * detected block device can trigger request_module() of the
3646 * default iosched from async probing task. Once userland helper
3647 * reaches here, async_synchronize_full() will wait on the async
3648 * task waiting on request_module() and deadlock.
3650 * This deadlock is avoided by perfomring async_synchronize_full()
3651 * iff module init queued any async jobs. This isn't a full
3652 * solution as it will deadlock the same if module loading from
3653 * async jobs nests more than once; however, due to the various
3654 * constraints, this hack seems to be the best option for now.
3655 * Please refer to the following thread for details.
3657 * http://thread.gmane.org/gmane.linux.kernel/1420814
3659 if (!mod
->async_probe_requested
&& (current
->flags
& PF_USED_ASYNC
))
3660 async_synchronize_full();
3662 ftrace_free_mem(mod
, mod
->init_layout
.base
, mod
->init_layout
.base
+
3663 mod
->init_layout
.size
);
3664 mutex_lock(&module_mutex
);
3665 /* Drop initial reference. */
3667 trim_init_extable(mod
);
3668 #ifdef CONFIG_KALLSYMS
3669 /* Switch to core kallsyms now init is done: kallsyms may be walking! */
3670 rcu_assign_pointer(mod
->kallsyms
, &mod
->core_kallsyms
);
3672 module_enable_ro(mod
, true);
3673 mod_tree_remove_init(mod
);
3674 module_arch_freeing_init(mod
);
3675 mod
->init_layout
.base
= NULL
;
3676 mod
->init_layout
.size
= 0;
3677 mod
->init_layout
.ro_size
= 0;
3678 mod
->init_layout
.ro_after_init_size
= 0;
3679 mod
->init_layout
.text_size
= 0;
3681 * We want to free module_init, but be aware that kallsyms may be
3682 * walking this with preempt disabled. In all the failure paths, we
3683 * call synchronize_rcu(), but we don't want to slow down the success
3684 * path. module_memfree() cannot be called in an interrupt, so do the
3685 * work and call synchronize_rcu() in a work queue.
3687 * Note that module_alloc() on most architectures creates W+X page
3688 * mappings which won't be cleaned up until do_free_init() runs. Any
3689 * code such as mark_rodata_ro() which depends on those mappings to
3690 * be cleaned up needs to sync with the queued work - ie
3693 if (llist_add(&freeinit
->node
, &init_free_list
))
3694 schedule_work(&init_free_wq
);
3696 mutex_unlock(&module_mutex
);
3697 wake_up_all(&module_wq
);
3704 /* Try to protect us from buggy refcounters. */
3705 mod
->state
= MODULE_STATE_GOING
;
3708 blocking_notifier_call_chain(&module_notify_list
,
3709 MODULE_STATE_GOING
, mod
);
3710 klp_module_going(mod
);
3711 ftrace_release_mod(mod
);
3713 wake_up_all(&module_wq
);
3717 static int may_init_module(void)
3719 if (!capable(CAP_SYS_MODULE
) || modules_disabled
)
3726 * We try to place it in the list now to make sure it's unique before
3727 * we dedicate too many resources. In particular, temporary percpu
3728 * memory exhaustion.
3730 static int add_unformed_module(struct module
*mod
)
3735 mod
->state
= MODULE_STATE_UNFORMED
;
3738 mutex_lock(&module_mutex
);
3739 old
= find_module_all(mod
->name
, strlen(mod
->name
), true);
3741 if (old
->state
!= MODULE_STATE_LIVE
) {
3742 /* Wait in case it fails to load. */
3743 mutex_unlock(&module_mutex
);
3744 err
= wait_event_interruptible(module_wq
,
3745 finished_loading(mod
->name
));
3753 mod_update_bounds(mod
);
3754 list_add_rcu(&mod
->list
, &modules
);
3755 mod_tree_insert(mod
);
3759 mutex_unlock(&module_mutex
);
3764 static int complete_formation(struct module
*mod
, struct load_info
*info
)
3768 mutex_lock(&module_mutex
);
3770 /* Find duplicate symbols (must be called under lock). */
3771 err
= verify_exported_symbols(mod
);
3775 /* This relies on module_mutex for list integrity. */
3776 module_bug_finalize(info
->hdr
, info
->sechdrs
, mod
);
3778 module_enable_ro(mod
, false);
3779 module_enable_nx(mod
);
3780 module_enable_x(mod
);
3782 /* Mark state as coming so strong_try_module_get() ignores us,
3783 * but kallsyms etc. can see us. */
3784 mod
->state
= MODULE_STATE_COMING
;
3785 mutex_unlock(&module_mutex
);
3790 mutex_unlock(&module_mutex
);
3794 static int prepare_coming_module(struct module
*mod
)
3798 ftrace_module_enable(mod
);
3799 err
= klp_module_coming(mod
);
3803 err
= blocking_notifier_call_chain_robust(&module_notify_list
,
3804 MODULE_STATE_COMING
, MODULE_STATE_GOING
, mod
);
3805 err
= notifier_to_errno(err
);
3807 klp_module_going(mod
);
3812 static int unknown_module_param_cb(char *param
, char *val
, const char *modname
,
3815 struct module
*mod
= arg
;
3818 if (strcmp(param
, "async_probe") == 0) {
3819 mod
->async_probe_requested
= true;
3823 /* Check for magic 'dyndbg' arg */
3824 ret
= ddebug_dyndbg_module_param_cb(param
, val
, modname
);
3826 pr_warn("%s: unknown parameter '%s' ignored\n", modname
, param
);
3830 /* Allocate and load the module: note that size of section 0 is always
3831 zero, and we rely on this for optional sections. */
3832 static int load_module(struct load_info
*info
, const char __user
*uargs
,
3839 err
= elf_header_check(info
);
3841 pr_err("Module has invalid ELF header\n");
3845 err
= setup_load_info(info
, flags
);
3849 if (blacklisted(info
->name
)) {
3851 pr_err("Module %s is blacklisted\n", info
->name
);
3855 err
= module_sig_check(info
, flags
);
3859 err
= rewrite_section_headers(info
, flags
);
3863 /* Check module struct version now, before we try to use module. */
3864 if (!check_modstruct_version(info
, info
->mod
)) {
3869 /* Figure out module layout, and allocate all the memory. */
3870 mod
= layout_and_allocate(info
, flags
);
3876 audit_log_kern_module(mod
->name
);
3878 /* Reserve our place in the list. */
3879 err
= add_unformed_module(mod
);
3883 #ifdef CONFIG_MODULE_SIG
3884 mod
->sig_ok
= info
->sig_ok
;
3886 pr_notice_once("%s: module verification failed: signature "
3887 "and/or required key missing - tainting "
3888 "kernel\n", mod
->name
);
3889 add_taint_module(mod
, TAINT_UNSIGNED_MODULE
, LOCKDEP_STILL_OK
);
3893 /* To avoid stressing percpu allocator, do this once we're unique. */
3894 err
= percpu_modalloc(mod
, info
);
3898 /* Now module is in final location, initialize linked lists, etc. */
3899 err
= module_unload_init(mod
);
3903 init_param_lock(mod
);
3905 /* Now we've got everything in the final locations, we can
3906 * find optional sections. */
3907 err
= find_module_sections(mod
, info
);
3911 err
= check_module_license_and_versions(mod
);
3915 /* Set up MODINFO_ATTR fields */
3916 setup_modinfo(mod
, info
);
3918 /* Fix up syms, so that st_value is a pointer to location. */
3919 err
= simplify_symbols(mod
, info
);
3923 err
= apply_relocations(mod
, info
);
3927 err
= post_relocation(mod
, info
);
3931 flush_module_icache(mod
);
3933 /* Now copy in args */
3934 mod
->args
= strndup_user(uargs
, ~0UL >> 1);
3935 if (IS_ERR(mod
->args
)) {
3936 err
= PTR_ERR(mod
->args
);
3937 goto free_arch_cleanup
;
3940 dynamic_debug_setup(mod
, info
->debug
, info
->num_debug
);
3942 /* Ftrace init must be called in the MODULE_STATE_UNFORMED state */
3943 ftrace_module_init(mod
);
3945 /* Finally it's fully formed, ready to start executing. */
3946 err
= complete_formation(mod
, info
);
3948 goto ddebug_cleanup
;
3950 err
= prepare_coming_module(mod
);
3954 /* Module is ready to execute: parsing args may do that. */
3955 after_dashes
= parse_args(mod
->name
, mod
->args
, mod
->kp
, mod
->num_kp
,
3957 unknown_module_param_cb
);
3958 if (IS_ERR(after_dashes
)) {
3959 err
= PTR_ERR(after_dashes
);
3960 goto coming_cleanup
;
3961 } else if (after_dashes
) {
3962 pr_warn("%s: parameters '%s' after `--' ignored\n",
3963 mod
->name
, after_dashes
);
3966 /* Link in to sysfs. */
3967 err
= mod_sysfs_setup(mod
, info
, mod
->kp
, mod
->num_kp
);
3969 goto coming_cleanup
;
3971 if (is_livepatch_module(mod
)) {
3972 err
= copy_module_elf(mod
, info
);
3977 /* Get rid of temporary copy. */
3981 trace_module_load(mod
);
3983 return do_init_module(mod
);
3986 mod_sysfs_teardown(mod
);
3988 mod
->state
= MODULE_STATE_GOING
;
3989 destroy_params(mod
->kp
, mod
->num_kp
);
3990 blocking_notifier_call_chain(&module_notify_list
,
3991 MODULE_STATE_GOING
, mod
);
3992 klp_module_going(mod
);
3994 /* module_bug_cleanup needs module_mutex protection */
3995 mutex_lock(&module_mutex
);
3996 module_bug_cleanup(mod
);
3997 mutex_unlock(&module_mutex
);
4000 ftrace_release_mod(mod
);
4001 dynamic_debug_remove(mod
, info
->debug
);
4005 module_arch_cleanup(mod
);
4009 module_unload_free(mod
);
4011 mutex_lock(&module_mutex
);
4012 /* Unlink carefully: kallsyms could be walking list. */
4013 list_del_rcu(&mod
->list
);
4014 mod_tree_remove(mod
);
4015 wake_up_all(&module_wq
);
4016 /* Wait for RCU-sched synchronizing before releasing mod->list. */
4018 mutex_unlock(&module_mutex
);
4020 /* Free lock-classes; relies on the preceding sync_rcu() */
4021 lockdep_free_key_range(mod
->core_layout
.base
, mod
->core_layout
.size
);
4023 module_deallocate(mod
, info
);
4029 SYSCALL_DEFINE3(init_module
, void __user
*, umod
,
4030 unsigned long, len
, const char __user
*, uargs
)
4033 struct load_info info
= { };
4035 err
= may_init_module();
4039 pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
4042 err
= copy_module_from_user(umod
, len
, &info
);
4046 return load_module(&info
, uargs
, 0);
4049 SYSCALL_DEFINE3(finit_module
, int, fd
, const char __user
*, uargs
, int, flags
)
4051 struct load_info info
= { };
4055 err
= may_init_module();
4059 pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd
, uargs
, flags
);
4061 if (flags
& ~(MODULE_INIT_IGNORE_MODVERSIONS
4062 |MODULE_INIT_IGNORE_VERMAGIC
))
4065 err
= kernel_read_file_from_fd(fd
, 0, &hdr
, INT_MAX
, NULL
,
4072 return load_module(&info
, uargs
, flags
);
4075 static inline int within(unsigned long addr
, void *start
, unsigned long size
)
4077 return ((void *)addr
>= start
&& (void *)addr
< start
+ size
);
4080 #ifdef CONFIG_KALLSYMS
4082 * This ignores the intensely annoying "mapping symbols" found
4083 * in ARM ELF files: $a, $t and $d.
4085 static inline int is_arm_mapping_symbol(const char *str
)
4087 if (str
[0] == '.' && str
[1] == 'L')
4089 return str
[0] == '$' && strchr("axtd", str
[1])
4090 && (str
[2] == '\0' || str
[2] == '.');
4093 static const char *kallsyms_symbol_name(struct mod_kallsyms
*kallsyms
, unsigned int symnum
)
4095 return kallsyms
->strtab
+ kallsyms
->symtab
[symnum
].st_name
;
4099 * Given a module and address, find the corresponding symbol and return its name
4100 * while providing its size and offset if needed.
4102 static const char *find_kallsyms_symbol(struct module
*mod
,
4104 unsigned long *size
,
4105 unsigned long *offset
)
4107 unsigned int i
, best
= 0;
4108 unsigned long nextval
, bestval
;
4109 struct mod_kallsyms
*kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
4111 /* At worse, next value is at end of module */
4112 if (within_module_init(addr
, mod
))
4113 nextval
= (unsigned long)mod
->init_layout
.base
+mod
->init_layout
.text_size
;
4115 nextval
= (unsigned long)mod
->core_layout
.base
+mod
->core_layout
.text_size
;
4117 bestval
= kallsyms_symbol_value(&kallsyms
->symtab
[best
]);
4119 /* Scan for closest preceding symbol, and next symbol. (ELF
4120 starts real symbols at 1). */
4121 for (i
= 1; i
< kallsyms
->num_symtab
; i
++) {
4122 const Elf_Sym
*sym
= &kallsyms
->symtab
[i
];
4123 unsigned long thisval
= kallsyms_symbol_value(sym
);
4125 if (sym
->st_shndx
== SHN_UNDEF
)
4128 /* We ignore unnamed symbols: they're uninformative
4129 * and inserted at a whim. */
4130 if (*kallsyms_symbol_name(kallsyms
, i
) == '\0'
4131 || is_arm_mapping_symbol(kallsyms_symbol_name(kallsyms
, i
)))
4134 if (thisval
<= addr
&& thisval
> bestval
) {
4138 if (thisval
> addr
&& thisval
< nextval
)
4146 *size
= nextval
- bestval
;
4148 *offset
= addr
- bestval
;
4150 return kallsyms_symbol_name(kallsyms
, best
);
4153 void * __weak
dereference_module_function_descriptor(struct module
*mod
,
4159 /* For kallsyms to ask for address resolution. NULL means not found. Careful
4160 * not to lock to avoid deadlock on oopses, simply disable preemption. */
4161 const char *module_address_lookup(unsigned long addr
,
4162 unsigned long *size
,
4163 unsigned long *offset
,
4167 const char *ret
= NULL
;
4171 mod
= __module_address(addr
);
4174 *modname
= mod
->name
;
4176 ret
= find_kallsyms_symbol(mod
, addr
, size
, offset
);
4178 /* Make a copy in here where it's safe */
4180 strncpy(namebuf
, ret
, KSYM_NAME_LEN
- 1);
4188 int lookup_module_symbol_name(unsigned long addr
, char *symname
)
4193 list_for_each_entry_rcu(mod
, &modules
, list
) {
4194 if (mod
->state
== MODULE_STATE_UNFORMED
)
4196 if (within_module(addr
, mod
)) {
4199 sym
= find_kallsyms_symbol(mod
, addr
, NULL
, NULL
);
4203 strlcpy(symname
, sym
, KSYM_NAME_LEN
);
4213 int lookup_module_symbol_attrs(unsigned long addr
, unsigned long *size
,
4214 unsigned long *offset
, char *modname
, char *name
)
4219 list_for_each_entry_rcu(mod
, &modules
, list
) {
4220 if (mod
->state
== MODULE_STATE_UNFORMED
)
4222 if (within_module(addr
, mod
)) {
4225 sym
= find_kallsyms_symbol(mod
, addr
, size
, offset
);
4229 strlcpy(modname
, mod
->name
, MODULE_NAME_LEN
);
4231 strlcpy(name
, sym
, KSYM_NAME_LEN
);
4241 int module_get_kallsym(unsigned int symnum
, unsigned long *value
, char *type
,
4242 char *name
, char *module_name
, int *exported
)
4247 list_for_each_entry_rcu(mod
, &modules
, list
) {
4248 struct mod_kallsyms
*kallsyms
;
4250 if (mod
->state
== MODULE_STATE_UNFORMED
)
4252 kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
4253 if (symnum
< kallsyms
->num_symtab
) {
4254 const Elf_Sym
*sym
= &kallsyms
->symtab
[symnum
];
4256 *value
= kallsyms_symbol_value(sym
);
4257 *type
= kallsyms
->typetab
[symnum
];
4258 strlcpy(name
, kallsyms_symbol_name(kallsyms
, symnum
), KSYM_NAME_LEN
);
4259 strlcpy(module_name
, mod
->name
, MODULE_NAME_LEN
);
4260 *exported
= is_exported(name
, *value
, mod
);
4264 symnum
-= kallsyms
->num_symtab
;
4270 /* Given a module and name of symbol, find and return the symbol's value */
4271 static unsigned long find_kallsyms_symbol_value(struct module
*mod
, const char *name
)
4274 struct mod_kallsyms
*kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
4276 for (i
= 0; i
< kallsyms
->num_symtab
; i
++) {
4277 const Elf_Sym
*sym
= &kallsyms
->symtab
[i
];
4279 if (strcmp(name
, kallsyms_symbol_name(kallsyms
, i
)) == 0 &&
4280 sym
->st_shndx
!= SHN_UNDEF
)
4281 return kallsyms_symbol_value(sym
);
4286 /* Look for this name: can be of form module:name. */
4287 unsigned long module_kallsyms_lookup_name(const char *name
)
4291 unsigned long ret
= 0;
4293 /* Don't lock: we're in enough trouble already. */
4295 if ((colon
= strnchr(name
, MODULE_NAME_LEN
, ':')) != NULL
) {
4296 if ((mod
= find_module_all(name
, colon
- name
, false)) != NULL
)
4297 ret
= find_kallsyms_symbol_value(mod
, colon
+1);
4299 list_for_each_entry_rcu(mod
, &modules
, list
) {
4300 if (mod
->state
== MODULE_STATE_UNFORMED
)
4302 if ((ret
= find_kallsyms_symbol_value(mod
, name
)) != 0)
4310 int module_kallsyms_on_each_symbol(int (*fn
)(void *, const char *,
4311 struct module
*, unsigned long),
4318 module_assert_mutex();
4320 list_for_each_entry(mod
, &modules
, list
) {
4321 /* We hold module_mutex: no need for rcu_dereference_sched */
4322 struct mod_kallsyms
*kallsyms
= mod
->kallsyms
;
4324 if (mod
->state
== MODULE_STATE_UNFORMED
)
4326 for (i
= 0; i
< kallsyms
->num_symtab
; i
++) {
4327 const Elf_Sym
*sym
= &kallsyms
->symtab
[i
];
4329 if (sym
->st_shndx
== SHN_UNDEF
)
4332 ret
= fn(data
, kallsyms_symbol_name(kallsyms
, i
),
4333 mod
, kallsyms_symbol_value(sym
));
4340 #endif /* CONFIG_KALLSYMS */
4342 /* Maximum number of characters written by module_flags() */
4343 #define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4)
4345 /* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */
4346 static char *module_flags(struct module
*mod
, char *buf
)
4350 BUG_ON(mod
->state
== MODULE_STATE_UNFORMED
);
4352 mod
->state
== MODULE_STATE_GOING
||
4353 mod
->state
== MODULE_STATE_COMING
) {
4355 bx
+= module_flags_taint(mod
, buf
+ bx
);
4356 /* Show a - for module-is-being-unloaded */
4357 if (mod
->state
== MODULE_STATE_GOING
)
4359 /* Show a + for module-is-being-loaded */
4360 if (mod
->state
== MODULE_STATE_COMING
)
4369 #ifdef CONFIG_PROC_FS
4370 /* Called by the /proc file system to return a list of modules. */
4371 static void *m_start(struct seq_file
*m
, loff_t
*pos
)
4373 mutex_lock(&module_mutex
);
4374 return seq_list_start(&modules
, *pos
);
4377 static void *m_next(struct seq_file
*m
, void *p
, loff_t
*pos
)
4379 return seq_list_next(p
, &modules
, pos
);
4382 static void m_stop(struct seq_file
*m
, void *p
)
4384 mutex_unlock(&module_mutex
);
4387 static int m_show(struct seq_file
*m
, void *p
)
4389 struct module
*mod
= list_entry(p
, struct module
, list
);
4390 char buf
[MODULE_FLAGS_BUF_SIZE
];
4393 /* We always ignore unformed modules. */
4394 if (mod
->state
== MODULE_STATE_UNFORMED
)
4397 seq_printf(m
, "%s %u",
4398 mod
->name
, mod
->init_layout
.size
+ mod
->core_layout
.size
);
4399 print_unload_info(m
, mod
);
4401 /* Informative for users. */
4402 seq_printf(m
, " %s",
4403 mod
->state
== MODULE_STATE_GOING
? "Unloading" :
4404 mod
->state
== MODULE_STATE_COMING
? "Loading" :
4406 /* Used by oprofile and other similar tools. */
4407 value
= m
->private ? NULL
: mod
->core_layout
.base
;
4408 seq_printf(m
, " 0x%px", value
);
4412 seq_printf(m
, " %s", module_flags(mod
, buf
));
4418 /* Format: modulename size refcount deps address
4420 Where refcount is a number or -, and deps is a comma-separated list
4423 static const struct seq_operations modules_op
= {
4431 * This also sets the "private" pointer to non-NULL if the
4432 * kernel pointers should be hidden (so you can just test
4433 * "m->private" to see if you should keep the values private).
4435 * We use the same logic as for /proc/kallsyms.
4437 static int modules_open(struct inode
*inode
, struct file
*file
)
4439 int err
= seq_open(file
, &modules_op
);
4442 struct seq_file
*m
= file
->private_data
;
4443 m
->private = kallsyms_show_value(file
->f_cred
) ? NULL
: (void *)8ul;
4449 static const struct proc_ops modules_proc_ops
= {
4450 .proc_flags
= PROC_ENTRY_PERMANENT
,
4451 .proc_open
= modules_open
,
4452 .proc_read
= seq_read
,
4453 .proc_lseek
= seq_lseek
,
4454 .proc_release
= seq_release
,
4457 static int __init
proc_modules_init(void)
4459 proc_create("modules", 0, NULL
, &modules_proc_ops
);
4462 module_init(proc_modules_init
);
4465 /* Given an address, look for it in the module exception tables. */
4466 const struct exception_table_entry
*search_module_extables(unsigned long addr
)
4468 const struct exception_table_entry
*e
= NULL
;
4472 mod
= __module_address(addr
);
4476 if (!mod
->num_exentries
)
4479 e
= search_extable(mod
->extable
,
4486 * Now, if we found one, we are running inside it now, hence
4487 * we cannot unload the module, hence no refcnt needed.
4493 * is_module_address - is this address inside a module?
4494 * @addr: the address to check.
4496 * See is_module_text_address() if you simply want to see if the address
4497 * is code (not data).
4499 bool is_module_address(unsigned long addr
)
4504 ret
= __module_address(addr
) != NULL
;
4511 * __module_address - get the module which contains an address.
4512 * @addr: the address.
4514 * Must be called with preempt disabled or module mutex held so that
4515 * module doesn't get freed during this.
4517 struct module
*__module_address(unsigned long addr
)
4521 if (addr
< module_addr_min
|| addr
> module_addr_max
)
4524 module_assert_mutex_or_preempt();
4526 mod
= mod_find(addr
);
4528 BUG_ON(!within_module(addr
, mod
));
4529 if (mod
->state
== MODULE_STATE_UNFORMED
)
4536 * is_module_text_address - is this address inside module code?
4537 * @addr: the address to check.
4539 * See is_module_address() if you simply want to see if the address is
4540 * anywhere in a module. See kernel_text_address() for testing if an
4541 * address corresponds to kernel or module code.
4543 bool is_module_text_address(unsigned long addr
)
4548 ret
= __module_text_address(addr
) != NULL
;
4555 * __module_text_address - get the module whose code contains an address.
4556 * @addr: the address.
4558 * Must be called with preempt disabled or module mutex held so that
4559 * module doesn't get freed during this.
4561 struct module
*__module_text_address(unsigned long addr
)
4563 struct module
*mod
= __module_address(addr
);
4565 /* Make sure it's within the text section. */
4566 if (!within(addr
, mod
->init_layout
.base
, mod
->init_layout
.text_size
)
4567 && !within(addr
, mod
->core_layout
.base
, mod
->core_layout
.text_size
))
4573 /* Don't grab lock, we're oopsing. */
4574 void print_modules(void)
4577 char buf
[MODULE_FLAGS_BUF_SIZE
];
4579 printk(KERN_DEFAULT
"Modules linked in:");
4580 /* Most callers should already have preempt disabled, but make sure */
4582 list_for_each_entry_rcu(mod
, &modules
, list
) {
4583 if (mod
->state
== MODULE_STATE_UNFORMED
)
4585 pr_cont(" %s%s", mod
->name
, module_flags(mod
, buf
));
4588 if (last_unloaded_module
[0])
4589 pr_cont(" [last unloaded: %s]", last_unloaded_module
);
4593 #ifdef CONFIG_MODVERSIONS
4594 /* Generate the signature for all relevant module structures here.
4595 * If these change, we don't want to try to parse the module. */
4596 void module_layout(struct module
*mod
,
4597 struct modversion_info
*ver
,
4598 struct kernel_param
*kp
,
4599 struct kernel_symbol
*ks
,
4600 struct tracepoint
* const *tp
)
4603 EXPORT_SYMBOL(module_layout
);