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 struct work_struct init_free_wq
;
96 static struct llist_head init_free_list
;
98 #ifdef CONFIG_MODULES_TREE_LOOKUP
101 * Use a latched RB-tree for __module_address(); this allows us to use
102 * RCU-sched lookups of the address from any context.
104 * This is conditional on PERF_EVENTS || TRACING because those can really hit
105 * __module_address() hard by doing a lot of stack unwinding; potentially from
109 static __always_inline
unsigned long __mod_tree_val(struct latch_tree_node
*n
)
111 struct module_layout
*layout
= container_of(n
, struct module_layout
, mtn
.node
);
113 return (unsigned long)layout
->base
;
116 static __always_inline
unsigned long __mod_tree_size(struct latch_tree_node
*n
)
118 struct module_layout
*layout
= container_of(n
, struct module_layout
, mtn
.node
);
120 return (unsigned long)layout
->size
;
123 static __always_inline
bool
124 mod_tree_less(struct latch_tree_node
*a
, struct latch_tree_node
*b
)
126 return __mod_tree_val(a
) < __mod_tree_val(b
);
129 static __always_inline
int
130 mod_tree_comp(void *key
, struct latch_tree_node
*n
)
132 unsigned long val
= (unsigned long)key
;
133 unsigned long start
, end
;
135 start
= __mod_tree_val(n
);
139 end
= start
+ __mod_tree_size(n
);
146 static const struct latch_tree_ops mod_tree_ops
= {
147 .less
= mod_tree_less
,
148 .comp
= mod_tree_comp
,
151 static struct mod_tree_root
{
152 struct latch_tree_root root
;
153 unsigned long addr_min
;
154 unsigned long addr_max
;
155 } mod_tree __cacheline_aligned
= {
159 #define module_addr_min mod_tree.addr_min
160 #define module_addr_max mod_tree.addr_max
162 static noinline
void __mod_tree_insert(struct mod_tree_node
*node
)
164 latch_tree_insert(&node
->node
, &mod_tree
.root
, &mod_tree_ops
);
167 static void __mod_tree_remove(struct mod_tree_node
*node
)
169 latch_tree_erase(&node
->node
, &mod_tree
.root
, &mod_tree_ops
);
173 * These modifications: insert, remove_init and remove; are serialized by the
176 static void mod_tree_insert(struct module
*mod
)
178 mod
->core_layout
.mtn
.mod
= mod
;
179 mod
->init_layout
.mtn
.mod
= mod
;
181 __mod_tree_insert(&mod
->core_layout
.mtn
);
182 if (mod
->init_layout
.size
)
183 __mod_tree_insert(&mod
->init_layout
.mtn
);
186 static void mod_tree_remove_init(struct module
*mod
)
188 if (mod
->init_layout
.size
)
189 __mod_tree_remove(&mod
->init_layout
.mtn
);
192 static void mod_tree_remove(struct module
*mod
)
194 __mod_tree_remove(&mod
->core_layout
.mtn
);
195 mod_tree_remove_init(mod
);
198 static struct module
*mod_find(unsigned long addr
)
200 struct latch_tree_node
*ltn
;
202 ltn
= latch_tree_find((void *)addr
, &mod_tree
.root
, &mod_tree_ops
);
206 return container_of(ltn
, struct mod_tree_node
, node
)->mod
;
209 #else /* MODULES_TREE_LOOKUP */
211 static unsigned long module_addr_min
= -1UL, module_addr_max
= 0;
213 static void mod_tree_insert(struct module
*mod
) { }
214 static void mod_tree_remove_init(struct module
*mod
) { }
215 static void mod_tree_remove(struct module
*mod
) { }
217 static struct module
*mod_find(unsigned long addr
)
221 list_for_each_entry_rcu(mod
, &modules
, list
,
222 lockdep_is_held(&module_mutex
)) {
223 if (within_module(addr
, mod
))
230 #endif /* MODULES_TREE_LOOKUP */
233 * Bounds of module text, for speeding up __module_address.
234 * Protected by module_mutex.
236 static void __mod_update_bounds(void *base
, unsigned int size
)
238 unsigned long min
= (unsigned long)base
;
239 unsigned long max
= min
+ size
;
241 if (min
< module_addr_min
)
242 module_addr_min
= min
;
243 if (max
> module_addr_max
)
244 module_addr_max
= max
;
247 static void mod_update_bounds(struct module
*mod
)
249 __mod_update_bounds(mod
->core_layout
.base
, mod
->core_layout
.size
);
250 if (mod
->init_layout
.size
)
251 __mod_update_bounds(mod
->init_layout
.base
, mod
->init_layout
.size
);
254 #ifdef CONFIG_KGDB_KDB
255 struct list_head
*kdb_modules
= &modules
; /* kdb needs the list of modules */
256 #endif /* CONFIG_KGDB_KDB */
258 static void module_assert_mutex(void)
260 lockdep_assert_held(&module_mutex
);
263 static void module_assert_mutex_or_preempt(void)
265 #ifdef CONFIG_LOCKDEP
266 if (unlikely(!debug_locks
))
269 WARN_ON_ONCE(!rcu_read_lock_sched_held() &&
270 !lockdep_is_held(&module_mutex
));
274 static bool sig_enforce
= IS_ENABLED(CONFIG_MODULE_SIG_FORCE
);
275 module_param(sig_enforce
, bool_enable_only
, 0644);
278 * Export sig_enforce kernel cmdline parameter to allow other subsystems rely
279 * on that instead of directly to CONFIG_MODULE_SIG_FORCE config.
281 bool is_module_sig_enforced(void)
285 EXPORT_SYMBOL(is_module_sig_enforced
);
287 void set_module_sig_enforced(void)
292 /* Block module loading/unloading? */
293 int modules_disabled
= 0;
294 core_param(nomodule
, modules_disabled
, bint
, 0);
296 /* Waiting for a module to finish initializing? */
297 static DECLARE_WAIT_QUEUE_HEAD(module_wq
);
299 static BLOCKING_NOTIFIER_HEAD(module_notify_list
);
301 int register_module_notifier(struct notifier_block
*nb
)
303 return blocking_notifier_chain_register(&module_notify_list
, nb
);
305 EXPORT_SYMBOL(register_module_notifier
);
307 int unregister_module_notifier(struct notifier_block
*nb
)
309 return blocking_notifier_chain_unregister(&module_notify_list
, nb
);
311 EXPORT_SYMBOL(unregister_module_notifier
);
314 * We require a truly strong try_module_get(): 0 means success.
315 * Otherwise an error is returned due to ongoing or failed
316 * initialization etc.
318 static inline int strong_try_module_get(struct module
*mod
)
320 BUG_ON(mod
&& mod
->state
== MODULE_STATE_UNFORMED
);
321 if (mod
&& mod
->state
== MODULE_STATE_COMING
)
323 if (try_module_get(mod
))
329 static inline void add_taint_module(struct module
*mod
, unsigned flag
,
330 enum lockdep_ok lockdep_ok
)
332 add_taint(flag
, lockdep_ok
);
333 set_bit(flag
, &mod
->taints
);
337 * A thread that wants to hold a reference to a module only while it
338 * is running can call this to safely exit. nfsd and lockd use this.
340 void __noreturn
__module_put_and_exit(struct module
*mod
, long code
)
345 EXPORT_SYMBOL(__module_put_and_exit
);
347 /* Find a module section: 0 means not found. */
348 static unsigned int find_sec(const struct load_info
*info
, const char *name
)
352 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
353 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
354 /* Alloc bit cleared means "ignore it." */
355 if ((shdr
->sh_flags
& SHF_ALLOC
)
356 && strcmp(info
->secstrings
+ shdr
->sh_name
, name
) == 0)
362 /* Find a module section, or NULL. */
363 static void *section_addr(const struct load_info
*info
, const char *name
)
365 /* Section 0 has sh_addr 0. */
366 return (void *)info
->sechdrs
[find_sec(info
, name
)].sh_addr
;
369 /* Find a module section, or NULL. Fill in number of "objects" in section. */
370 static void *section_objs(const struct load_info
*info
,
375 unsigned int sec
= find_sec(info
, name
);
377 /* Section 0 has sh_addr 0 and sh_size 0. */
378 *num
= info
->sechdrs
[sec
].sh_size
/ object_size
;
379 return (void *)info
->sechdrs
[sec
].sh_addr
;
382 /* Provided by the linker */
383 extern const struct kernel_symbol __start___ksymtab
[];
384 extern const struct kernel_symbol __stop___ksymtab
[];
385 extern const struct kernel_symbol __start___ksymtab_gpl
[];
386 extern const struct kernel_symbol __stop___ksymtab_gpl
[];
387 extern const struct kernel_symbol __start___ksymtab_gpl_future
[];
388 extern const struct kernel_symbol __stop___ksymtab_gpl_future
[];
389 extern const s32 __start___kcrctab
[];
390 extern const s32 __start___kcrctab_gpl
[];
391 extern const s32 __start___kcrctab_gpl_future
[];
392 #ifdef CONFIG_UNUSED_SYMBOLS
393 extern const struct kernel_symbol __start___ksymtab_unused
[];
394 extern const struct kernel_symbol __stop___ksymtab_unused
[];
395 extern const struct kernel_symbol __start___ksymtab_unused_gpl
[];
396 extern const struct kernel_symbol __stop___ksymtab_unused_gpl
[];
397 extern const s32 __start___kcrctab_unused
[];
398 extern const s32 __start___kcrctab_unused_gpl
[];
401 #ifndef CONFIG_MODVERSIONS
402 #define symversion(base, idx) NULL
404 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
407 static bool each_symbol_in_section(const struct symsearch
*arr
,
408 unsigned int arrsize
,
409 struct module
*owner
,
410 bool (*fn
)(const struct symsearch
*syms
,
411 struct module
*owner
,
417 for (j
= 0; j
< arrsize
; j
++) {
418 if (fn(&arr
[j
], owner
, data
))
425 /* Returns true as soon as fn returns true, otherwise false. */
426 static bool each_symbol_section(bool (*fn
)(const struct symsearch
*arr
,
427 struct module
*owner
,
432 static const struct symsearch arr
[] = {
433 { __start___ksymtab
, __stop___ksymtab
, __start___kcrctab
,
434 NOT_GPL_ONLY
, false },
435 { __start___ksymtab_gpl
, __stop___ksymtab_gpl
,
436 __start___kcrctab_gpl
,
438 { __start___ksymtab_gpl_future
, __stop___ksymtab_gpl_future
,
439 __start___kcrctab_gpl_future
,
440 WILL_BE_GPL_ONLY
, false },
441 #ifdef CONFIG_UNUSED_SYMBOLS
442 { __start___ksymtab_unused
, __stop___ksymtab_unused
,
443 __start___kcrctab_unused
,
444 NOT_GPL_ONLY
, true },
445 { __start___ksymtab_unused_gpl
, __stop___ksymtab_unused_gpl
,
446 __start___kcrctab_unused_gpl
,
451 module_assert_mutex_or_preempt();
453 if (each_symbol_in_section(arr
, ARRAY_SIZE(arr
), NULL
, fn
, data
))
456 list_for_each_entry_rcu(mod
, &modules
, list
,
457 lockdep_is_held(&module_mutex
)) {
458 struct symsearch arr
[] = {
459 { mod
->syms
, mod
->syms
+ mod
->num_syms
, mod
->crcs
,
460 NOT_GPL_ONLY
, false },
461 { mod
->gpl_syms
, mod
->gpl_syms
+ mod
->num_gpl_syms
,
464 { mod
->gpl_future_syms
,
465 mod
->gpl_future_syms
+ mod
->num_gpl_future_syms
,
466 mod
->gpl_future_crcs
,
467 WILL_BE_GPL_ONLY
, false },
468 #ifdef CONFIG_UNUSED_SYMBOLS
470 mod
->unused_syms
+ mod
->num_unused_syms
,
472 NOT_GPL_ONLY
, true },
473 { mod
->unused_gpl_syms
,
474 mod
->unused_gpl_syms
+ mod
->num_unused_gpl_syms
,
475 mod
->unused_gpl_crcs
,
480 if (mod
->state
== MODULE_STATE_UNFORMED
)
483 if (each_symbol_in_section(arr
, ARRAY_SIZE(arr
), mod
, fn
, data
))
489 struct find_symbol_arg
{
496 struct module
*owner
;
498 const struct kernel_symbol
*sym
;
499 enum mod_license license
;
502 static bool check_exported_symbol(const struct symsearch
*syms
,
503 struct module
*owner
,
504 unsigned int symnum
, void *data
)
506 struct find_symbol_arg
*fsa
= data
;
509 if (syms
->license
== GPL_ONLY
)
511 if (syms
->license
== WILL_BE_GPL_ONLY
&& fsa
->warn
) {
512 pr_warn("Symbol %s is being used by a non-GPL module, "
513 "which will not be allowed in the future\n",
518 #ifdef CONFIG_UNUSED_SYMBOLS
519 if (syms
->unused
&& fsa
->warn
) {
520 pr_warn("Symbol %s is marked as UNUSED, however this module is "
521 "using it.\n", fsa
->name
);
522 pr_warn("This symbol will go away in the future.\n");
523 pr_warn("Please evaluate if this is the right api to use and "
524 "if it really is, submit a report to the linux kernel "
525 "mailing list together with submitting your code for "
531 fsa
->crc
= symversion(syms
->crcs
, symnum
);
532 fsa
->sym
= &syms
->start
[symnum
];
533 fsa
->license
= syms
->license
;
537 static unsigned long kernel_symbol_value(const struct kernel_symbol
*sym
)
539 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
540 return (unsigned long)offset_to_ptr(&sym
->value_offset
);
546 static const char *kernel_symbol_name(const struct kernel_symbol
*sym
)
548 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
549 return offset_to_ptr(&sym
->name_offset
);
555 static const char *kernel_symbol_namespace(const struct kernel_symbol
*sym
)
557 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
558 if (!sym
->namespace_offset
)
560 return offset_to_ptr(&sym
->namespace_offset
);
562 return sym
->namespace;
566 static int cmp_name(const void *name
, const void *sym
)
568 return strcmp(name
, kernel_symbol_name(sym
));
571 static bool find_exported_symbol_in_section(const struct symsearch
*syms
,
572 struct module
*owner
,
575 struct find_symbol_arg
*fsa
= data
;
576 struct kernel_symbol
*sym
;
578 sym
= bsearch(fsa
->name
, syms
->start
, syms
->stop
- syms
->start
,
579 sizeof(struct kernel_symbol
), cmp_name
);
581 if (sym
!= NULL
&& check_exported_symbol(syms
, owner
,
582 sym
- syms
->start
, data
))
588 /* Find an exported symbol and return it, along with, (optional) crc and
589 * (optional) module which owns it. Needs preempt disabled or module_mutex. */
590 static const struct kernel_symbol
*find_symbol(const char *name
,
591 struct module
**owner
,
593 enum mod_license
*license
,
597 struct find_symbol_arg fsa
;
603 if (each_symbol_section(find_exported_symbol_in_section
, &fsa
)) {
609 *license
= fsa
.license
;
613 pr_debug("Failed to find symbol %s\n", name
);
618 * Search for module by name: must hold module_mutex (or preempt disabled
619 * for read-only access).
621 static struct module
*find_module_all(const char *name
, size_t len
,
626 module_assert_mutex_or_preempt();
628 list_for_each_entry_rcu(mod
, &modules
, list
,
629 lockdep_is_held(&module_mutex
)) {
630 if (!even_unformed
&& mod
->state
== MODULE_STATE_UNFORMED
)
632 if (strlen(mod
->name
) == len
&& !memcmp(mod
->name
, name
, len
))
638 struct module
*find_module(const char *name
)
640 module_assert_mutex();
641 return find_module_all(name
, strlen(name
), false);
643 EXPORT_SYMBOL_GPL(find_module
);
647 static inline void __percpu
*mod_percpu(struct module
*mod
)
652 static int percpu_modalloc(struct module
*mod
, struct load_info
*info
)
654 Elf_Shdr
*pcpusec
= &info
->sechdrs
[info
->index
.pcpu
];
655 unsigned long align
= pcpusec
->sh_addralign
;
657 if (!pcpusec
->sh_size
)
660 if (align
> PAGE_SIZE
) {
661 pr_warn("%s: per-cpu alignment %li > %li\n",
662 mod
->name
, align
, PAGE_SIZE
);
666 mod
->percpu
= __alloc_reserved_percpu(pcpusec
->sh_size
, align
);
668 pr_warn("%s: Could not allocate %lu bytes percpu data\n",
669 mod
->name
, (unsigned long)pcpusec
->sh_size
);
672 mod
->percpu_size
= pcpusec
->sh_size
;
676 static void percpu_modfree(struct module
*mod
)
678 free_percpu(mod
->percpu
);
681 static unsigned int find_pcpusec(struct load_info
*info
)
683 return find_sec(info
, ".data..percpu");
686 static void percpu_modcopy(struct module
*mod
,
687 const void *from
, unsigned long size
)
691 for_each_possible_cpu(cpu
)
692 memcpy(per_cpu_ptr(mod
->percpu
, cpu
), from
, size
);
695 bool __is_module_percpu_address(unsigned long addr
, unsigned long *can_addr
)
702 list_for_each_entry_rcu(mod
, &modules
, list
) {
703 if (mod
->state
== MODULE_STATE_UNFORMED
)
705 if (!mod
->percpu_size
)
707 for_each_possible_cpu(cpu
) {
708 void *start
= per_cpu_ptr(mod
->percpu
, cpu
);
709 void *va
= (void *)addr
;
711 if (va
>= start
&& va
< start
+ mod
->percpu_size
) {
713 *can_addr
= (unsigned long) (va
- start
);
714 *can_addr
+= (unsigned long)
715 per_cpu_ptr(mod
->percpu
,
729 * is_module_percpu_address - test whether address is from module static percpu
730 * @addr: address to test
732 * Test whether @addr belongs to module static percpu area.
735 * %true if @addr is from module static percpu area
737 bool is_module_percpu_address(unsigned long addr
)
739 return __is_module_percpu_address(addr
, NULL
);
742 #else /* ... !CONFIG_SMP */
744 static inline void __percpu
*mod_percpu(struct module
*mod
)
748 static int percpu_modalloc(struct module
*mod
, struct load_info
*info
)
750 /* UP modules shouldn't have this section: ENOMEM isn't quite right */
751 if (info
->sechdrs
[info
->index
.pcpu
].sh_size
!= 0)
755 static inline void percpu_modfree(struct module
*mod
)
758 static unsigned int find_pcpusec(struct load_info
*info
)
762 static inline void percpu_modcopy(struct module
*mod
,
763 const void *from
, unsigned long size
)
765 /* pcpusec should be 0, and size of that section should be 0. */
768 bool is_module_percpu_address(unsigned long addr
)
773 bool __is_module_percpu_address(unsigned long addr
, unsigned long *can_addr
)
778 #endif /* CONFIG_SMP */
780 #define MODINFO_ATTR(field) \
781 static void setup_modinfo_##field(struct module *mod, const char *s) \
783 mod->field = kstrdup(s, GFP_KERNEL); \
785 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
786 struct module_kobject *mk, char *buffer) \
788 return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \
790 static int modinfo_##field##_exists(struct module *mod) \
792 return mod->field != NULL; \
794 static void free_modinfo_##field(struct module *mod) \
799 static struct module_attribute modinfo_##field = { \
800 .attr = { .name = __stringify(field), .mode = 0444 }, \
801 .show = show_modinfo_##field, \
802 .setup = setup_modinfo_##field, \
803 .test = modinfo_##field##_exists, \
804 .free = free_modinfo_##field, \
807 MODINFO_ATTR(version
);
808 MODINFO_ATTR(srcversion
);
810 static char last_unloaded_module
[MODULE_NAME_LEN
+1];
812 #ifdef CONFIG_MODULE_UNLOAD
814 EXPORT_TRACEPOINT_SYMBOL(module_get
);
816 /* MODULE_REF_BASE is the base reference count by kmodule loader. */
817 #define MODULE_REF_BASE 1
819 /* Init the unload section of the module. */
820 static int module_unload_init(struct module
*mod
)
823 * Initialize reference counter to MODULE_REF_BASE.
824 * refcnt == 0 means module is going.
826 atomic_set(&mod
->refcnt
, MODULE_REF_BASE
);
828 INIT_LIST_HEAD(&mod
->source_list
);
829 INIT_LIST_HEAD(&mod
->target_list
);
831 /* Hold reference count during initialization. */
832 atomic_inc(&mod
->refcnt
);
837 /* Does a already use b? */
838 static int already_uses(struct module
*a
, struct module
*b
)
840 struct module_use
*use
;
842 list_for_each_entry(use
, &b
->source_list
, source_list
) {
843 if (use
->source
== a
) {
844 pr_debug("%s uses %s!\n", a
->name
, b
->name
);
848 pr_debug("%s does not use %s!\n", a
->name
, b
->name
);
854 * - we add 'a' as a "source", 'b' as a "target" of module use
855 * - the module_use is added to the list of 'b' sources (so
856 * 'b' can walk the list to see who sourced them), and of 'a'
857 * targets (so 'a' can see what modules it targets).
859 static int add_module_usage(struct module
*a
, struct module
*b
)
861 struct module_use
*use
;
863 pr_debug("Allocating new usage for %s.\n", a
->name
);
864 use
= kmalloc(sizeof(*use
), GFP_ATOMIC
);
870 list_add(&use
->source_list
, &b
->source_list
);
871 list_add(&use
->target_list
, &a
->target_list
);
875 /* Module a uses b: caller needs module_mutex() */
876 static int ref_module(struct module
*a
, struct module
*b
)
880 if (b
== NULL
|| already_uses(a
, b
))
883 /* If module isn't available, we fail. */
884 err
= strong_try_module_get(b
);
888 err
= add_module_usage(a
, b
);
896 /* Clear the unload stuff of the module. */
897 static void module_unload_free(struct module
*mod
)
899 struct module_use
*use
, *tmp
;
901 mutex_lock(&module_mutex
);
902 list_for_each_entry_safe(use
, tmp
, &mod
->target_list
, target_list
) {
903 struct module
*i
= use
->target
;
904 pr_debug("%s unusing %s\n", mod
->name
, i
->name
);
906 list_del(&use
->source_list
);
907 list_del(&use
->target_list
);
910 mutex_unlock(&module_mutex
);
913 #ifdef CONFIG_MODULE_FORCE_UNLOAD
914 static inline int try_force_unload(unsigned int flags
)
916 int ret
= (flags
& O_TRUNC
);
918 add_taint(TAINT_FORCED_RMMOD
, LOCKDEP_NOW_UNRELIABLE
);
922 static inline int try_force_unload(unsigned int flags
)
926 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
928 /* Try to release refcount of module, 0 means success. */
929 static int try_release_module_ref(struct module
*mod
)
933 /* Try to decrement refcnt which we set at loading */
934 ret
= atomic_sub_return(MODULE_REF_BASE
, &mod
->refcnt
);
937 /* Someone can put this right now, recover with checking */
938 ret
= atomic_add_unless(&mod
->refcnt
, MODULE_REF_BASE
, 0);
943 static int try_stop_module(struct module
*mod
, int flags
, int *forced
)
945 /* If it's not unused, quit unless we're forcing. */
946 if (try_release_module_ref(mod
) != 0) {
947 *forced
= try_force_unload(flags
);
952 /* Mark it as dying. */
953 mod
->state
= MODULE_STATE_GOING
;
959 * module_refcount - return the refcount or -1 if unloading
961 * @mod: the module we're checking
964 * -1 if the module is in the process of unloading
965 * otherwise the number of references in the kernel to the module
967 int module_refcount(struct module
*mod
)
969 return atomic_read(&mod
->refcnt
) - MODULE_REF_BASE
;
971 EXPORT_SYMBOL(module_refcount
);
973 /* This exists whether we can unload or not */
974 static void free_module(struct module
*mod
);
976 SYSCALL_DEFINE2(delete_module
, const char __user
*, name_user
,
980 char name
[MODULE_NAME_LEN
];
983 if (!capable(CAP_SYS_MODULE
) || modules_disabled
)
986 if (strncpy_from_user(name
, name_user
, MODULE_NAME_LEN
-1) < 0)
988 name
[MODULE_NAME_LEN
-1] = '\0';
990 audit_log_kern_module(name
);
992 if (mutex_lock_interruptible(&module_mutex
) != 0)
995 mod
= find_module(name
);
1001 if (!list_empty(&mod
->source_list
)) {
1002 /* Other modules depend on us: get rid of them first. */
1007 /* Doing init or already dying? */
1008 if (mod
->state
!= MODULE_STATE_LIVE
) {
1009 /* FIXME: if (force), slam module count damn the torpedoes */
1010 pr_debug("%s already dying\n", mod
->name
);
1015 /* If it has an init func, it must have an exit func to unload */
1016 if (mod
->init
&& !mod
->exit
) {
1017 forced
= try_force_unload(flags
);
1019 /* This module can't be removed */
1025 /* Stop the machine so refcounts can't move and disable module. */
1026 ret
= try_stop_module(mod
, flags
, &forced
);
1030 mutex_unlock(&module_mutex
);
1031 /* Final destruction now no one is using it. */
1032 if (mod
->exit
!= NULL
)
1034 blocking_notifier_call_chain(&module_notify_list
,
1035 MODULE_STATE_GOING
, mod
);
1036 klp_module_going(mod
);
1037 ftrace_release_mod(mod
);
1039 async_synchronize_full();
1041 /* Store the name of the last unloaded module for diagnostic purposes */
1042 strlcpy(last_unloaded_module
, mod
->name
, sizeof(last_unloaded_module
));
1045 /* someone could wait for the module in add_unformed_module() */
1046 wake_up_all(&module_wq
);
1049 mutex_unlock(&module_mutex
);
1053 static inline void print_unload_info(struct seq_file
*m
, struct module
*mod
)
1055 struct module_use
*use
;
1056 int printed_something
= 0;
1058 seq_printf(m
, " %i ", module_refcount(mod
));
1061 * Always include a trailing , so userspace can differentiate
1062 * between this and the old multi-field proc format.
1064 list_for_each_entry(use
, &mod
->source_list
, source_list
) {
1065 printed_something
= 1;
1066 seq_printf(m
, "%s,", use
->source
->name
);
1069 if (mod
->init
!= NULL
&& mod
->exit
== NULL
) {
1070 printed_something
= 1;
1071 seq_puts(m
, "[permanent],");
1074 if (!printed_something
)
1078 void __symbol_put(const char *symbol
)
1080 struct module
*owner
;
1083 if (!find_symbol(symbol
, &owner
, NULL
, NULL
, true, false))
1088 EXPORT_SYMBOL(__symbol_put
);
1090 /* Note this assumes addr is a function, which it currently always is. */
1091 void symbol_put_addr(void *addr
)
1093 struct module
*modaddr
;
1094 unsigned long a
= (unsigned long)dereference_function_descriptor(addr
);
1096 if (core_kernel_text(a
))
1100 * Even though we hold a reference on the module; we still need to
1101 * disable preemption in order to safely traverse the data structure.
1104 modaddr
= __module_text_address(a
);
1106 module_put(modaddr
);
1109 EXPORT_SYMBOL_GPL(symbol_put_addr
);
1111 static ssize_t
show_refcnt(struct module_attribute
*mattr
,
1112 struct module_kobject
*mk
, char *buffer
)
1114 return sprintf(buffer
, "%i\n", module_refcount(mk
->mod
));
1117 static struct module_attribute modinfo_refcnt
=
1118 __ATTR(refcnt
, 0444, show_refcnt
, NULL
);
1120 void __module_get(struct module
*module
)
1124 atomic_inc(&module
->refcnt
);
1125 trace_module_get(module
, _RET_IP_
);
1129 EXPORT_SYMBOL(__module_get
);
1131 bool try_module_get(struct module
*module
)
1137 /* Note: here, we can fail to get a reference */
1138 if (likely(module_is_live(module
) &&
1139 atomic_inc_not_zero(&module
->refcnt
) != 0))
1140 trace_module_get(module
, _RET_IP_
);
1148 EXPORT_SYMBOL(try_module_get
);
1150 void module_put(struct module
*module
)
1156 ret
= atomic_dec_if_positive(&module
->refcnt
);
1157 WARN_ON(ret
< 0); /* Failed to put refcount */
1158 trace_module_put(module
, _RET_IP_
);
1162 EXPORT_SYMBOL(module_put
);
1164 #else /* !CONFIG_MODULE_UNLOAD */
1165 static inline void print_unload_info(struct seq_file
*m
, struct module
*mod
)
1167 /* We don't know the usage count, or what modules are using. */
1168 seq_puts(m
, " - -");
1171 static inline void module_unload_free(struct module
*mod
)
1175 static int ref_module(struct module
*a
, struct module
*b
)
1177 return strong_try_module_get(b
);
1180 static inline int module_unload_init(struct module
*mod
)
1184 #endif /* CONFIG_MODULE_UNLOAD */
1186 static size_t module_flags_taint(struct module
*mod
, char *buf
)
1191 for (i
= 0; i
< TAINT_FLAGS_COUNT
; i
++) {
1192 if (taint_flags
[i
].module
&& test_bit(i
, &mod
->taints
))
1193 buf
[l
++] = taint_flags
[i
].c_true
;
1199 static ssize_t
show_initstate(struct module_attribute
*mattr
,
1200 struct module_kobject
*mk
, char *buffer
)
1202 const char *state
= "unknown";
1204 switch (mk
->mod
->state
) {
1205 case MODULE_STATE_LIVE
:
1208 case MODULE_STATE_COMING
:
1211 case MODULE_STATE_GOING
:
1217 return sprintf(buffer
, "%s\n", state
);
1220 static struct module_attribute modinfo_initstate
=
1221 __ATTR(initstate
, 0444, show_initstate
, NULL
);
1223 static ssize_t
store_uevent(struct module_attribute
*mattr
,
1224 struct module_kobject
*mk
,
1225 const char *buffer
, size_t count
)
1229 rc
= kobject_synth_uevent(&mk
->kobj
, buffer
, count
);
1230 return rc
? rc
: count
;
1233 struct module_attribute module_uevent
=
1234 __ATTR(uevent
, 0200, NULL
, store_uevent
);
1236 static ssize_t
show_coresize(struct module_attribute
*mattr
,
1237 struct module_kobject
*mk
, char *buffer
)
1239 return sprintf(buffer
, "%u\n", mk
->mod
->core_layout
.size
);
1242 static struct module_attribute modinfo_coresize
=
1243 __ATTR(coresize
, 0444, show_coresize
, NULL
);
1245 static ssize_t
show_initsize(struct module_attribute
*mattr
,
1246 struct module_kobject
*mk
, char *buffer
)
1248 return sprintf(buffer
, "%u\n", mk
->mod
->init_layout
.size
);
1251 static struct module_attribute modinfo_initsize
=
1252 __ATTR(initsize
, 0444, show_initsize
, NULL
);
1254 static ssize_t
show_taint(struct module_attribute
*mattr
,
1255 struct module_kobject
*mk
, char *buffer
)
1259 l
= module_flags_taint(mk
->mod
, buffer
);
1264 static struct module_attribute modinfo_taint
=
1265 __ATTR(taint
, 0444, show_taint
, NULL
);
1267 static struct module_attribute
*modinfo_attrs
[] = {
1270 &modinfo_srcversion
,
1275 #ifdef CONFIG_MODULE_UNLOAD
1281 static const char vermagic
[] = VERMAGIC_STRING
;
1283 static int try_to_force_load(struct module
*mod
, const char *reason
)
1285 #ifdef CONFIG_MODULE_FORCE_LOAD
1286 if (!test_taint(TAINT_FORCED_MODULE
))
1287 pr_warn("%s: %s: kernel tainted.\n", mod
->name
, reason
);
1288 add_taint_module(mod
, TAINT_FORCED_MODULE
, LOCKDEP_NOW_UNRELIABLE
);
1295 #ifdef CONFIG_MODVERSIONS
1297 static u32
resolve_rel_crc(const s32
*crc
)
1299 return *(u32
*)((void *)crc
+ *crc
);
1302 static int check_version(const struct load_info
*info
,
1303 const char *symname
,
1307 Elf_Shdr
*sechdrs
= info
->sechdrs
;
1308 unsigned int versindex
= info
->index
.vers
;
1309 unsigned int i
, num_versions
;
1310 struct modversion_info
*versions
;
1312 /* Exporting module didn't supply crcs? OK, we're already tainted. */
1316 /* No versions at all? modprobe --force does this. */
1318 return try_to_force_load(mod
, symname
) == 0;
1320 versions
= (void *) sechdrs
[versindex
].sh_addr
;
1321 num_versions
= sechdrs
[versindex
].sh_size
1322 / sizeof(struct modversion_info
);
1324 for (i
= 0; i
< num_versions
; i
++) {
1327 if (strcmp(versions
[i
].name
, symname
) != 0)
1330 if (IS_ENABLED(CONFIG_MODULE_REL_CRCS
))
1331 crcval
= resolve_rel_crc(crc
);
1334 if (versions
[i
].crc
== crcval
)
1336 pr_debug("Found checksum %X vs module %lX\n",
1337 crcval
, versions
[i
].crc
);
1341 /* Broken toolchain. Warn once, then let it go.. */
1342 pr_warn_once("%s: no symbol version for %s\n", info
->name
, symname
);
1346 pr_warn("%s: disagrees about version of symbol %s\n",
1347 info
->name
, symname
);
1351 static inline int check_modstruct_version(const struct load_info
*info
,
1357 * Since this should be found in kernel (which can't be removed), no
1358 * locking is necessary -- use preempt_disable() to placate lockdep.
1361 if (!find_symbol("module_layout", NULL
, &crc
, NULL
, true, false)) {
1366 return check_version(info
, "module_layout", mod
, crc
);
1369 /* First part is kernel version, which we ignore if module has crcs. */
1370 static inline int same_magic(const char *amagic
, const char *bmagic
,
1374 amagic
+= strcspn(amagic
, " ");
1375 bmagic
+= strcspn(bmagic
, " ");
1377 return strcmp(amagic
, bmagic
) == 0;
1380 static inline int check_version(const struct load_info
*info
,
1381 const char *symname
,
1388 static inline int check_modstruct_version(const struct load_info
*info
,
1394 static inline int same_magic(const char *amagic
, const char *bmagic
,
1397 return strcmp(amagic
, bmagic
) == 0;
1399 #endif /* CONFIG_MODVERSIONS */
1401 static char *get_modinfo(const struct load_info
*info
, const char *tag
);
1402 static char *get_next_modinfo(const struct load_info
*info
, const char *tag
,
1405 static int verify_namespace_is_imported(const struct load_info
*info
,
1406 const struct kernel_symbol
*sym
,
1409 const char *namespace;
1410 char *imported_namespace
;
1412 namespace = kernel_symbol_namespace(sym
);
1413 if (namespace && namespace[0]) {
1414 imported_namespace
= get_modinfo(info
, "import_ns");
1415 while (imported_namespace
) {
1416 if (strcmp(namespace, imported_namespace
) == 0)
1418 imported_namespace
= get_next_modinfo(
1419 info
, "import_ns", imported_namespace
);
1421 #ifdef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS
1426 "%s: module uses symbol (%s) from namespace %s, but does not import it.\n",
1427 mod
->name
, kernel_symbol_name(sym
), namespace);
1428 #ifndef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS
1435 static bool inherit_taint(struct module
*mod
, struct module
*owner
)
1437 if (!owner
|| !test_bit(TAINT_PROPRIETARY_MODULE
, &owner
->taints
))
1440 if (mod
->using_gplonly_symbols
) {
1441 pr_err("%s: module using GPL-only symbols uses symbols from proprietary module %s.\n",
1442 mod
->name
, owner
->name
);
1446 if (!test_bit(TAINT_PROPRIETARY_MODULE
, &mod
->taints
)) {
1447 pr_warn("%s: module uses symbols from proprietary module %s, inheriting taint.\n",
1448 mod
->name
, owner
->name
);
1449 set_bit(TAINT_PROPRIETARY_MODULE
, &mod
->taints
);
1454 /* Resolve a symbol for this module. I.e. if we find one, record usage. */
1455 static const struct kernel_symbol
*resolve_symbol(struct module
*mod
,
1456 const struct load_info
*info
,
1460 struct module
*owner
;
1461 const struct kernel_symbol
*sym
;
1463 enum mod_license license
;
1467 * The module_mutex should not be a heavily contended lock;
1468 * if we get the occasional sleep here, we'll go an extra iteration
1469 * in the wait_event_interruptible(), which is harmless.
1471 sched_annotate_sleep();
1472 mutex_lock(&module_mutex
);
1473 sym
= find_symbol(name
, &owner
, &crc
, &license
,
1474 !(mod
->taints
& (1 << TAINT_PROPRIETARY_MODULE
)), true);
1478 if (license
== GPL_ONLY
)
1479 mod
->using_gplonly_symbols
= true;
1481 if (!inherit_taint(mod
, owner
)) {
1486 if (!check_version(info
, name
, mod
, crc
)) {
1487 sym
= ERR_PTR(-EINVAL
);
1491 err
= verify_namespace_is_imported(info
, sym
, mod
);
1497 err
= ref_module(mod
, owner
);
1504 /* We must make copy under the lock if we failed to get ref. */
1505 strncpy(ownername
, module_name(owner
), MODULE_NAME_LEN
);
1507 mutex_unlock(&module_mutex
);
1511 static const struct kernel_symbol
*
1512 resolve_symbol_wait(struct module
*mod
,
1513 const struct load_info
*info
,
1516 const struct kernel_symbol
*ksym
;
1517 char owner
[MODULE_NAME_LEN
];
1519 if (wait_event_interruptible_timeout(module_wq
,
1520 !IS_ERR(ksym
= resolve_symbol(mod
, info
, name
, owner
))
1521 || PTR_ERR(ksym
) != -EBUSY
,
1523 pr_warn("%s: gave up waiting for init of module %s.\n",
1530 * /sys/module/foo/sections stuff
1531 * J. Corbet <corbet@lwn.net>
1535 #ifdef CONFIG_KALLSYMS
1536 static inline bool sect_empty(const Elf_Shdr
*sect
)
1538 return !(sect
->sh_flags
& SHF_ALLOC
) || sect
->sh_size
== 0;
1541 struct module_sect_attr
{
1542 struct bin_attribute battr
;
1543 unsigned long address
;
1546 struct module_sect_attrs
{
1547 struct attribute_group grp
;
1548 unsigned int nsections
;
1549 struct module_sect_attr attrs
[];
1552 #define MODULE_SECT_READ_SIZE (3 /* "0x", "\n" */ + (BITS_PER_LONG / 4))
1553 static ssize_t
module_sect_read(struct file
*file
, struct kobject
*kobj
,
1554 struct bin_attribute
*battr
,
1555 char *buf
, loff_t pos
, size_t count
)
1557 struct module_sect_attr
*sattr
=
1558 container_of(battr
, struct module_sect_attr
, battr
);
1559 char bounce
[MODULE_SECT_READ_SIZE
+ 1];
1566 * Since we're a binary read handler, we must account for the
1567 * trailing NUL byte that sprintf will write: if "buf" is
1568 * too small to hold the NUL, or the NUL is exactly the last
1569 * byte, the read will look like it got truncated by one byte.
1570 * Since there is no way to ask sprintf nicely to not write
1571 * the NUL, we have to use a bounce buffer.
1573 wrote
= scnprintf(bounce
, sizeof(bounce
), "0x%px\n",
1574 kallsyms_show_value(file
->f_cred
)
1575 ? (void *)sattr
->address
: NULL
);
1576 count
= min(count
, wrote
);
1577 memcpy(buf
, bounce
, count
);
1582 static void free_sect_attrs(struct module_sect_attrs
*sect_attrs
)
1584 unsigned int section
;
1586 for (section
= 0; section
< sect_attrs
->nsections
; section
++)
1587 kfree(sect_attrs
->attrs
[section
].battr
.attr
.name
);
1591 static void add_sect_attrs(struct module
*mod
, const struct load_info
*info
)
1593 unsigned int nloaded
= 0, i
, size
[2];
1594 struct module_sect_attrs
*sect_attrs
;
1595 struct module_sect_attr
*sattr
;
1596 struct bin_attribute
**gattr
;
1598 /* Count loaded sections and allocate structures */
1599 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
1600 if (!sect_empty(&info
->sechdrs
[i
]))
1602 size
[0] = ALIGN(struct_size(sect_attrs
, attrs
, nloaded
),
1603 sizeof(sect_attrs
->grp
.bin_attrs
[0]));
1604 size
[1] = (nloaded
+ 1) * sizeof(sect_attrs
->grp
.bin_attrs
[0]);
1605 sect_attrs
= kzalloc(size
[0] + size
[1], GFP_KERNEL
);
1606 if (sect_attrs
== NULL
)
1609 /* Setup section attributes. */
1610 sect_attrs
->grp
.name
= "sections";
1611 sect_attrs
->grp
.bin_attrs
= (void *)sect_attrs
+ size
[0];
1613 sect_attrs
->nsections
= 0;
1614 sattr
= §_attrs
->attrs
[0];
1615 gattr
= §_attrs
->grp
.bin_attrs
[0];
1616 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++) {
1617 Elf_Shdr
*sec
= &info
->sechdrs
[i
];
1618 if (sect_empty(sec
))
1620 sysfs_bin_attr_init(&sattr
->battr
);
1621 sattr
->address
= sec
->sh_addr
;
1622 sattr
->battr
.attr
.name
=
1623 kstrdup(info
->secstrings
+ sec
->sh_name
, GFP_KERNEL
);
1624 if (sattr
->battr
.attr
.name
== NULL
)
1626 sect_attrs
->nsections
++;
1627 sattr
->battr
.read
= module_sect_read
;
1628 sattr
->battr
.size
= MODULE_SECT_READ_SIZE
;
1629 sattr
->battr
.attr
.mode
= 0400;
1630 *(gattr
++) = &(sattr
++)->battr
;
1634 if (sysfs_create_group(&mod
->mkobj
.kobj
, §_attrs
->grp
))
1637 mod
->sect_attrs
= sect_attrs
;
1640 free_sect_attrs(sect_attrs
);
1643 static void remove_sect_attrs(struct module
*mod
)
1645 if (mod
->sect_attrs
) {
1646 sysfs_remove_group(&mod
->mkobj
.kobj
,
1647 &mod
->sect_attrs
->grp
);
1648 /* We are positive that no one is using any sect attrs
1649 * at this point. Deallocate immediately. */
1650 free_sect_attrs(mod
->sect_attrs
);
1651 mod
->sect_attrs
= NULL
;
1656 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1659 struct module_notes_attrs
{
1660 struct kobject
*dir
;
1662 struct bin_attribute attrs
[];
1665 static ssize_t
module_notes_read(struct file
*filp
, struct kobject
*kobj
,
1666 struct bin_attribute
*bin_attr
,
1667 char *buf
, loff_t pos
, size_t count
)
1670 * The caller checked the pos and count against our size.
1672 memcpy(buf
, bin_attr
->private + pos
, count
);
1676 static void free_notes_attrs(struct module_notes_attrs
*notes_attrs
,
1679 if (notes_attrs
->dir
) {
1681 sysfs_remove_bin_file(notes_attrs
->dir
,
1682 ¬es_attrs
->attrs
[i
]);
1683 kobject_put(notes_attrs
->dir
);
1688 static void add_notes_attrs(struct module
*mod
, const struct load_info
*info
)
1690 unsigned int notes
, loaded
, i
;
1691 struct module_notes_attrs
*notes_attrs
;
1692 struct bin_attribute
*nattr
;
1694 /* failed to create section attributes, so can't create notes */
1695 if (!mod
->sect_attrs
)
1698 /* Count notes sections and allocate structures. */
1700 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
1701 if (!sect_empty(&info
->sechdrs
[i
]) &&
1702 (info
->sechdrs
[i
].sh_type
== SHT_NOTE
))
1708 notes_attrs
= kzalloc(struct_size(notes_attrs
, attrs
, notes
),
1710 if (notes_attrs
== NULL
)
1713 notes_attrs
->notes
= notes
;
1714 nattr
= ¬es_attrs
->attrs
[0];
1715 for (loaded
= i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
1716 if (sect_empty(&info
->sechdrs
[i
]))
1718 if (info
->sechdrs
[i
].sh_type
== SHT_NOTE
) {
1719 sysfs_bin_attr_init(nattr
);
1720 nattr
->attr
.name
= mod
->sect_attrs
->attrs
[loaded
].battr
.attr
.name
;
1721 nattr
->attr
.mode
= S_IRUGO
;
1722 nattr
->size
= info
->sechdrs
[i
].sh_size
;
1723 nattr
->private = (void *) info
->sechdrs
[i
].sh_addr
;
1724 nattr
->read
= module_notes_read
;
1730 notes_attrs
->dir
= kobject_create_and_add("notes", &mod
->mkobj
.kobj
);
1731 if (!notes_attrs
->dir
)
1734 for (i
= 0; i
< notes
; ++i
)
1735 if (sysfs_create_bin_file(notes_attrs
->dir
,
1736 ¬es_attrs
->attrs
[i
]))
1739 mod
->notes_attrs
= notes_attrs
;
1743 free_notes_attrs(notes_attrs
, i
);
1746 static void remove_notes_attrs(struct module
*mod
)
1748 if (mod
->notes_attrs
)
1749 free_notes_attrs(mod
->notes_attrs
, mod
->notes_attrs
->notes
);
1754 static inline void add_sect_attrs(struct module
*mod
,
1755 const struct load_info
*info
)
1759 static inline void remove_sect_attrs(struct module
*mod
)
1763 static inline void add_notes_attrs(struct module
*mod
,
1764 const struct load_info
*info
)
1768 static inline void remove_notes_attrs(struct module
*mod
)
1771 #endif /* CONFIG_KALLSYMS */
1773 static void del_usage_links(struct module
*mod
)
1775 #ifdef CONFIG_MODULE_UNLOAD
1776 struct module_use
*use
;
1778 mutex_lock(&module_mutex
);
1779 list_for_each_entry(use
, &mod
->target_list
, target_list
)
1780 sysfs_remove_link(use
->target
->holders_dir
, mod
->name
);
1781 mutex_unlock(&module_mutex
);
1785 static int add_usage_links(struct module
*mod
)
1788 #ifdef CONFIG_MODULE_UNLOAD
1789 struct module_use
*use
;
1791 mutex_lock(&module_mutex
);
1792 list_for_each_entry(use
, &mod
->target_list
, target_list
) {
1793 ret
= sysfs_create_link(use
->target
->holders_dir
,
1794 &mod
->mkobj
.kobj
, mod
->name
);
1798 mutex_unlock(&module_mutex
);
1800 del_usage_links(mod
);
1805 static void module_remove_modinfo_attrs(struct module
*mod
, int end
);
1807 static int module_add_modinfo_attrs(struct module
*mod
)
1809 struct module_attribute
*attr
;
1810 struct module_attribute
*temp_attr
;
1814 mod
->modinfo_attrs
= kzalloc((sizeof(struct module_attribute
) *
1815 (ARRAY_SIZE(modinfo_attrs
) + 1)),
1817 if (!mod
->modinfo_attrs
)
1820 temp_attr
= mod
->modinfo_attrs
;
1821 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
1822 if (!attr
->test
|| attr
->test(mod
)) {
1823 memcpy(temp_attr
, attr
, sizeof(*temp_attr
));
1824 sysfs_attr_init(&temp_attr
->attr
);
1825 error
= sysfs_create_file(&mod
->mkobj
.kobj
,
1837 module_remove_modinfo_attrs(mod
, --i
);
1839 kfree(mod
->modinfo_attrs
);
1843 static void module_remove_modinfo_attrs(struct module
*mod
, int end
)
1845 struct module_attribute
*attr
;
1848 for (i
= 0; (attr
= &mod
->modinfo_attrs
[i
]); i
++) {
1849 if (end
>= 0 && i
> end
)
1851 /* pick a field to test for end of list */
1852 if (!attr
->attr
.name
)
1854 sysfs_remove_file(&mod
->mkobj
.kobj
, &attr
->attr
);
1858 kfree(mod
->modinfo_attrs
);
1861 static void mod_kobject_put(struct module
*mod
)
1863 DECLARE_COMPLETION_ONSTACK(c
);
1864 mod
->mkobj
.kobj_completion
= &c
;
1865 kobject_put(&mod
->mkobj
.kobj
);
1866 wait_for_completion(&c
);
1869 static int mod_sysfs_init(struct module
*mod
)
1872 struct kobject
*kobj
;
1874 if (!module_sysfs_initialized
) {
1875 pr_err("%s: module sysfs not initialized\n", mod
->name
);
1880 kobj
= kset_find_obj(module_kset
, mod
->name
);
1882 pr_err("%s: module is already loaded\n", mod
->name
);
1888 mod
->mkobj
.mod
= mod
;
1890 memset(&mod
->mkobj
.kobj
, 0, sizeof(mod
->mkobj
.kobj
));
1891 mod
->mkobj
.kobj
.kset
= module_kset
;
1892 err
= kobject_init_and_add(&mod
->mkobj
.kobj
, &module_ktype
, NULL
,
1895 mod_kobject_put(mod
);
1897 /* delay uevent until full sysfs population */
1902 static int mod_sysfs_setup(struct module
*mod
,
1903 const struct load_info
*info
,
1904 struct kernel_param
*kparam
,
1905 unsigned int num_params
)
1909 err
= mod_sysfs_init(mod
);
1913 mod
->holders_dir
= kobject_create_and_add("holders", &mod
->mkobj
.kobj
);
1914 if (!mod
->holders_dir
) {
1919 err
= module_param_sysfs_setup(mod
, kparam
, num_params
);
1921 goto out_unreg_holders
;
1923 err
= module_add_modinfo_attrs(mod
);
1925 goto out_unreg_param
;
1927 err
= add_usage_links(mod
);
1929 goto out_unreg_modinfo_attrs
;
1931 add_sect_attrs(mod
, info
);
1932 add_notes_attrs(mod
, info
);
1934 kobject_uevent(&mod
->mkobj
.kobj
, KOBJ_ADD
);
1937 out_unreg_modinfo_attrs
:
1938 module_remove_modinfo_attrs(mod
, -1);
1940 module_param_sysfs_remove(mod
);
1942 kobject_put(mod
->holders_dir
);
1944 mod_kobject_put(mod
);
1949 static void mod_sysfs_fini(struct module
*mod
)
1951 remove_notes_attrs(mod
);
1952 remove_sect_attrs(mod
);
1953 mod_kobject_put(mod
);
1956 static void init_param_lock(struct module
*mod
)
1958 mutex_init(&mod
->param_lock
);
1960 #else /* !CONFIG_SYSFS */
1962 static int mod_sysfs_setup(struct module
*mod
,
1963 const struct load_info
*info
,
1964 struct kernel_param
*kparam
,
1965 unsigned int num_params
)
1970 static void mod_sysfs_fini(struct module
*mod
)
1974 static void module_remove_modinfo_attrs(struct module
*mod
, int end
)
1978 static void del_usage_links(struct module
*mod
)
1982 static void init_param_lock(struct module
*mod
)
1985 #endif /* CONFIG_SYSFS */
1987 static void mod_sysfs_teardown(struct module
*mod
)
1989 del_usage_links(mod
);
1990 module_remove_modinfo_attrs(mod
, -1);
1991 module_param_sysfs_remove(mod
);
1992 kobject_put(mod
->mkobj
.drivers_dir
);
1993 kobject_put(mod
->holders_dir
);
1994 mod_sysfs_fini(mod
);
1998 * LKM RO/NX protection: protect module's text/ro-data
1999 * from modification and any data from execution.
2001 * General layout of module is:
2002 * [text] [read-only-data] [ro-after-init] [writable data]
2003 * text_size -----^ ^ ^ ^
2004 * ro_size ------------------------| | |
2005 * ro_after_init_size -----------------------------| |
2006 * size -----------------------------------------------------------|
2008 * These values are always page-aligned (as is base)
2012 * Since some arches are moving towards PAGE_KERNEL module allocations instead
2013 * of PAGE_KERNEL_EXEC, keep frob_text() and module_enable_x() outside of the
2014 * CONFIG_STRICT_MODULE_RWX block below because they are needed regardless of
2015 * whether we are strict.
2017 #ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX
2018 static void frob_text(const struct module_layout
*layout
,
2019 int (*set_memory
)(unsigned long start
, int num_pages
))
2021 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
2022 BUG_ON((unsigned long)layout
->text_size
& (PAGE_SIZE
-1));
2023 set_memory((unsigned long)layout
->base
,
2024 layout
->text_size
>> PAGE_SHIFT
);
2027 static void module_enable_x(const struct module
*mod
)
2029 frob_text(&mod
->core_layout
, set_memory_x
);
2030 frob_text(&mod
->init_layout
, set_memory_x
);
2032 #else /* !CONFIG_ARCH_HAS_STRICT_MODULE_RWX */
2033 static void module_enable_x(const struct module
*mod
) { }
2034 #endif /* CONFIG_ARCH_HAS_STRICT_MODULE_RWX */
2036 #ifdef CONFIG_STRICT_MODULE_RWX
2037 static void frob_rodata(const struct module_layout
*layout
,
2038 int (*set_memory
)(unsigned long start
, int num_pages
))
2040 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
2041 BUG_ON((unsigned long)layout
->text_size
& (PAGE_SIZE
-1));
2042 BUG_ON((unsigned long)layout
->ro_size
& (PAGE_SIZE
-1));
2043 set_memory((unsigned long)layout
->base
+ layout
->text_size
,
2044 (layout
->ro_size
- layout
->text_size
) >> PAGE_SHIFT
);
2047 static void frob_ro_after_init(const struct module_layout
*layout
,
2048 int (*set_memory
)(unsigned long start
, int num_pages
))
2050 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
2051 BUG_ON((unsigned long)layout
->ro_size
& (PAGE_SIZE
-1));
2052 BUG_ON((unsigned long)layout
->ro_after_init_size
& (PAGE_SIZE
-1));
2053 set_memory((unsigned long)layout
->base
+ layout
->ro_size
,
2054 (layout
->ro_after_init_size
- layout
->ro_size
) >> PAGE_SHIFT
);
2057 static void frob_writable_data(const struct module_layout
*layout
,
2058 int (*set_memory
)(unsigned long start
, int num_pages
))
2060 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
2061 BUG_ON((unsigned long)layout
->ro_after_init_size
& (PAGE_SIZE
-1));
2062 BUG_ON((unsigned long)layout
->size
& (PAGE_SIZE
-1));
2063 set_memory((unsigned long)layout
->base
+ layout
->ro_after_init_size
,
2064 (layout
->size
- layout
->ro_after_init_size
) >> PAGE_SHIFT
);
2067 static void module_enable_ro(const struct module
*mod
, bool after_init
)
2069 if (!rodata_enabled
)
2072 set_vm_flush_reset_perms(mod
->core_layout
.base
);
2073 set_vm_flush_reset_perms(mod
->init_layout
.base
);
2074 frob_text(&mod
->core_layout
, set_memory_ro
);
2076 frob_rodata(&mod
->core_layout
, set_memory_ro
);
2077 frob_text(&mod
->init_layout
, set_memory_ro
);
2078 frob_rodata(&mod
->init_layout
, set_memory_ro
);
2081 frob_ro_after_init(&mod
->core_layout
, set_memory_ro
);
2084 static void module_enable_nx(const struct module
*mod
)
2086 frob_rodata(&mod
->core_layout
, set_memory_nx
);
2087 frob_ro_after_init(&mod
->core_layout
, set_memory_nx
);
2088 frob_writable_data(&mod
->core_layout
, set_memory_nx
);
2089 frob_rodata(&mod
->init_layout
, set_memory_nx
);
2090 frob_writable_data(&mod
->init_layout
, set_memory_nx
);
2093 static int module_enforce_rwx_sections(Elf_Ehdr
*hdr
, Elf_Shdr
*sechdrs
,
2094 char *secstrings
, struct module
*mod
)
2096 const unsigned long shf_wx
= SHF_WRITE
|SHF_EXECINSTR
;
2099 for (i
= 0; i
< hdr
->e_shnum
; i
++) {
2100 if ((sechdrs
[i
].sh_flags
& shf_wx
) == shf_wx
)
2107 #else /* !CONFIG_STRICT_MODULE_RWX */
2108 static void module_enable_nx(const struct module
*mod
) { }
2109 static void module_enable_ro(const struct module
*mod
, bool after_init
) {}
2110 static int module_enforce_rwx_sections(Elf_Ehdr
*hdr
, Elf_Shdr
*sechdrs
,
2111 char *secstrings
, struct module
*mod
)
2115 #endif /* CONFIG_STRICT_MODULE_RWX */
2117 #ifdef CONFIG_LIVEPATCH
2119 * Persist Elf information about a module. Copy the Elf header,
2120 * section header table, section string table, and symtab section
2121 * index from info to mod->klp_info.
2123 static int copy_module_elf(struct module
*mod
, struct load_info
*info
)
2125 unsigned int size
, symndx
;
2128 size
= sizeof(*mod
->klp_info
);
2129 mod
->klp_info
= kmalloc(size
, GFP_KERNEL
);
2130 if (mod
->klp_info
== NULL
)
2134 size
= sizeof(mod
->klp_info
->hdr
);
2135 memcpy(&mod
->klp_info
->hdr
, info
->hdr
, size
);
2137 /* Elf section header table */
2138 size
= sizeof(*info
->sechdrs
) * info
->hdr
->e_shnum
;
2139 mod
->klp_info
->sechdrs
= kmemdup(info
->sechdrs
, size
, GFP_KERNEL
);
2140 if (mod
->klp_info
->sechdrs
== NULL
) {
2145 /* Elf section name string table */
2146 size
= info
->sechdrs
[info
->hdr
->e_shstrndx
].sh_size
;
2147 mod
->klp_info
->secstrings
= kmemdup(info
->secstrings
, size
, GFP_KERNEL
);
2148 if (mod
->klp_info
->secstrings
== NULL
) {
2153 /* Elf symbol section index */
2154 symndx
= info
->index
.sym
;
2155 mod
->klp_info
->symndx
= symndx
;
2158 * For livepatch modules, core_kallsyms.symtab is a complete
2159 * copy of the original symbol table. Adjust sh_addr to point
2160 * to core_kallsyms.symtab since the copy of the symtab in module
2161 * init memory is freed at the end of do_init_module().
2163 mod
->klp_info
->sechdrs
[symndx
].sh_addr
= \
2164 (unsigned long) mod
->core_kallsyms
.symtab
;
2169 kfree(mod
->klp_info
->sechdrs
);
2171 kfree(mod
->klp_info
);
2175 static void free_module_elf(struct module
*mod
)
2177 kfree(mod
->klp_info
->sechdrs
);
2178 kfree(mod
->klp_info
->secstrings
);
2179 kfree(mod
->klp_info
);
2181 #else /* !CONFIG_LIVEPATCH */
2182 static int copy_module_elf(struct module
*mod
, struct load_info
*info
)
2187 static void free_module_elf(struct module
*mod
)
2190 #endif /* CONFIG_LIVEPATCH */
2192 void __weak
module_memfree(void *module_region
)
2195 * This memory may be RO, and freeing RO memory in an interrupt is not
2196 * supported by vmalloc.
2198 WARN_ON(in_interrupt());
2199 vfree(module_region
);
2202 void __weak
module_arch_cleanup(struct module
*mod
)
2206 void __weak
module_arch_freeing_init(struct module
*mod
)
2210 /* Free a module, remove from lists, etc. */
2211 static void free_module(struct module
*mod
)
2213 trace_module_free(mod
);
2215 mod_sysfs_teardown(mod
);
2217 /* We leave it in list to prevent duplicate loads, but make sure
2218 * that noone uses it while it's being deconstructed. */
2219 mutex_lock(&module_mutex
);
2220 mod
->state
= MODULE_STATE_UNFORMED
;
2221 mutex_unlock(&module_mutex
);
2223 /* Remove dynamic debug info */
2224 ddebug_remove_module(mod
->name
);
2226 /* Arch-specific cleanup. */
2227 module_arch_cleanup(mod
);
2229 /* Module unload stuff */
2230 module_unload_free(mod
);
2232 /* Free any allocated parameters. */
2233 destroy_params(mod
->kp
, mod
->num_kp
);
2235 if (is_livepatch_module(mod
))
2236 free_module_elf(mod
);
2238 /* Now we can delete it from the lists */
2239 mutex_lock(&module_mutex
);
2240 /* Unlink carefully: kallsyms could be walking list. */
2241 list_del_rcu(&mod
->list
);
2242 mod_tree_remove(mod
);
2243 /* Remove this module from bug list, this uses list_del_rcu */
2244 module_bug_cleanup(mod
);
2245 /* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */
2247 mutex_unlock(&module_mutex
);
2249 /* This may be empty, but that's OK */
2250 module_arch_freeing_init(mod
);
2251 module_memfree(mod
->init_layout
.base
);
2253 percpu_modfree(mod
);
2255 /* Free lock-classes; relies on the preceding sync_rcu(). */
2256 lockdep_free_key_range(mod
->core_layout
.base
, mod
->core_layout
.size
);
2258 /* Finally, free the core (containing the module structure) */
2259 module_memfree(mod
->core_layout
.base
);
2262 void *__symbol_get(const char *symbol
)
2264 struct module
*owner
;
2265 const struct kernel_symbol
*sym
;
2268 sym
= find_symbol(symbol
, &owner
, NULL
, NULL
, true, true);
2269 if (sym
&& strong_try_module_get(owner
))
2273 return sym
? (void *)kernel_symbol_value(sym
) : NULL
;
2275 EXPORT_SYMBOL_GPL(__symbol_get
);
2278 * Ensure that an exported symbol [global namespace] does not already exist
2279 * in the kernel or in some other module's exported symbol table.
2281 * You must hold the module_mutex.
2283 static int verify_exported_symbols(struct module
*mod
)
2286 struct module
*owner
;
2287 const struct kernel_symbol
*s
;
2289 const struct kernel_symbol
*sym
;
2292 { mod
->syms
, mod
->num_syms
},
2293 { mod
->gpl_syms
, mod
->num_gpl_syms
},
2294 { mod
->gpl_future_syms
, mod
->num_gpl_future_syms
},
2295 #ifdef CONFIG_UNUSED_SYMBOLS
2296 { mod
->unused_syms
, mod
->num_unused_syms
},
2297 { mod
->unused_gpl_syms
, mod
->num_unused_gpl_syms
},
2301 for (i
= 0; i
< ARRAY_SIZE(arr
); i
++) {
2302 for (s
= arr
[i
].sym
; s
< arr
[i
].sym
+ arr
[i
].num
; s
++) {
2303 if (find_symbol(kernel_symbol_name(s
), &owner
, NULL
,
2304 NULL
, true, false)) {
2305 pr_err("%s: exports duplicate symbol %s"
2307 mod
->name
, kernel_symbol_name(s
),
2308 module_name(owner
));
2316 /* Change all symbols so that st_value encodes the pointer directly. */
2317 static int simplify_symbols(struct module
*mod
, const struct load_info
*info
)
2319 Elf_Shdr
*symsec
= &info
->sechdrs
[info
->index
.sym
];
2320 Elf_Sym
*sym
= (void *)symsec
->sh_addr
;
2321 unsigned long secbase
;
2324 const struct kernel_symbol
*ksym
;
2326 for (i
= 1; i
< symsec
->sh_size
/ sizeof(Elf_Sym
); i
++) {
2327 const char *name
= info
->strtab
+ sym
[i
].st_name
;
2329 switch (sym
[i
].st_shndx
) {
2331 /* Ignore common symbols */
2332 if (!strncmp(name
, "__gnu_lto", 9))
2335 /* We compiled with -fno-common. These are not
2336 supposed to happen. */
2337 pr_debug("Common symbol: %s\n", name
);
2338 pr_warn("%s: please compile with -fno-common\n",
2344 /* Don't need to do anything */
2345 pr_debug("Absolute symbol: 0x%08lx\n",
2346 (long)sym
[i
].st_value
);
2350 /* Livepatch symbols are resolved by livepatch */
2354 ksym
= resolve_symbol_wait(mod
, info
, name
);
2355 /* Ok if resolved. */
2356 if (ksym
&& !IS_ERR(ksym
)) {
2357 sym
[i
].st_value
= kernel_symbol_value(ksym
);
2362 if (!ksym
&& ELF_ST_BIND(sym
[i
].st_info
) == STB_WEAK
)
2365 ret
= PTR_ERR(ksym
) ?: -ENOENT
;
2366 pr_warn("%s: Unknown symbol %s (err %d)\n",
2367 mod
->name
, name
, ret
);
2371 /* Divert to percpu allocation if a percpu var. */
2372 if (sym
[i
].st_shndx
== info
->index
.pcpu
)
2373 secbase
= (unsigned long)mod_percpu(mod
);
2375 secbase
= info
->sechdrs
[sym
[i
].st_shndx
].sh_addr
;
2376 sym
[i
].st_value
+= secbase
;
2384 static int apply_relocations(struct module
*mod
, const struct load_info
*info
)
2389 /* Now do relocations. */
2390 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2391 unsigned int infosec
= info
->sechdrs
[i
].sh_info
;
2393 /* Not a valid relocation section? */
2394 if (infosec
>= info
->hdr
->e_shnum
)
2397 /* Don't bother with non-allocated sections */
2398 if (!(info
->sechdrs
[infosec
].sh_flags
& SHF_ALLOC
))
2401 if (info
->sechdrs
[i
].sh_flags
& SHF_RELA_LIVEPATCH
)
2402 err
= klp_apply_section_relocs(mod
, info
->sechdrs
,
2407 else if (info
->sechdrs
[i
].sh_type
== SHT_REL
)
2408 err
= apply_relocate(info
->sechdrs
, info
->strtab
,
2409 info
->index
.sym
, i
, mod
);
2410 else if (info
->sechdrs
[i
].sh_type
== SHT_RELA
)
2411 err
= apply_relocate_add(info
->sechdrs
, info
->strtab
,
2412 info
->index
.sym
, i
, mod
);
2419 /* Additional bytes needed by arch in front of individual sections */
2420 unsigned int __weak
arch_mod_section_prepend(struct module
*mod
,
2421 unsigned int section
)
2423 /* default implementation just returns zero */
2427 /* Update size with this section: return offset. */
2428 static long get_offset(struct module
*mod
, unsigned int *size
,
2429 Elf_Shdr
*sechdr
, unsigned int section
)
2433 *size
+= arch_mod_section_prepend(mod
, section
);
2434 ret
= ALIGN(*size
, sechdr
->sh_addralign
?: 1);
2435 *size
= ret
+ sechdr
->sh_size
;
2439 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
2440 might -- code, read-only data, read-write data, small data. Tally
2441 sizes, and place the offsets into sh_entsize fields: high bit means it
2443 static void layout_sections(struct module
*mod
, struct load_info
*info
)
2445 static unsigned long const masks
[][2] = {
2446 /* NOTE: all executable code must be the first section
2447 * in this array; otherwise modify the text_size
2448 * finder in the two loops below */
2449 { SHF_EXECINSTR
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2450 { SHF_ALLOC
, SHF_WRITE
| ARCH_SHF_SMALL
},
2451 { SHF_RO_AFTER_INIT
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2452 { SHF_WRITE
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2453 { ARCH_SHF_SMALL
| SHF_ALLOC
, 0 }
2457 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
2458 info
->sechdrs
[i
].sh_entsize
= ~0UL;
2460 pr_debug("Core section allocation order:\n");
2461 for (m
= 0; m
< ARRAY_SIZE(masks
); ++m
) {
2462 for (i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
2463 Elf_Shdr
*s
= &info
->sechdrs
[i
];
2464 const char *sname
= info
->secstrings
+ s
->sh_name
;
2466 if ((s
->sh_flags
& masks
[m
][0]) != masks
[m
][0]
2467 || (s
->sh_flags
& masks
[m
][1])
2468 || s
->sh_entsize
!= ~0UL
2469 || module_init_section(sname
))
2471 s
->sh_entsize
= get_offset(mod
, &mod
->core_layout
.size
, s
, i
);
2472 pr_debug("\t%s\n", sname
);
2475 case 0: /* executable */
2476 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2477 mod
->core_layout
.text_size
= mod
->core_layout
.size
;
2479 case 1: /* RO: text and ro-data */
2480 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2481 mod
->core_layout
.ro_size
= mod
->core_layout
.size
;
2483 case 2: /* RO after init */
2484 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2485 mod
->core_layout
.ro_after_init_size
= mod
->core_layout
.size
;
2487 case 4: /* whole core */
2488 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2493 pr_debug("Init section allocation order:\n");
2494 for (m
= 0; m
< ARRAY_SIZE(masks
); ++m
) {
2495 for (i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
2496 Elf_Shdr
*s
= &info
->sechdrs
[i
];
2497 const char *sname
= info
->secstrings
+ s
->sh_name
;
2499 if ((s
->sh_flags
& masks
[m
][0]) != masks
[m
][0]
2500 || (s
->sh_flags
& masks
[m
][1])
2501 || s
->sh_entsize
!= ~0UL
2502 || !module_init_section(sname
))
2504 s
->sh_entsize
= (get_offset(mod
, &mod
->init_layout
.size
, s
, i
)
2505 | INIT_OFFSET_MASK
);
2506 pr_debug("\t%s\n", sname
);
2509 case 0: /* executable */
2510 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2511 mod
->init_layout
.text_size
= mod
->init_layout
.size
;
2513 case 1: /* RO: text and ro-data */
2514 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2515 mod
->init_layout
.ro_size
= mod
->init_layout
.size
;
2519 * RO after init doesn't apply to init_layout (only
2520 * core_layout), so it just takes the value of ro_size.
2522 mod
->init_layout
.ro_after_init_size
= mod
->init_layout
.ro_size
;
2524 case 4: /* whole init */
2525 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2531 static void set_license(struct module
*mod
, const char *license
)
2534 license
= "unspecified";
2536 if (!license_is_gpl_compatible(license
)) {
2537 if (!test_taint(TAINT_PROPRIETARY_MODULE
))
2538 pr_warn("%s: module license '%s' taints kernel.\n",
2539 mod
->name
, license
);
2540 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
2541 LOCKDEP_NOW_UNRELIABLE
);
2545 /* Parse tag=value strings from .modinfo section */
2546 static char *next_string(char *string
, unsigned long *secsize
)
2548 /* Skip non-zero chars */
2551 if ((*secsize
)-- <= 1)
2555 /* Skip any zero padding. */
2556 while (!string
[0]) {
2558 if ((*secsize
)-- <= 1)
2564 static char *get_next_modinfo(const struct load_info
*info
, const char *tag
,
2568 unsigned int taglen
= strlen(tag
);
2569 Elf_Shdr
*infosec
= &info
->sechdrs
[info
->index
.info
];
2570 unsigned long size
= infosec
->sh_size
;
2573 * get_modinfo() calls made before rewrite_section_headers()
2574 * must use sh_offset, as sh_addr isn't set!
2576 char *modinfo
= (char *)info
->hdr
+ infosec
->sh_offset
;
2579 size
-= prev
- modinfo
;
2580 modinfo
= next_string(prev
, &size
);
2583 for (p
= modinfo
; p
; p
= next_string(p
, &size
)) {
2584 if (strncmp(p
, tag
, taglen
) == 0 && p
[taglen
] == '=')
2585 return p
+ taglen
+ 1;
2590 static char *get_modinfo(const struct load_info
*info
, const char *tag
)
2592 return get_next_modinfo(info
, tag
, NULL
);
2595 static void setup_modinfo(struct module
*mod
, struct load_info
*info
)
2597 struct module_attribute
*attr
;
2600 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
2602 attr
->setup(mod
, get_modinfo(info
, attr
->attr
.name
));
2606 static void free_modinfo(struct module
*mod
)
2608 struct module_attribute
*attr
;
2611 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
2617 #ifdef CONFIG_KALLSYMS
2619 /* Lookup exported symbol in given range of kernel_symbols */
2620 static const struct kernel_symbol
*lookup_exported_symbol(const char *name
,
2621 const struct kernel_symbol
*start
,
2622 const struct kernel_symbol
*stop
)
2624 return bsearch(name
, start
, stop
- start
,
2625 sizeof(struct kernel_symbol
), cmp_name
);
2628 static int is_exported(const char *name
, unsigned long value
,
2629 const struct module
*mod
)
2631 const struct kernel_symbol
*ks
;
2633 ks
= lookup_exported_symbol(name
, __start___ksymtab
, __stop___ksymtab
);
2635 ks
= lookup_exported_symbol(name
, mod
->syms
, mod
->syms
+ mod
->num_syms
);
2637 return ks
!= NULL
&& kernel_symbol_value(ks
) == value
;
2641 static char elf_type(const Elf_Sym
*sym
, const struct load_info
*info
)
2643 const Elf_Shdr
*sechdrs
= info
->sechdrs
;
2645 if (ELF_ST_BIND(sym
->st_info
) == STB_WEAK
) {
2646 if (ELF_ST_TYPE(sym
->st_info
) == STT_OBJECT
)
2651 if (sym
->st_shndx
== SHN_UNDEF
)
2653 if (sym
->st_shndx
== SHN_ABS
|| sym
->st_shndx
== info
->index
.pcpu
)
2655 if (sym
->st_shndx
>= SHN_LORESERVE
)
2657 if (sechdrs
[sym
->st_shndx
].sh_flags
& SHF_EXECINSTR
)
2659 if (sechdrs
[sym
->st_shndx
].sh_flags
& SHF_ALLOC
2660 && sechdrs
[sym
->st_shndx
].sh_type
!= SHT_NOBITS
) {
2661 if (!(sechdrs
[sym
->st_shndx
].sh_flags
& SHF_WRITE
))
2663 else if (sechdrs
[sym
->st_shndx
].sh_flags
& ARCH_SHF_SMALL
)
2668 if (sechdrs
[sym
->st_shndx
].sh_type
== SHT_NOBITS
) {
2669 if (sechdrs
[sym
->st_shndx
].sh_flags
& ARCH_SHF_SMALL
)
2674 if (strstarts(info
->secstrings
+ sechdrs
[sym
->st_shndx
].sh_name
,
2681 static bool is_core_symbol(const Elf_Sym
*src
, const Elf_Shdr
*sechdrs
,
2682 unsigned int shnum
, unsigned int pcpundx
)
2684 const Elf_Shdr
*sec
;
2686 if (src
->st_shndx
== SHN_UNDEF
2687 || src
->st_shndx
>= shnum
2691 #ifdef CONFIG_KALLSYMS_ALL
2692 if (src
->st_shndx
== pcpundx
)
2696 sec
= sechdrs
+ src
->st_shndx
;
2697 if (!(sec
->sh_flags
& SHF_ALLOC
)
2698 #ifndef CONFIG_KALLSYMS_ALL
2699 || !(sec
->sh_flags
& SHF_EXECINSTR
)
2701 || (sec
->sh_entsize
& INIT_OFFSET_MASK
))
2708 * We only allocate and copy the strings needed by the parts of symtab
2709 * we keep. This is simple, but has the effect of making multiple
2710 * copies of duplicates. We could be more sophisticated, see
2711 * linux-kernel thread starting with
2712 * <73defb5e4bca04a6431392cc341112b1@localhost>.
2714 static void layout_symtab(struct module
*mod
, struct load_info
*info
)
2716 Elf_Shdr
*symsect
= info
->sechdrs
+ info
->index
.sym
;
2717 Elf_Shdr
*strsect
= info
->sechdrs
+ info
->index
.str
;
2719 unsigned int i
, nsrc
, ndst
, strtab_size
= 0;
2721 /* Put symbol section at end of init part of module. */
2722 symsect
->sh_flags
|= SHF_ALLOC
;
2723 symsect
->sh_entsize
= get_offset(mod
, &mod
->init_layout
.size
, symsect
,
2724 info
->index
.sym
) | INIT_OFFSET_MASK
;
2725 pr_debug("\t%s\n", info
->secstrings
+ symsect
->sh_name
);
2727 src
= (void *)info
->hdr
+ symsect
->sh_offset
;
2728 nsrc
= symsect
->sh_size
/ sizeof(*src
);
2730 /* Compute total space required for the core symbols' strtab. */
2731 for (ndst
= i
= 0; i
< nsrc
; i
++) {
2732 if (i
== 0 || is_livepatch_module(mod
) ||
2733 is_core_symbol(src
+i
, info
->sechdrs
, info
->hdr
->e_shnum
,
2734 info
->index
.pcpu
)) {
2735 strtab_size
+= strlen(&info
->strtab
[src
[i
].st_name
])+1;
2740 /* Append room for core symbols at end of core part. */
2741 info
->symoffs
= ALIGN(mod
->core_layout
.size
, symsect
->sh_addralign
?: 1);
2742 info
->stroffs
= mod
->core_layout
.size
= info
->symoffs
+ ndst
* sizeof(Elf_Sym
);
2743 mod
->core_layout
.size
+= strtab_size
;
2744 info
->core_typeoffs
= mod
->core_layout
.size
;
2745 mod
->core_layout
.size
+= ndst
* sizeof(char);
2746 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2748 /* Put string table section at end of init part of module. */
2749 strsect
->sh_flags
|= SHF_ALLOC
;
2750 strsect
->sh_entsize
= get_offset(mod
, &mod
->init_layout
.size
, strsect
,
2751 info
->index
.str
) | INIT_OFFSET_MASK
;
2752 pr_debug("\t%s\n", info
->secstrings
+ strsect
->sh_name
);
2754 /* We'll tack temporary mod_kallsyms on the end. */
2755 mod
->init_layout
.size
= ALIGN(mod
->init_layout
.size
,
2756 __alignof__(struct mod_kallsyms
));
2757 info
->mod_kallsyms_init_off
= mod
->init_layout
.size
;
2758 mod
->init_layout
.size
+= sizeof(struct mod_kallsyms
);
2759 info
->init_typeoffs
= mod
->init_layout
.size
;
2760 mod
->init_layout
.size
+= nsrc
* sizeof(char);
2761 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2765 * We use the full symtab and strtab which layout_symtab arranged to
2766 * be appended to the init section. Later we switch to the cut-down
2769 static void add_kallsyms(struct module
*mod
, const struct load_info
*info
)
2771 unsigned int i
, ndst
;
2775 Elf_Shdr
*symsec
= &info
->sechdrs
[info
->index
.sym
];
2777 /* Set up to point into init section. */
2778 mod
->kallsyms
= mod
->init_layout
.base
+ info
->mod_kallsyms_init_off
;
2780 mod
->kallsyms
->symtab
= (void *)symsec
->sh_addr
;
2781 mod
->kallsyms
->num_symtab
= symsec
->sh_size
/ sizeof(Elf_Sym
);
2782 /* Make sure we get permanent strtab: don't use info->strtab. */
2783 mod
->kallsyms
->strtab
= (void *)info
->sechdrs
[info
->index
.str
].sh_addr
;
2784 mod
->kallsyms
->typetab
= mod
->init_layout
.base
+ info
->init_typeoffs
;
2787 * Now populate the cut down core kallsyms for after init
2788 * and set types up while we still have access to sections.
2790 mod
->core_kallsyms
.symtab
= dst
= mod
->core_layout
.base
+ info
->symoffs
;
2791 mod
->core_kallsyms
.strtab
= s
= mod
->core_layout
.base
+ info
->stroffs
;
2792 mod
->core_kallsyms
.typetab
= mod
->core_layout
.base
+ info
->core_typeoffs
;
2793 src
= mod
->kallsyms
->symtab
;
2794 for (ndst
= i
= 0; i
< mod
->kallsyms
->num_symtab
; i
++) {
2795 mod
->kallsyms
->typetab
[i
] = elf_type(src
+ i
, info
);
2796 if (i
== 0 || is_livepatch_module(mod
) ||
2797 is_core_symbol(src
+i
, info
->sechdrs
, info
->hdr
->e_shnum
,
2798 info
->index
.pcpu
)) {
2799 mod
->core_kallsyms
.typetab
[ndst
] =
2800 mod
->kallsyms
->typetab
[i
];
2802 dst
[ndst
++].st_name
= s
- mod
->core_kallsyms
.strtab
;
2803 s
+= strlcpy(s
, &mod
->kallsyms
->strtab
[src
[i
].st_name
],
2807 mod
->core_kallsyms
.num_symtab
= ndst
;
2810 static inline void layout_symtab(struct module
*mod
, struct load_info
*info
)
2814 static void add_kallsyms(struct module
*mod
, const struct load_info
*info
)
2817 #endif /* CONFIG_KALLSYMS */
2819 static void dynamic_debug_setup(struct module
*mod
, struct _ddebug
*debug
, unsigned int num
)
2823 ddebug_add_module(debug
, num
, mod
->name
);
2826 static void dynamic_debug_remove(struct module
*mod
, struct _ddebug
*debug
)
2829 ddebug_remove_module(mod
->name
);
2832 void * __weak
module_alloc(unsigned long size
)
2834 return __vmalloc_node_range(size
, 1, VMALLOC_START
, VMALLOC_END
,
2835 GFP_KERNEL
, PAGE_KERNEL_EXEC
, VM_FLUSH_RESET_PERMS
,
2836 NUMA_NO_NODE
, __builtin_return_address(0));
2839 bool __weak
module_init_section(const char *name
)
2841 return strstarts(name
, ".init");
2844 bool __weak
module_exit_section(const char *name
)
2846 return strstarts(name
, ".exit");
2849 #ifdef CONFIG_DEBUG_KMEMLEAK
2850 static void kmemleak_load_module(const struct module
*mod
,
2851 const struct load_info
*info
)
2855 /* only scan the sections containing data */
2856 kmemleak_scan_area(mod
, sizeof(struct module
), GFP_KERNEL
);
2858 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2859 /* Scan all writable sections that's not executable */
2860 if (!(info
->sechdrs
[i
].sh_flags
& SHF_ALLOC
) ||
2861 !(info
->sechdrs
[i
].sh_flags
& SHF_WRITE
) ||
2862 (info
->sechdrs
[i
].sh_flags
& SHF_EXECINSTR
))
2865 kmemleak_scan_area((void *)info
->sechdrs
[i
].sh_addr
,
2866 info
->sechdrs
[i
].sh_size
, GFP_KERNEL
);
2870 static inline void kmemleak_load_module(const struct module
*mod
,
2871 const struct load_info
*info
)
2876 #ifdef CONFIG_MODULE_SIG
2877 static int module_sig_check(struct load_info
*info
, int flags
)
2880 const unsigned long markerlen
= sizeof(MODULE_SIG_STRING
) - 1;
2882 const void *mod
= info
->hdr
;
2885 * Require flags == 0, as a module with version information
2886 * removed is no longer the module that was signed
2889 info
->len
> markerlen
&&
2890 memcmp(mod
+ info
->len
- markerlen
, MODULE_SIG_STRING
, markerlen
) == 0) {
2891 /* We truncate the module to discard the signature */
2892 info
->len
-= markerlen
;
2893 err
= mod_verify_sig(mod
, info
);
2898 info
->sig_ok
= true;
2901 /* We don't permit modules to be loaded into trusted kernels
2902 * without a valid signature on them, but if we're not
2903 * enforcing, certain errors are non-fatal.
2906 reason
= "Loading of unsigned module";
2909 reason
= "Loading of module with unsupported crypto";
2912 reason
= "Loading of module with unavailable key";
2914 if (is_module_sig_enforced()) {
2915 pr_notice("%s: %s is rejected\n", info
->name
, reason
);
2916 return -EKEYREJECTED
;
2919 return security_locked_down(LOCKDOWN_MODULE_SIGNATURE
);
2921 /* All other errors are fatal, including nomem, unparseable
2922 * signatures and signature check failures - even if signatures
2929 #else /* !CONFIG_MODULE_SIG */
2930 static int module_sig_check(struct load_info
*info
, int flags
)
2934 #endif /* !CONFIG_MODULE_SIG */
2936 /* Sanity checks against invalid binaries, wrong arch, weird elf version. */
2937 static int elf_header_check(struct load_info
*info
)
2939 if (info
->len
< sizeof(*(info
->hdr
)))
2942 if (memcmp(info
->hdr
->e_ident
, ELFMAG
, SELFMAG
) != 0
2943 || info
->hdr
->e_type
!= ET_REL
2944 || !elf_check_arch(info
->hdr
)
2945 || info
->hdr
->e_shentsize
!= sizeof(Elf_Shdr
))
2948 if (info
->hdr
->e_shoff
>= info
->len
2949 || (info
->hdr
->e_shnum
* sizeof(Elf_Shdr
) >
2950 info
->len
- info
->hdr
->e_shoff
))
2956 #define COPY_CHUNK_SIZE (16*PAGE_SIZE)
2958 static int copy_chunked_from_user(void *dst
, const void __user
*usrc
, unsigned long len
)
2961 unsigned long n
= min(len
, COPY_CHUNK_SIZE
);
2963 if (copy_from_user(dst
, usrc
, n
) != 0)
2973 #ifdef CONFIG_LIVEPATCH
2974 static int check_modinfo_livepatch(struct module
*mod
, struct load_info
*info
)
2976 if (get_modinfo(info
, "livepatch")) {
2978 add_taint_module(mod
, TAINT_LIVEPATCH
, LOCKDEP_STILL_OK
);
2979 pr_notice_once("%s: tainting kernel with TAINT_LIVEPATCH\n",
2985 #else /* !CONFIG_LIVEPATCH */
2986 static int check_modinfo_livepatch(struct module
*mod
, struct load_info
*info
)
2988 if (get_modinfo(info
, "livepatch")) {
2989 pr_err("%s: module is marked as livepatch module, but livepatch support is disabled",
2996 #endif /* CONFIG_LIVEPATCH */
2998 static void check_modinfo_retpoline(struct module
*mod
, struct load_info
*info
)
3000 if (retpoline_module_ok(get_modinfo(info
, "retpoline")))
3003 pr_warn("%s: loading module not compiled with retpoline compiler.\n",
3007 /* Sets info->hdr and info->len. */
3008 static int copy_module_from_user(const void __user
*umod
, unsigned long len
,
3009 struct load_info
*info
)
3014 if (info
->len
< sizeof(*(info
->hdr
)))
3017 err
= security_kernel_load_data(LOADING_MODULE
, true);
3021 /* Suck in entire file: we'll want most of it. */
3022 info
->hdr
= __vmalloc(info
->len
, GFP_KERNEL
| __GFP_NOWARN
);
3026 if (copy_chunked_from_user(info
->hdr
, umod
, info
->len
) != 0) {
3031 err
= security_kernel_post_load_data((char *)info
->hdr
, info
->len
,
3032 LOADING_MODULE
, "init_module");
3040 static void free_copy(struct load_info
*info
)
3045 static int rewrite_section_headers(struct load_info
*info
, int flags
)
3049 /* This should always be true, but let's be sure. */
3050 info
->sechdrs
[0].sh_addr
= 0;
3052 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
3053 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
3054 if (shdr
->sh_type
!= SHT_NOBITS
3055 && info
->len
< shdr
->sh_offset
+ shdr
->sh_size
) {
3056 pr_err("Module len %lu truncated\n", info
->len
);
3060 /* Mark all sections sh_addr with their address in the
3062 shdr
->sh_addr
= (size_t)info
->hdr
+ shdr
->sh_offset
;
3064 #ifndef CONFIG_MODULE_UNLOAD
3065 /* Don't load .exit sections */
3066 if (module_exit_section(info
->secstrings
+shdr
->sh_name
))
3067 shdr
->sh_flags
&= ~(unsigned long)SHF_ALLOC
;
3071 /* Track but don't keep modinfo and version sections. */
3072 info
->sechdrs
[info
->index
.vers
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
3073 info
->sechdrs
[info
->index
.info
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
3079 * Set up our basic convenience variables (pointers to section headers,
3080 * search for module section index etc), and do some basic section
3083 * Set info->mod to the temporary copy of the module in info->hdr. The final one
3084 * will be allocated in move_module().
3086 static int setup_load_info(struct load_info
*info
, int flags
)
3090 /* Set up the convenience variables */
3091 info
->sechdrs
= (void *)info
->hdr
+ info
->hdr
->e_shoff
;
3092 info
->secstrings
= (void *)info
->hdr
3093 + info
->sechdrs
[info
->hdr
->e_shstrndx
].sh_offset
;
3095 /* Try to find a name early so we can log errors with a module name */
3096 info
->index
.info
= find_sec(info
, ".modinfo");
3097 if (info
->index
.info
)
3098 info
->name
= get_modinfo(info
, "name");
3100 /* Find internal symbols and strings. */
3101 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
3102 if (info
->sechdrs
[i
].sh_type
== SHT_SYMTAB
) {
3103 info
->index
.sym
= i
;
3104 info
->index
.str
= info
->sechdrs
[i
].sh_link
;
3105 info
->strtab
= (char *)info
->hdr
3106 + info
->sechdrs
[info
->index
.str
].sh_offset
;
3111 if (info
->index
.sym
== 0) {
3112 pr_warn("%s: module has no symbols (stripped?)\n",
3113 info
->name
?: "(missing .modinfo section or name field)");
3117 info
->index
.mod
= find_sec(info
, ".gnu.linkonce.this_module");
3118 if (!info
->index
.mod
) {
3119 pr_warn("%s: No module found in object\n",
3120 info
->name
?: "(missing .modinfo section or name field)");
3123 /* This is temporary: point mod into copy of data. */
3124 info
->mod
= (void *)info
->hdr
+ info
->sechdrs
[info
->index
.mod
].sh_offset
;
3127 * If we didn't load the .modinfo 'name' field earlier, fall back to
3128 * on-disk struct mod 'name' field.
3131 info
->name
= info
->mod
->name
;
3133 if (flags
& MODULE_INIT_IGNORE_MODVERSIONS
)
3134 info
->index
.vers
= 0; /* Pretend no __versions section! */
3136 info
->index
.vers
= find_sec(info
, "__versions");
3138 info
->index
.pcpu
= find_pcpusec(info
);
3143 static int check_modinfo(struct module
*mod
, struct load_info
*info
, int flags
)
3145 const char *modmagic
= get_modinfo(info
, "vermagic");
3148 if (flags
& MODULE_INIT_IGNORE_VERMAGIC
)
3151 /* This is allowed: modprobe --force will invalidate it. */
3153 err
= try_to_force_load(mod
, "bad vermagic");
3156 } else if (!same_magic(modmagic
, vermagic
, info
->index
.vers
)) {
3157 pr_err("%s: version magic '%s' should be '%s'\n",
3158 info
->name
, modmagic
, vermagic
);
3162 if (!get_modinfo(info
, "intree")) {
3163 if (!test_taint(TAINT_OOT_MODULE
))
3164 pr_warn("%s: loading out-of-tree module taints kernel.\n",
3166 add_taint_module(mod
, TAINT_OOT_MODULE
, LOCKDEP_STILL_OK
);
3169 check_modinfo_retpoline(mod
, info
);
3171 if (get_modinfo(info
, "staging")) {
3172 add_taint_module(mod
, TAINT_CRAP
, LOCKDEP_STILL_OK
);
3173 pr_warn("%s: module is from the staging directory, the quality "
3174 "is unknown, you have been warned.\n", mod
->name
);
3177 err
= check_modinfo_livepatch(mod
, info
);
3181 /* Set up license info based on the info section */
3182 set_license(mod
, get_modinfo(info
, "license"));
3187 static int find_module_sections(struct module
*mod
, struct load_info
*info
)
3189 mod
->kp
= section_objs(info
, "__param",
3190 sizeof(*mod
->kp
), &mod
->num_kp
);
3191 mod
->syms
= section_objs(info
, "__ksymtab",
3192 sizeof(*mod
->syms
), &mod
->num_syms
);
3193 mod
->crcs
= section_addr(info
, "__kcrctab");
3194 mod
->gpl_syms
= section_objs(info
, "__ksymtab_gpl",
3195 sizeof(*mod
->gpl_syms
),
3196 &mod
->num_gpl_syms
);
3197 mod
->gpl_crcs
= section_addr(info
, "__kcrctab_gpl");
3198 mod
->gpl_future_syms
= section_objs(info
,
3199 "__ksymtab_gpl_future",
3200 sizeof(*mod
->gpl_future_syms
),
3201 &mod
->num_gpl_future_syms
);
3202 mod
->gpl_future_crcs
= section_addr(info
, "__kcrctab_gpl_future");
3204 #ifdef CONFIG_UNUSED_SYMBOLS
3205 mod
->unused_syms
= section_objs(info
, "__ksymtab_unused",
3206 sizeof(*mod
->unused_syms
),
3207 &mod
->num_unused_syms
);
3208 mod
->unused_crcs
= section_addr(info
, "__kcrctab_unused");
3209 mod
->unused_gpl_syms
= section_objs(info
, "__ksymtab_unused_gpl",
3210 sizeof(*mod
->unused_gpl_syms
),
3211 &mod
->num_unused_gpl_syms
);
3212 mod
->unused_gpl_crcs
= section_addr(info
, "__kcrctab_unused_gpl");
3214 #ifdef CONFIG_CONSTRUCTORS
3215 mod
->ctors
= section_objs(info
, ".ctors",
3216 sizeof(*mod
->ctors
), &mod
->num_ctors
);
3218 mod
->ctors
= section_objs(info
, ".init_array",
3219 sizeof(*mod
->ctors
), &mod
->num_ctors
);
3220 else if (find_sec(info
, ".init_array")) {
3222 * This shouldn't happen with same compiler and binutils
3223 * building all parts of the module.
3225 pr_warn("%s: has both .ctors and .init_array.\n",
3231 mod
->noinstr_text_start
= section_objs(info
, ".noinstr.text", 1,
3232 &mod
->noinstr_text_size
);
3234 #ifdef CONFIG_TRACEPOINTS
3235 mod
->tracepoints_ptrs
= section_objs(info
, "__tracepoints_ptrs",
3236 sizeof(*mod
->tracepoints_ptrs
),
3237 &mod
->num_tracepoints
);
3239 #ifdef CONFIG_TREE_SRCU
3240 mod
->srcu_struct_ptrs
= section_objs(info
, "___srcu_struct_ptrs",
3241 sizeof(*mod
->srcu_struct_ptrs
),
3242 &mod
->num_srcu_structs
);
3244 #ifdef CONFIG_BPF_EVENTS
3245 mod
->bpf_raw_events
= section_objs(info
, "__bpf_raw_tp_map",
3246 sizeof(*mod
->bpf_raw_events
),
3247 &mod
->num_bpf_raw_events
);
3249 #ifdef CONFIG_JUMP_LABEL
3250 mod
->jump_entries
= section_objs(info
, "__jump_table",
3251 sizeof(*mod
->jump_entries
),
3252 &mod
->num_jump_entries
);
3254 #ifdef CONFIG_EVENT_TRACING
3255 mod
->trace_events
= section_objs(info
, "_ftrace_events",
3256 sizeof(*mod
->trace_events
),
3257 &mod
->num_trace_events
);
3258 mod
->trace_evals
= section_objs(info
, "_ftrace_eval_map",
3259 sizeof(*mod
->trace_evals
),
3260 &mod
->num_trace_evals
);
3262 #ifdef CONFIG_TRACING
3263 mod
->trace_bprintk_fmt_start
= section_objs(info
, "__trace_printk_fmt",
3264 sizeof(*mod
->trace_bprintk_fmt_start
),
3265 &mod
->num_trace_bprintk_fmt
);
3267 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
3268 /* sechdrs[0].sh_size is always zero */
3269 mod
->ftrace_callsites
= section_objs(info
, FTRACE_CALLSITE_SECTION
,
3270 sizeof(*mod
->ftrace_callsites
),
3271 &mod
->num_ftrace_callsites
);
3273 #ifdef CONFIG_FUNCTION_ERROR_INJECTION
3274 mod
->ei_funcs
= section_objs(info
, "_error_injection_whitelist",
3275 sizeof(*mod
->ei_funcs
),
3276 &mod
->num_ei_funcs
);
3278 #ifdef CONFIG_KPROBES
3279 mod
->kprobes_text_start
= section_objs(info
, ".kprobes.text", 1,
3280 &mod
->kprobes_text_size
);
3281 mod
->kprobe_blacklist
= section_objs(info
, "_kprobe_blacklist",
3282 sizeof(unsigned long),
3283 &mod
->num_kprobe_blacklist
);
3285 #ifdef CONFIG_HAVE_STATIC_CALL_INLINE
3286 mod
->static_call_sites
= section_objs(info
, ".static_call_sites",
3287 sizeof(*mod
->static_call_sites
),
3288 &mod
->num_static_call_sites
);
3290 mod
->extable
= section_objs(info
, "__ex_table",
3291 sizeof(*mod
->extable
), &mod
->num_exentries
);
3293 if (section_addr(info
, "__obsparm"))
3294 pr_warn("%s: Ignoring obsolete parameters\n", mod
->name
);
3296 info
->debug
= section_objs(info
, "__dyndbg",
3297 sizeof(*info
->debug
), &info
->num_debug
);
3302 static int move_module(struct module
*mod
, struct load_info
*info
)
3307 /* Do the allocs. */
3308 ptr
= module_alloc(mod
->core_layout
.size
);
3310 * The pointer to this block is stored in the module structure
3311 * which is inside the block. Just mark it as not being a
3314 kmemleak_not_leak(ptr
);
3318 memset(ptr
, 0, mod
->core_layout
.size
);
3319 mod
->core_layout
.base
= ptr
;
3321 if (mod
->init_layout
.size
) {
3322 ptr
= module_alloc(mod
->init_layout
.size
);
3324 * The pointer to this block is stored in the module structure
3325 * which is inside the block. This block doesn't need to be
3326 * scanned as it contains data and code that will be freed
3327 * after the module is initialized.
3329 kmemleak_ignore(ptr
);
3331 module_memfree(mod
->core_layout
.base
);
3334 memset(ptr
, 0, mod
->init_layout
.size
);
3335 mod
->init_layout
.base
= ptr
;
3337 mod
->init_layout
.base
= NULL
;
3339 /* Transfer each section which specifies SHF_ALLOC */
3340 pr_debug("final section addresses:\n");
3341 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++) {
3343 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
3345 if (!(shdr
->sh_flags
& SHF_ALLOC
))
3348 if (shdr
->sh_entsize
& INIT_OFFSET_MASK
)
3349 dest
= mod
->init_layout
.base
3350 + (shdr
->sh_entsize
& ~INIT_OFFSET_MASK
);
3352 dest
= mod
->core_layout
.base
+ shdr
->sh_entsize
;
3354 if (shdr
->sh_type
!= SHT_NOBITS
)
3355 memcpy(dest
, (void *)shdr
->sh_addr
, shdr
->sh_size
);
3356 /* Update sh_addr to point to copy in image. */
3357 shdr
->sh_addr
= (unsigned long)dest
;
3358 pr_debug("\t0x%lx %s\n",
3359 (long)shdr
->sh_addr
, info
->secstrings
+ shdr
->sh_name
);
3365 static int check_module_license_and_versions(struct module
*mod
)
3367 int prev_taint
= test_taint(TAINT_PROPRIETARY_MODULE
);
3370 * ndiswrapper is under GPL by itself, but loads proprietary modules.
3371 * Don't use add_taint_module(), as it would prevent ndiswrapper from
3372 * using GPL-only symbols it needs.
3374 if (strcmp(mod
->name
, "ndiswrapper") == 0)
3375 add_taint(TAINT_PROPRIETARY_MODULE
, LOCKDEP_NOW_UNRELIABLE
);
3377 /* driverloader was caught wrongly pretending to be under GPL */
3378 if (strcmp(mod
->name
, "driverloader") == 0)
3379 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
3380 LOCKDEP_NOW_UNRELIABLE
);
3382 /* lve claims to be GPL but upstream won't provide source */
3383 if (strcmp(mod
->name
, "lve") == 0)
3384 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
3385 LOCKDEP_NOW_UNRELIABLE
);
3387 if (!prev_taint
&& test_taint(TAINT_PROPRIETARY_MODULE
))
3388 pr_warn("%s: module license taints kernel.\n", mod
->name
);
3390 #ifdef CONFIG_MODVERSIONS
3391 if ((mod
->num_syms
&& !mod
->crcs
)
3392 || (mod
->num_gpl_syms
&& !mod
->gpl_crcs
)
3393 || (mod
->num_gpl_future_syms
&& !mod
->gpl_future_crcs
)
3394 #ifdef CONFIG_UNUSED_SYMBOLS
3395 || (mod
->num_unused_syms
&& !mod
->unused_crcs
)
3396 || (mod
->num_unused_gpl_syms
&& !mod
->unused_gpl_crcs
)
3399 return try_to_force_load(mod
,
3400 "no versions for exported symbols");
3406 static void flush_module_icache(const struct module
*mod
)
3409 * Flush the instruction cache, since we've played with text.
3410 * Do it before processing of module parameters, so the module
3411 * can provide parameter accessor functions of its own.
3413 if (mod
->init_layout
.base
)
3414 flush_icache_range((unsigned long)mod
->init_layout
.base
,
3415 (unsigned long)mod
->init_layout
.base
3416 + mod
->init_layout
.size
);
3417 flush_icache_range((unsigned long)mod
->core_layout
.base
,
3418 (unsigned long)mod
->core_layout
.base
+ mod
->core_layout
.size
);
3421 int __weak
module_frob_arch_sections(Elf_Ehdr
*hdr
,
3429 /* module_blacklist is a comma-separated list of module names */
3430 static char *module_blacklist
;
3431 static bool blacklisted(const char *module_name
)
3436 if (!module_blacklist
)
3439 for (p
= module_blacklist
; *p
; p
+= len
) {
3440 len
= strcspn(p
, ",");
3441 if (strlen(module_name
) == len
&& !memcmp(module_name
, p
, len
))
3448 core_param(module_blacklist
, module_blacklist
, charp
, 0400);
3450 static struct module
*layout_and_allocate(struct load_info
*info
, int flags
)
3456 err
= check_modinfo(info
->mod
, info
, flags
);
3458 return ERR_PTR(err
);
3460 /* Allow arches to frob section contents and sizes. */
3461 err
= module_frob_arch_sections(info
->hdr
, info
->sechdrs
,
3462 info
->secstrings
, info
->mod
);
3464 return ERR_PTR(err
);
3466 err
= module_enforce_rwx_sections(info
->hdr
, info
->sechdrs
,
3467 info
->secstrings
, info
->mod
);
3469 return ERR_PTR(err
);
3471 /* We will do a special allocation for per-cpu sections later. */
3472 info
->sechdrs
[info
->index
.pcpu
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
3475 * Mark ro_after_init section with SHF_RO_AFTER_INIT so that
3476 * layout_sections() can put it in the right place.
3477 * Note: ro_after_init sections also have SHF_{WRITE,ALLOC} set.
3479 ndx
= find_sec(info
, ".data..ro_after_init");
3481 info
->sechdrs
[ndx
].sh_flags
|= SHF_RO_AFTER_INIT
;
3483 * Mark the __jump_table section as ro_after_init as well: these data
3484 * structures are never modified, with the exception of entries that
3485 * refer to code in the __init section, which are annotated as such
3486 * at module load time.
3488 ndx
= find_sec(info
, "__jump_table");
3490 info
->sechdrs
[ndx
].sh_flags
|= SHF_RO_AFTER_INIT
;
3492 /* Determine total sizes, and put offsets in sh_entsize. For now
3493 this is done generically; there doesn't appear to be any
3494 special cases for the architectures. */
3495 layout_sections(info
->mod
, info
);
3496 layout_symtab(info
->mod
, info
);
3498 /* Allocate and move to the final place */
3499 err
= move_module(info
->mod
, info
);
3501 return ERR_PTR(err
);
3503 /* Module has been copied to its final place now: return it. */
3504 mod
= (void *)info
->sechdrs
[info
->index
.mod
].sh_addr
;
3505 kmemleak_load_module(mod
, info
);
3509 /* mod is no longer valid after this! */
3510 static void module_deallocate(struct module
*mod
, struct load_info
*info
)
3512 percpu_modfree(mod
);
3513 module_arch_freeing_init(mod
);
3514 module_memfree(mod
->init_layout
.base
);
3515 module_memfree(mod
->core_layout
.base
);
3518 int __weak
module_finalize(const Elf_Ehdr
*hdr
,
3519 const Elf_Shdr
*sechdrs
,
3525 static int post_relocation(struct module
*mod
, const struct load_info
*info
)
3527 /* Sort exception table now relocations are done. */
3528 sort_extable(mod
->extable
, mod
->extable
+ mod
->num_exentries
);
3530 /* Copy relocated percpu area over. */
3531 percpu_modcopy(mod
, (void *)info
->sechdrs
[info
->index
.pcpu
].sh_addr
,
3532 info
->sechdrs
[info
->index
.pcpu
].sh_size
);
3534 /* Setup kallsyms-specific fields. */
3535 add_kallsyms(mod
, info
);
3537 /* Arch-specific module finalizing. */
3538 return module_finalize(info
->hdr
, info
->sechdrs
, mod
);
3541 /* Is this module of this name done loading? No locks held. */
3542 static bool finished_loading(const char *name
)
3548 * The module_mutex should not be a heavily contended lock;
3549 * if we get the occasional sleep here, we'll go an extra iteration
3550 * in the wait_event_interruptible(), which is harmless.
3552 sched_annotate_sleep();
3553 mutex_lock(&module_mutex
);
3554 mod
= find_module_all(name
, strlen(name
), true);
3555 ret
= !mod
|| mod
->state
== MODULE_STATE_LIVE
;
3556 mutex_unlock(&module_mutex
);
3561 /* Call module constructors. */
3562 static void do_mod_ctors(struct module
*mod
)
3564 #ifdef CONFIG_CONSTRUCTORS
3567 for (i
= 0; i
< mod
->num_ctors
; i
++)
3572 /* For freeing module_init on success, in case kallsyms traversing */
3573 struct mod_initfree
{
3574 struct llist_node node
;
3578 static void do_free_init(struct work_struct
*w
)
3580 struct llist_node
*pos
, *n
, *list
;
3581 struct mod_initfree
*initfree
;
3583 list
= llist_del_all(&init_free_list
);
3587 llist_for_each_safe(pos
, n
, list
) {
3588 initfree
= container_of(pos
, struct mod_initfree
, node
);
3589 module_memfree(initfree
->module_init
);
3594 static int __init
modules_wq_init(void)
3596 INIT_WORK(&init_free_wq
, do_free_init
);
3597 init_llist_head(&init_free_list
);
3600 module_init(modules_wq_init
);
3603 * This is where the real work happens.
3605 * Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb
3606 * helper command 'lx-symbols'.
3608 static noinline
int do_init_module(struct module
*mod
)
3611 struct mod_initfree
*freeinit
;
3613 freeinit
= kmalloc(sizeof(*freeinit
), GFP_KERNEL
);
3618 freeinit
->module_init
= mod
->init_layout
.base
;
3621 * We want to find out whether @mod uses async during init. Clear
3622 * PF_USED_ASYNC. async_schedule*() will set it.
3624 current
->flags
&= ~PF_USED_ASYNC
;
3627 /* Start the module */
3628 if (mod
->init
!= NULL
)
3629 ret
= do_one_initcall(mod
->init
);
3631 goto fail_free_freeinit
;
3634 pr_warn("%s: '%s'->init suspiciously returned %d, it should "
3635 "follow 0/-E convention\n"
3636 "%s: loading module anyway...\n",
3637 __func__
, mod
->name
, ret
, __func__
);
3641 /* Now it's a first class citizen! */
3642 mod
->state
= MODULE_STATE_LIVE
;
3643 blocking_notifier_call_chain(&module_notify_list
,
3644 MODULE_STATE_LIVE
, mod
);
3647 * We need to finish all async code before the module init sequence
3648 * is done. This has potential to deadlock. For example, a newly
3649 * detected block device can trigger request_module() of the
3650 * default iosched from async probing task. Once userland helper
3651 * reaches here, async_synchronize_full() will wait on the async
3652 * task waiting on request_module() and deadlock.
3654 * This deadlock is avoided by perfomring async_synchronize_full()
3655 * iff module init queued any async jobs. This isn't a full
3656 * solution as it will deadlock the same if module loading from
3657 * async jobs nests more than once; however, due to the various
3658 * constraints, this hack seems to be the best option for now.
3659 * Please refer to the following thread for details.
3661 * http://thread.gmane.org/gmane.linux.kernel/1420814
3663 if (!mod
->async_probe_requested
&& (current
->flags
& PF_USED_ASYNC
))
3664 async_synchronize_full();
3666 ftrace_free_mem(mod
, mod
->init_layout
.base
, mod
->init_layout
.base
+
3667 mod
->init_layout
.size
);
3668 mutex_lock(&module_mutex
);
3669 /* Drop initial reference. */
3671 trim_init_extable(mod
);
3672 #ifdef CONFIG_KALLSYMS
3673 /* Switch to core kallsyms now init is done: kallsyms may be walking! */
3674 rcu_assign_pointer(mod
->kallsyms
, &mod
->core_kallsyms
);
3676 module_enable_ro(mod
, true);
3677 mod_tree_remove_init(mod
);
3678 module_arch_freeing_init(mod
);
3679 mod
->init_layout
.base
= NULL
;
3680 mod
->init_layout
.size
= 0;
3681 mod
->init_layout
.ro_size
= 0;
3682 mod
->init_layout
.ro_after_init_size
= 0;
3683 mod
->init_layout
.text_size
= 0;
3685 * We want to free module_init, but be aware that kallsyms may be
3686 * walking this with preempt disabled. In all the failure paths, we
3687 * call synchronize_rcu(), but we don't want to slow down the success
3688 * path. module_memfree() cannot be called in an interrupt, so do the
3689 * work and call synchronize_rcu() in a work queue.
3691 * Note that module_alloc() on most architectures creates W+X page
3692 * mappings which won't be cleaned up until do_free_init() runs. Any
3693 * code such as mark_rodata_ro() which depends on those mappings to
3694 * be cleaned up needs to sync with the queued work - ie
3697 if (llist_add(&freeinit
->node
, &init_free_list
))
3698 schedule_work(&init_free_wq
);
3700 mutex_unlock(&module_mutex
);
3701 wake_up_all(&module_wq
);
3708 /* Try to protect us from buggy refcounters. */
3709 mod
->state
= MODULE_STATE_GOING
;
3712 blocking_notifier_call_chain(&module_notify_list
,
3713 MODULE_STATE_GOING
, mod
);
3714 klp_module_going(mod
);
3715 ftrace_release_mod(mod
);
3717 wake_up_all(&module_wq
);
3721 static int may_init_module(void)
3723 if (!capable(CAP_SYS_MODULE
) || modules_disabled
)
3730 * We try to place it in the list now to make sure it's unique before
3731 * we dedicate too many resources. In particular, temporary percpu
3732 * memory exhaustion.
3734 static int add_unformed_module(struct module
*mod
)
3739 mod
->state
= MODULE_STATE_UNFORMED
;
3742 mutex_lock(&module_mutex
);
3743 old
= find_module_all(mod
->name
, strlen(mod
->name
), true);
3745 if (old
->state
!= MODULE_STATE_LIVE
) {
3746 /* Wait in case it fails to load. */
3747 mutex_unlock(&module_mutex
);
3748 err
= wait_event_interruptible(module_wq
,
3749 finished_loading(mod
->name
));
3757 mod_update_bounds(mod
);
3758 list_add_rcu(&mod
->list
, &modules
);
3759 mod_tree_insert(mod
);
3763 mutex_unlock(&module_mutex
);
3768 static int complete_formation(struct module
*mod
, struct load_info
*info
)
3772 mutex_lock(&module_mutex
);
3774 /* Find duplicate symbols (must be called under lock). */
3775 err
= verify_exported_symbols(mod
);
3779 /* This relies on module_mutex for list integrity. */
3780 module_bug_finalize(info
->hdr
, info
->sechdrs
, mod
);
3782 module_enable_ro(mod
, false);
3783 module_enable_nx(mod
);
3784 module_enable_x(mod
);
3786 /* Mark state as coming so strong_try_module_get() ignores us,
3787 * but kallsyms etc. can see us. */
3788 mod
->state
= MODULE_STATE_COMING
;
3789 mutex_unlock(&module_mutex
);
3794 mutex_unlock(&module_mutex
);
3798 static int prepare_coming_module(struct module
*mod
)
3802 ftrace_module_enable(mod
);
3803 err
= klp_module_coming(mod
);
3807 err
= blocking_notifier_call_chain_robust(&module_notify_list
,
3808 MODULE_STATE_COMING
, MODULE_STATE_GOING
, mod
);
3809 err
= notifier_to_errno(err
);
3811 klp_module_going(mod
);
3816 static int unknown_module_param_cb(char *param
, char *val
, const char *modname
,
3819 struct module
*mod
= arg
;
3822 if (strcmp(param
, "async_probe") == 0) {
3823 mod
->async_probe_requested
= true;
3827 /* Check for magic 'dyndbg' arg */
3828 ret
= ddebug_dyndbg_module_param_cb(param
, val
, modname
);
3830 pr_warn("%s: unknown parameter '%s' ignored\n", modname
, param
);
3834 /* Allocate and load the module: note that size of section 0 is always
3835 zero, and we rely on this for optional sections. */
3836 static int load_module(struct load_info
*info
, const char __user
*uargs
,
3843 err
= elf_header_check(info
);
3847 err
= setup_load_info(info
, flags
);
3851 if (blacklisted(info
->name
)) {
3856 err
= module_sig_check(info
, flags
);
3860 err
= rewrite_section_headers(info
, flags
);
3864 /* Check module struct version now, before we try to use module. */
3865 if (!check_modstruct_version(info
, info
->mod
)) {
3870 /* Figure out module layout, and allocate all the memory. */
3871 mod
= layout_and_allocate(info
, flags
);
3877 audit_log_kern_module(mod
->name
);
3879 /* Reserve our place in the list. */
3880 err
= add_unformed_module(mod
);
3884 #ifdef CONFIG_MODULE_SIG
3885 mod
->sig_ok
= info
->sig_ok
;
3887 pr_notice_once("%s: module verification failed: signature "
3888 "and/or required key missing - tainting "
3889 "kernel\n", mod
->name
);
3890 add_taint_module(mod
, TAINT_UNSIGNED_MODULE
, LOCKDEP_STILL_OK
);
3894 /* To avoid stressing percpu allocator, do this once we're unique. */
3895 err
= percpu_modalloc(mod
, info
);
3899 /* Now module is in final location, initialize linked lists, etc. */
3900 err
= module_unload_init(mod
);
3904 init_param_lock(mod
);
3906 /* Now we've got everything in the final locations, we can
3907 * find optional sections. */
3908 err
= find_module_sections(mod
, info
);
3912 err
= check_module_license_and_versions(mod
);
3916 /* Set up MODINFO_ATTR fields */
3917 setup_modinfo(mod
, info
);
3919 /* Fix up syms, so that st_value is a pointer to location. */
3920 err
= simplify_symbols(mod
, info
);
3924 err
= apply_relocations(mod
, info
);
3928 err
= post_relocation(mod
, info
);
3932 flush_module_icache(mod
);
3934 /* Now copy in args */
3935 mod
->args
= strndup_user(uargs
, ~0UL >> 1);
3936 if (IS_ERR(mod
->args
)) {
3937 err
= PTR_ERR(mod
->args
);
3938 goto free_arch_cleanup
;
3941 dynamic_debug_setup(mod
, info
->debug
, info
->num_debug
);
3943 /* Ftrace init must be called in the MODULE_STATE_UNFORMED state */
3944 ftrace_module_init(mod
);
3946 /* Finally it's fully formed, ready to start executing. */
3947 err
= complete_formation(mod
, info
);
3949 goto ddebug_cleanup
;
3951 err
= prepare_coming_module(mod
);
3955 /* Module is ready to execute: parsing args may do that. */
3956 after_dashes
= parse_args(mod
->name
, mod
->args
, mod
->kp
, mod
->num_kp
,
3958 unknown_module_param_cb
);
3959 if (IS_ERR(after_dashes
)) {
3960 err
= PTR_ERR(after_dashes
);
3961 goto coming_cleanup
;
3962 } else if (after_dashes
) {
3963 pr_warn("%s: parameters '%s' after `--' ignored\n",
3964 mod
->name
, after_dashes
);
3967 /* Link in to sysfs. */
3968 err
= mod_sysfs_setup(mod
, info
, mod
->kp
, mod
->num_kp
);
3970 goto coming_cleanup
;
3972 if (is_livepatch_module(mod
)) {
3973 err
= copy_module_elf(mod
, info
);
3978 /* Get rid of temporary copy. */
3982 trace_module_load(mod
);
3984 return do_init_module(mod
);
3987 mod_sysfs_teardown(mod
);
3989 mod
->state
= MODULE_STATE_GOING
;
3990 destroy_params(mod
->kp
, mod
->num_kp
);
3991 blocking_notifier_call_chain(&module_notify_list
,
3992 MODULE_STATE_GOING
, mod
);
3993 klp_module_going(mod
);
3995 /* module_bug_cleanup needs module_mutex protection */
3996 mutex_lock(&module_mutex
);
3997 module_bug_cleanup(mod
);
3998 mutex_unlock(&module_mutex
);
4001 ftrace_release_mod(mod
);
4002 dynamic_debug_remove(mod
, info
->debug
);
4006 module_arch_cleanup(mod
);
4010 module_unload_free(mod
);
4012 mutex_lock(&module_mutex
);
4013 /* Unlink carefully: kallsyms could be walking list. */
4014 list_del_rcu(&mod
->list
);
4015 mod_tree_remove(mod
);
4016 wake_up_all(&module_wq
);
4017 /* Wait for RCU-sched synchronizing before releasing mod->list. */
4019 mutex_unlock(&module_mutex
);
4021 /* Free lock-classes; relies on the preceding sync_rcu() */
4022 lockdep_free_key_range(mod
->core_layout
.base
, mod
->core_layout
.size
);
4024 module_deallocate(mod
, info
);
4030 SYSCALL_DEFINE3(init_module
, void __user
*, umod
,
4031 unsigned long, len
, const char __user
*, uargs
)
4034 struct load_info info
= { };
4036 err
= may_init_module();
4040 pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
4043 err
= copy_module_from_user(umod
, len
, &info
);
4047 return load_module(&info
, uargs
, 0);
4050 SYSCALL_DEFINE3(finit_module
, int, fd
, const char __user
*, uargs
, int, flags
)
4052 struct load_info info
= { };
4056 err
= may_init_module();
4060 pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd
, uargs
, flags
);
4062 if (flags
& ~(MODULE_INIT_IGNORE_MODVERSIONS
4063 |MODULE_INIT_IGNORE_VERMAGIC
))
4066 err
= kernel_read_file_from_fd(fd
, 0, &hdr
, INT_MAX
, NULL
,
4073 return load_module(&info
, uargs
, flags
);
4076 static inline int within(unsigned long addr
, void *start
, unsigned long size
)
4078 return ((void *)addr
>= start
&& (void *)addr
< start
+ size
);
4081 #ifdef CONFIG_KALLSYMS
4083 * This ignores the intensely annoying "mapping symbols" found
4084 * in ARM ELF files: $a, $t and $d.
4086 static inline int is_arm_mapping_symbol(const char *str
)
4088 if (str
[0] == '.' && str
[1] == 'L')
4090 return str
[0] == '$' && strchr("axtd", str
[1])
4091 && (str
[2] == '\0' || str
[2] == '.');
4094 static const char *kallsyms_symbol_name(struct mod_kallsyms
*kallsyms
, unsigned int symnum
)
4096 return kallsyms
->strtab
+ kallsyms
->symtab
[symnum
].st_name
;
4100 * Given a module and address, find the corresponding symbol and return its name
4101 * while providing its size and offset if needed.
4103 static const char *find_kallsyms_symbol(struct module
*mod
,
4105 unsigned long *size
,
4106 unsigned long *offset
)
4108 unsigned int i
, best
= 0;
4109 unsigned long nextval
, bestval
;
4110 struct mod_kallsyms
*kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
4112 /* At worse, next value is at end of module */
4113 if (within_module_init(addr
, mod
))
4114 nextval
= (unsigned long)mod
->init_layout
.base
+mod
->init_layout
.text_size
;
4116 nextval
= (unsigned long)mod
->core_layout
.base
+mod
->core_layout
.text_size
;
4118 bestval
= kallsyms_symbol_value(&kallsyms
->symtab
[best
]);
4120 /* Scan for closest preceding symbol, and next symbol. (ELF
4121 starts real symbols at 1). */
4122 for (i
= 1; i
< kallsyms
->num_symtab
; i
++) {
4123 const Elf_Sym
*sym
= &kallsyms
->symtab
[i
];
4124 unsigned long thisval
= kallsyms_symbol_value(sym
);
4126 if (sym
->st_shndx
== SHN_UNDEF
)
4129 /* We ignore unnamed symbols: they're uninformative
4130 * and inserted at a whim. */
4131 if (*kallsyms_symbol_name(kallsyms
, i
) == '\0'
4132 || is_arm_mapping_symbol(kallsyms_symbol_name(kallsyms
, i
)))
4135 if (thisval
<= addr
&& thisval
> bestval
) {
4139 if (thisval
> addr
&& thisval
< nextval
)
4147 *size
= nextval
- bestval
;
4149 *offset
= addr
- bestval
;
4151 return kallsyms_symbol_name(kallsyms
, best
);
4154 void * __weak
dereference_module_function_descriptor(struct module
*mod
,
4160 /* For kallsyms to ask for address resolution. NULL means not found. Careful
4161 * not to lock to avoid deadlock on oopses, simply disable preemption. */
4162 const char *module_address_lookup(unsigned long addr
,
4163 unsigned long *size
,
4164 unsigned long *offset
,
4168 const char *ret
= NULL
;
4172 mod
= __module_address(addr
);
4175 *modname
= mod
->name
;
4177 ret
= find_kallsyms_symbol(mod
, addr
, size
, offset
);
4179 /* Make a copy in here where it's safe */
4181 strncpy(namebuf
, ret
, KSYM_NAME_LEN
- 1);
4189 int lookup_module_symbol_name(unsigned long addr
, char *symname
)
4194 list_for_each_entry_rcu(mod
, &modules
, list
) {
4195 if (mod
->state
== MODULE_STATE_UNFORMED
)
4197 if (within_module(addr
, mod
)) {
4200 sym
= find_kallsyms_symbol(mod
, addr
, NULL
, NULL
);
4204 strlcpy(symname
, sym
, KSYM_NAME_LEN
);
4214 int lookup_module_symbol_attrs(unsigned long addr
, unsigned long *size
,
4215 unsigned long *offset
, char *modname
, char *name
)
4220 list_for_each_entry_rcu(mod
, &modules
, list
) {
4221 if (mod
->state
== MODULE_STATE_UNFORMED
)
4223 if (within_module(addr
, mod
)) {
4226 sym
= find_kallsyms_symbol(mod
, addr
, size
, offset
);
4230 strlcpy(modname
, mod
->name
, MODULE_NAME_LEN
);
4232 strlcpy(name
, sym
, KSYM_NAME_LEN
);
4242 int module_get_kallsym(unsigned int symnum
, unsigned long *value
, char *type
,
4243 char *name
, char *module_name
, int *exported
)
4248 list_for_each_entry_rcu(mod
, &modules
, list
) {
4249 struct mod_kallsyms
*kallsyms
;
4251 if (mod
->state
== MODULE_STATE_UNFORMED
)
4253 kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
4254 if (symnum
< kallsyms
->num_symtab
) {
4255 const Elf_Sym
*sym
= &kallsyms
->symtab
[symnum
];
4257 *value
= kallsyms_symbol_value(sym
);
4258 *type
= kallsyms
->typetab
[symnum
];
4259 strlcpy(name
, kallsyms_symbol_name(kallsyms
, symnum
), KSYM_NAME_LEN
);
4260 strlcpy(module_name
, mod
->name
, MODULE_NAME_LEN
);
4261 *exported
= is_exported(name
, *value
, mod
);
4265 symnum
-= kallsyms
->num_symtab
;
4271 /* Given a module and name of symbol, find and return the symbol's value */
4272 static unsigned long find_kallsyms_symbol_value(struct module
*mod
, const char *name
)
4275 struct mod_kallsyms
*kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
4277 for (i
= 0; i
< kallsyms
->num_symtab
; i
++) {
4278 const Elf_Sym
*sym
= &kallsyms
->symtab
[i
];
4280 if (strcmp(name
, kallsyms_symbol_name(kallsyms
, i
)) == 0 &&
4281 sym
->st_shndx
!= SHN_UNDEF
)
4282 return kallsyms_symbol_value(sym
);
4287 /* Look for this name: can be of form module:name. */
4288 unsigned long module_kallsyms_lookup_name(const char *name
)
4292 unsigned long ret
= 0;
4294 /* Don't lock: we're in enough trouble already. */
4296 if ((colon
= strnchr(name
, MODULE_NAME_LEN
, ':')) != NULL
) {
4297 if ((mod
= find_module_all(name
, colon
- name
, false)) != NULL
)
4298 ret
= find_kallsyms_symbol_value(mod
, colon
+1);
4300 list_for_each_entry_rcu(mod
, &modules
, list
) {
4301 if (mod
->state
== MODULE_STATE_UNFORMED
)
4303 if ((ret
= find_kallsyms_symbol_value(mod
, name
)) != 0)
4311 int module_kallsyms_on_each_symbol(int (*fn
)(void *, const char *,
4312 struct module
*, unsigned long),
4319 module_assert_mutex();
4321 list_for_each_entry(mod
, &modules
, list
) {
4322 /* We hold module_mutex: no need for rcu_dereference_sched */
4323 struct mod_kallsyms
*kallsyms
= mod
->kallsyms
;
4325 if (mod
->state
== MODULE_STATE_UNFORMED
)
4327 for (i
= 0; i
< kallsyms
->num_symtab
; i
++) {
4328 const Elf_Sym
*sym
= &kallsyms
->symtab
[i
];
4330 if (sym
->st_shndx
== SHN_UNDEF
)
4333 ret
= fn(data
, kallsyms_symbol_name(kallsyms
, i
),
4334 mod
, kallsyms_symbol_value(sym
));
4341 #endif /* CONFIG_KALLSYMS */
4343 /* Maximum number of characters written by module_flags() */
4344 #define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4)
4346 /* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */
4347 static char *module_flags(struct module
*mod
, char *buf
)
4351 BUG_ON(mod
->state
== MODULE_STATE_UNFORMED
);
4353 mod
->state
== MODULE_STATE_GOING
||
4354 mod
->state
== MODULE_STATE_COMING
) {
4356 bx
+= module_flags_taint(mod
, buf
+ bx
);
4357 /* Show a - for module-is-being-unloaded */
4358 if (mod
->state
== MODULE_STATE_GOING
)
4360 /* Show a + for module-is-being-loaded */
4361 if (mod
->state
== MODULE_STATE_COMING
)
4370 #ifdef CONFIG_PROC_FS
4371 /* Called by the /proc file system to return a list of modules. */
4372 static void *m_start(struct seq_file
*m
, loff_t
*pos
)
4374 mutex_lock(&module_mutex
);
4375 return seq_list_start(&modules
, *pos
);
4378 static void *m_next(struct seq_file
*m
, void *p
, loff_t
*pos
)
4380 return seq_list_next(p
, &modules
, pos
);
4383 static void m_stop(struct seq_file
*m
, void *p
)
4385 mutex_unlock(&module_mutex
);
4388 static int m_show(struct seq_file
*m
, void *p
)
4390 struct module
*mod
= list_entry(p
, struct module
, list
);
4391 char buf
[MODULE_FLAGS_BUF_SIZE
];
4394 /* We always ignore unformed modules. */
4395 if (mod
->state
== MODULE_STATE_UNFORMED
)
4398 seq_printf(m
, "%s %u",
4399 mod
->name
, mod
->init_layout
.size
+ mod
->core_layout
.size
);
4400 print_unload_info(m
, mod
);
4402 /* Informative for users. */
4403 seq_printf(m
, " %s",
4404 mod
->state
== MODULE_STATE_GOING
? "Unloading" :
4405 mod
->state
== MODULE_STATE_COMING
? "Loading" :
4407 /* Used by oprofile and other similar tools. */
4408 value
= m
->private ? NULL
: mod
->core_layout
.base
;
4409 seq_printf(m
, " 0x%px", value
);
4413 seq_printf(m
, " %s", module_flags(mod
, buf
));
4419 /* Format: modulename size refcount deps address
4421 Where refcount is a number or -, and deps is a comma-separated list
4424 static const struct seq_operations modules_op
= {
4432 * This also sets the "private" pointer to non-NULL if the
4433 * kernel pointers should be hidden (so you can just test
4434 * "m->private" to see if you should keep the values private).
4436 * We use the same logic as for /proc/kallsyms.
4438 static int modules_open(struct inode
*inode
, struct file
*file
)
4440 int err
= seq_open(file
, &modules_op
);
4443 struct seq_file
*m
= file
->private_data
;
4444 m
->private = kallsyms_show_value(file
->f_cred
) ? NULL
: (void *)8ul;
4450 static const struct proc_ops modules_proc_ops
= {
4451 .proc_flags
= PROC_ENTRY_PERMANENT
,
4452 .proc_open
= modules_open
,
4453 .proc_read
= seq_read
,
4454 .proc_lseek
= seq_lseek
,
4455 .proc_release
= seq_release
,
4458 static int __init
proc_modules_init(void)
4460 proc_create("modules", 0, NULL
, &modules_proc_ops
);
4463 module_init(proc_modules_init
);
4466 /* Given an address, look for it in the module exception tables. */
4467 const struct exception_table_entry
*search_module_extables(unsigned long addr
)
4469 const struct exception_table_entry
*e
= NULL
;
4473 mod
= __module_address(addr
);
4477 if (!mod
->num_exentries
)
4480 e
= search_extable(mod
->extable
,
4487 * Now, if we found one, we are running inside it now, hence
4488 * we cannot unload the module, hence no refcnt needed.
4494 * is_module_address - is this address inside a module?
4495 * @addr: the address to check.
4497 * See is_module_text_address() if you simply want to see if the address
4498 * is code (not data).
4500 bool is_module_address(unsigned long addr
)
4505 ret
= __module_address(addr
) != NULL
;
4512 * __module_address - get the module which contains an address.
4513 * @addr: the address.
4515 * Must be called with preempt disabled or module mutex held so that
4516 * module doesn't get freed during this.
4518 struct module
*__module_address(unsigned long addr
)
4522 if (addr
< module_addr_min
|| addr
> module_addr_max
)
4525 module_assert_mutex_or_preempt();
4527 mod
= mod_find(addr
);
4529 BUG_ON(!within_module(addr
, mod
));
4530 if (mod
->state
== MODULE_STATE_UNFORMED
)
4537 * is_module_text_address - is this address inside module code?
4538 * @addr: the address to check.
4540 * See is_module_address() if you simply want to see if the address is
4541 * anywhere in a module. See kernel_text_address() for testing if an
4542 * address corresponds to kernel or module code.
4544 bool is_module_text_address(unsigned long addr
)
4549 ret
= __module_text_address(addr
) != NULL
;
4556 * __module_text_address - get the module whose code contains an address.
4557 * @addr: the address.
4559 * Must be called with preempt disabled or module mutex held so that
4560 * module doesn't get freed during this.
4562 struct module
*__module_text_address(unsigned long addr
)
4564 struct module
*mod
= __module_address(addr
);
4566 /* Make sure it's within the text section. */
4567 if (!within(addr
, mod
->init_layout
.base
, mod
->init_layout
.text_size
)
4568 && !within(addr
, mod
->core_layout
.base
, mod
->core_layout
.text_size
))
4574 /* Don't grab lock, we're oopsing. */
4575 void print_modules(void)
4578 char buf
[MODULE_FLAGS_BUF_SIZE
];
4580 printk(KERN_DEFAULT
"Modules linked in:");
4581 /* Most callers should already have preempt disabled, but make sure */
4583 list_for_each_entry_rcu(mod
, &modules
, list
) {
4584 if (mod
->state
== MODULE_STATE_UNFORMED
)
4586 pr_cont(" %s%s", mod
->name
, module_flags(mod
, buf
));
4589 if (last_unloaded_module
[0])
4590 pr_cont(" [last unloaded: %s]", last_unloaded_module
);
4594 #ifdef CONFIG_MODVERSIONS
4595 /* Generate the signature for all relevant module structures here.
4596 * If these change, we don't want to try to parse the module. */
4597 void module_layout(struct module
*mod
,
4598 struct modversion_info
*ver
,
4599 struct kernel_param
*kp
,
4600 struct kernel_symbol
*ks
,
4601 struct tracepoint
* const *tp
)
4604 EXPORT_SYMBOL(module_layout
);