2 Copyright (C) 2002 Richard Henderson
3 Copyright (C) 2001 Rusty Russell, 2002, 2010 Rusty Russell IBM.
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 #include <linux/export.h>
20 #include <linux/extable.h>
21 #include <linux/moduleloader.h>
22 #include <linux/trace_events.h>
23 #include <linux/init.h>
24 #include <linux/kallsyms.h>
25 #include <linux/file.h>
27 #include <linux/sysfs.h>
28 #include <linux/kernel.h>
29 #include <linux/slab.h>
30 #include <linux/vmalloc.h>
31 #include <linux/elf.h>
32 #include <linux/proc_fs.h>
33 #include <linux/security.h>
34 #include <linux/seq_file.h>
35 #include <linux/syscalls.h>
36 #include <linux/fcntl.h>
37 #include <linux/rcupdate.h>
38 #include <linux/capability.h>
39 #include <linux/cpu.h>
40 #include <linux/moduleparam.h>
41 #include <linux/errno.h>
42 #include <linux/err.h>
43 #include <linux/vermagic.h>
44 #include <linux/notifier.h>
45 #include <linux/sched.h>
46 #include <linux/device.h>
47 #include <linux/string.h>
48 #include <linux/mutex.h>
49 #include <linux/rculist.h>
50 #include <linux/uaccess.h>
51 #include <asm/cacheflush.h>
52 #include <asm/mmu_context.h>
53 #include <linux/license.h>
54 #include <asm/sections.h>
55 #include <linux/tracepoint.h>
56 #include <linux/ftrace.h>
57 #include <linux/livepatch.h>
58 #include <linux/async.h>
59 #include <linux/percpu.h>
60 #include <linux/kmemleak.h>
61 #include <linux/jump_label.h>
62 #include <linux/pfn.h>
63 #include <linux/bsearch.h>
64 #include <linux/dynamic_debug.h>
65 #include <linux/audit.h>
66 #include <uapi/linux/module.h>
67 #include "module-internal.h"
69 #define CREATE_TRACE_POINTS
70 #include <trace/events/module.h>
72 #ifndef ARCH_SHF_SMALL
73 #define ARCH_SHF_SMALL 0
77 * Modules' sections will be aligned on page boundaries
78 * to ensure complete separation of code and data, but
79 * only when CONFIG_STRICT_MODULE_RWX=y
81 #ifdef CONFIG_STRICT_MODULE_RWX
82 # define debug_align(X) ALIGN(X, PAGE_SIZE)
84 # define debug_align(X) (X)
87 /* If this is set, the section belongs in the init part of the module */
88 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
92 * 1) List of modules (also safely readable with preempt_disable),
93 * 2) module_use links,
94 * 3) module_addr_min/module_addr_max.
95 * (delete and add uses RCU list operations). */
96 DEFINE_MUTEX(module_mutex
);
97 EXPORT_SYMBOL_GPL(module_mutex
);
98 static LIST_HEAD(modules
);
100 #ifdef CONFIG_MODULES_TREE_LOOKUP
103 * Use a latched RB-tree for __module_address(); this allows us to use
104 * RCU-sched lookups of the address from any context.
106 * This is conditional on PERF_EVENTS || TRACING because those can really hit
107 * __module_address() hard by doing a lot of stack unwinding; potentially from
111 static __always_inline
unsigned long __mod_tree_val(struct latch_tree_node
*n
)
113 struct module_layout
*layout
= container_of(n
, struct module_layout
, mtn
.node
);
115 return (unsigned long)layout
->base
;
118 static __always_inline
unsigned long __mod_tree_size(struct latch_tree_node
*n
)
120 struct module_layout
*layout
= container_of(n
, struct module_layout
, mtn
.node
);
122 return (unsigned long)layout
->size
;
125 static __always_inline
bool
126 mod_tree_less(struct latch_tree_node
*a
, struct latch_tree_node
*b
)
128 return __mod_tree_val(a
) < __mod_tree_val(b
);
131 static __always_inline
int
132 mod_tree_comp(void *key
, struct latch_tree_node
*n
)
134 unsigned long val
= (unsigned long)key
;
135 unsigned long start
, end
;
137 start
= __mod_tree_val(n
);
141 end
= start
+ __mod_tree_size(n
);
148 static const struct latch_tree_ops mod_tree_ops
= {
149 .less
= mod_tree_less
,
150 .comp
= mod_tree_comp
,
153 static struct mod_tree_root
{
154 struct latch_tree_root root
;
155 unsigned long addr_min
;
156 unsigned long addr_max
;
157 } mod_tree __cacheline_aligned
= {
161 #define module_addr_min mod_tree.addr_min
162 #define module_addr_max mod_tree.addr_max
164 static noinline
void __mod_tree_insert(struct mod_tree_node
*node
)
166 latch_tree_insert(&node
->node
, &mod_tree
.root
, &mod_tree_ops
);
169 static void __mod_tree_remove(struct mod_tree_node
*node
)
171 latch_tree_erase(&node
->node
, &mod_tree
.root
, &mod_tree_ops
);
175 * These modifications: insert, remove_init and remove; are serialized by the
178 static void mod_tree_insert(struct module
*mod
)
180 mod
->core_layout
.mtn
.mod
= mod
;
181 mod
->init_layout
.mtn
.mod
= mod
;
183 __mod_tree_insert(&mod
->core_layout
.mtn
);
184 if (mod
->init_layout
.size
)
185 __mod_tree_insert(&mod
->init_layout
.mtn
);
188 static void mod_tree_remove_init(struct module
*mod
)
190 if (mod
->init_layout
.size
)
191 __mod_tree_remove(&mod
->init_layout
.mtn
);
194 static void mod_tree_remove(struct module
*mod
)
196 __mod_tree_remove(&mod
->core_layout
.mtn
);
197 mod_tree_remove_init(mod
);
200 static struct module
*mod_find(unsigned long addr
)
202 struct latch_tree_node
*ltn
;
204 ltn
= latch_tree_find((void *)addr
, &mod_tree
.root
, &mod_tree_ops
);
208 return container_of(ltn
, struct mod_tree_node
, node
)->mod
;
211 #else /* MODULES_TREE_LOOKUP */
213 static unsigned long module_addr_min
= -1UL, module_addr_max
= 0;
215 static void mod_tree_insert(struct module
*mod
) { }
216 static void mod_tree_remove_init(struct module
*mod
) { }
217 static void mod_tree_remove(struct module
*mod
) { }
219 static struct module
*mod_find(unsigned long addr
)
223 list_for_each_entry_rcu(mod
, &modules
, list
) {
224 if (within_module(addr
, mod
))
231 #endif /* MODULES_TREE_LOOKUP */
234 * Bounds of module text, for speeding up __module_address.
235 * Protected by module_mutex.
237 static void __mod_update_bounds(void *base
, unsigned int size
)
239 unsigned long min
= (unsigned long)base
;
240 unsigned long max
= min
+ size
;
242 if (min
< module_addr_min
)
243 module_addr_min
= min
;
244 if (max
> module_addr_max
)
245 module_addr_max
= max
;
248 static void mod_update_bounds(struct module
*mod
)
250 __mod_update_bounds(mod
->core_layout
.base
, mod
->core_layout
.size
);
251 if (mod
->init_layout
.size
)
252 __mod_update_bounds(mod
->init_layout
.base
, mod
->init_layout
.size
);
255 #ifdef CONFIG_KGDB_KDB
256 struct list_head
*kdb_modules
= &modules
; /* kdb needs the list of modules */
257 #endif /* CONFIG_KGDB_KDB */
259 static void module_assert_mutex(void)
261 lockdep_assert_held(&module_mutex
);
264 static void module_assert_mutex_or_preempt(void)
266 #ifdef CONFIG_LOCKDEP
267 if (unlikely(!debug_locks
))
270 WARN_ON_ONCE(!rcu_read_lock_sched_held() &&
271 !lockdep_is_held(&module_mutex
));
275 static bool sig_enforce
= IS_ENABLED(CONFIG_MODULE_SIG_FORCE
);
276 #ifndef CONFIG_MODULE_SIG_FORCE
277 module_param(sig_enforce
, bool_enable_only
, 0644);
278 #endif /* !CONFIG_MODULE_SIG_FORCE */
280 /* Block module loading/unloading? */
281 int modules_disabled
= 0;
282 core_param(nomodule
, modules_disabled
, bint
, 0);
284 /* Waiting for a module to finish initializing? */
285 static DECLARE_WAIT_QUEUE_HEAD(module_wq
);
287 static BLOCKING_NOTIFIER_HEAD(module_notify_list
);
289 int register_module_notifier(struct notifier_block
*nb
)
291 return blocking_notifier_chain_register(&module_notify_list
, nb
);
293 EXPORT_SYMBOL(register_module_notifier
);
295 int unregister_module_notifier(struct notifier_block
*nb
)
297 return blocking_notifier_chain_unregister(&module_notify_list
, nb
);
299 EXPORT_SYMBOL(unregister_module_notifier
);
305 char *secstrings
, *strtab
;
306 unsigned long symoffs
, stroffs
;
307 struct _ddebug
*debug
;
308 unsigned int num_debug
;
310 #ifdef CONFIG_KALLSYMS
311 unsigned long mod_kallsyms_init_off
;
314 unsigned int sym
, str
, mod
, vers
, info
, pcpu
;
319 * We require a truly strong try_module_get(): 0 means success.
320 * Otherwise an error is returned due to ongoing or failed
321 * initialization etc.
323 static inline int strong_try_module_get(struct module
*mod
)
325 BUG_ON(mod
&& mod
->state
== MODULE_STATE_UNFORMED
);
326 if (mod
&& mod
->state
== MODULE_STATE_COMING
)
328 if (try_module_get(mod
))
334 static inline void add_taint_module(struct module
*mod
, unsigned flag
,
335 enum lockdep_ok lockdep_ok
)
337 add_taint(flag
, lockdep_ok
);
338 set_bit(flag
, &mod
->taints
);
342 * A thread that wants to hold a reference to a module only while it
343 * is running can call this to safely exit. nfsd and lockd use this.
345 void __noreturn
__module_put_and_exit(struct module
*mod
, long code
)
350 EXPORT_SYMBOL(__module_put_and_exit
);
352 /* Find a module section: 0 means not found. */
353 static unsigned int find_sec(const struct load_info
*info
, const char *name
)
357 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
358 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
359 /* Alloc bit cleared means "ignore it." */
360 if ((shdr
->sh_flags
& SHF_ALLOC
)
361 && strcmp(info
->secstrings
+ shdr
->sh_name
, name
) == 0)
367 /* Find a module section, or NULL. */
368 static void *section_addr(const struct load_info
*info
, const char *name
)
370 /* Section 0 has sh_addr 0. */
371 return (void *)info
->sechdrs
[find_sec(info
, name
)].sh_addr
;
374 /* Find a module section, or NULL. Fill in number of "objects" in section. */
375 static void *section_objs(const struct load_info
*info
,
380 unsigned int sec
= find_sec(info
, name
);
382 /* Section 0 has sh_addr 0 and sh_size 0. */
383 *num
= info
->sechdrs
[sec
].sh_size
/ object_size
;
384 return (void *)info
->sechdrs
[sec
].sh_addr
;
387 /* Provided by the linker */
388 extern const struct kernel_symbol __start___ksymtab
[];
389 extern const struct kernel_symbol __stop___ksymtab
[];
390 extern const struct kernel_symbol __start___ksymtab_gpl
[];
391 extern const struct kernel_symbol __stop___ksymtab_gpl
[];
392 extern const struct kernel_symbol __start___ksymtab_gpl_future
[];
393 extern const struct kernel_symbol __stop___ksymtab_gpl_future
[];
394 extern const s32 __start___kcrctab
[];
395 extern const s32 __start___kcrctab_gpl
[];
396 extern const s32 __start___kcrctab_gpl_future
[];
397 #ifdef CONFIG_UNUSED_SYMBOLS
398 extern const struct kernel_symbol __start___ksymtab_unused
[];
399 extern const struct kernel_symbol __stop___ksymtab_unused
[];
400 extern const struct kernel_symbol __start___ksymtab_unused_gpl
[];
401 extern const struct kernel_symbol __stop___ksymtab_unused_gpl
[];
402 extern const s32 __start___kcrctab_unused
[];
403 extern const s32 __start___kcrctab_unused_gpl
[];
406 #ifndef CONFIG_MODVERSIONS
407 #define symversion(base, idx) NULL
409 #define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
412 static bool each_symbol_in_section(const struct symsearch
*arr
,
413 unsigned int arrsize
,
414 struct module
*owner
,
415 bool (*fn
)(const struct symsearch
*syms
,
416 struct module
*owner
,
422 for (j
= 0; j
< arrsize
; j
++) {
423 if (fn(&arr
[j
], owner
, data
))
430 /* Returns true as soon as fn returns true, otherwise false. */
431 bool each_symbol_section(bool (*fn
)(const struct symsearch
*arr
,
432 struct module
*owner
,
437 static const struct symsearch arr
[] = {
438 { __start___ksymtab
, __stop___ksymtab
, __start___kcrctab
,
439 NOT_GPL_ONLY
, false },
440 { __start___ksymtab_gpl
, __stop___ksymtab_gpl
,
441 __start___kcrctab_gpl
,
443 { __start___ksymtab_gpl_future
, __stop___ksymtab_gpl_future
,
444 __start___kcrctab_gpl_future
,
445 WILL_BE_GPL_ONLY
, false },
446 #ifdef CONFIG_UNUSED_SYMBOLS
447 { __start___ksymtab_unused
, __stop___ksymtab_unused
,
448 __start___kcrctab_unused
,
449 NOT_GPL_ONLY
, true },
450 { __start___ksymtab_unused_gpl
, __stop___ksymtab_unused_gpl
,
451 __start___kcrctab_unused_gpl
,
456 module_assert_mutex_or_preempt();
458 if (each_symbol_in_section(arr
, ARRAY_SIZE(arr
), NULL
, fn
, data
))
461 list_for_each_entry_rcu(mod
, &modules
, list
) {
462 struct symsearch arr
[] = {
463 { mod
->syms
, mod
->syms
+ mod
->num_syms
, mod
->crcs
,
464 NOT_GPL_ONLY
, false },
465 { mod
->gpl_syms
, mod
->gpl_syms
+ mod
->num_gpl_syms
,
468 { mod
->gpl_future_syms
,
469 mod
->gpl_future_syms
+ mod
->num_gpl_future_syms
,
470 mod
->gpl_future_crcs
,
471 WILL_BE_GPL_ONLY
, false },
472 #ifdef CONFIG_UNUSED_SYMBOLS
474 mod
->unused_syms
+ mod
->num_unused_syms
,
476 NOT_GPL_ONLY
, true },
477 { mod
->unused_gpl_syms
,
478 mod
->unused_gpl_syms
+ mod
->num_unused_gpl_syms
,
479 mod
->unused_gpl_crcs
,
484 if (mod
->state
== MODULE_STATE_UNFORMED
)
487 if (each_symbol_in_section(arr
, ARRAY_SIZE(arr
), mod
, fn
, data
))
492 EXPORT_SYMBOL_GPL(each_symbol_section
);
494 struct find_symbol_arg
{
501 struct module
*owner
;
503 const struct kernel_symbol
*sym
;
506 static bool check_symbol(const struct symsearch
*syms
,
507 struct module
*owner
,
508 unsigned int symnum
, void *data
)
510 struct find_symbol_arg
*fsa
= data
;
513 if (syms
->licence
== GPL_ONLY
)
515 if (syms
->licence
== WILL_BE_GPL_ONLY
&& fsa
->warn
) {
516 pr_warn("Symbol %s is being used by a non-GPL module, "
517 "which will not be allowed in the future\n",
522 #ifdef CONFIG_UNUSED_SYMBOLS
523 if (syms
->unused
&& fsa
->warn
) {
524 pr_warn("Symbol %s is marked as UNUSED, however this module is "
525 "using it.\n", fsa
->name
);
526 pr_warn("This symbol will go away in the future.\n");
527 pr_warn("Please evaluate if this is the right api to use and "
528 "if it really is, submit a report to the linux kernel "
529 "mailing list together with submitting your code for "
535 fsa
->crc
= symversion(syms
->crcs
, symnum
);
536 fsa
->sym
= &syms
->start
[symnum
];
540 static int cmp_name(const void *va
, const void *vb
)
543 const struct kernel_symbol
*b
;
545 return strcmp(a
, b
->name
);
548 static bool find_symbol_in_section(const struct symsearch
*syms
,
549 struct module
*owner
,
552 struct find_symbol_arg
*fsa
= data
;
553 struct kernel_symbol
*sym
;
555 sym
= bsearch(fsa
->name
, syms
->start
, syms
->stop
- syms
->start
,
556 sizeof(struct kernel_symbol
), cmp_name
);
558 if (sym
!= NULL
&& check_symbol(syms
, owner
, sym
- syms
->start
, data
))
564 /* Find a symbol and return it, along with, (optional) crc and
565 * (optional) module which owns it. Needs preempt disabled or module_mutex. */
566 const struct kernel_symbol
*find_symbol(const char *name
,
567 struct module
**owner
,
572 struct find_symbol_arg fsa
;
578 if (each_symbol_section(find_symbol_in_section
, &fsa
)) {
586 pr_debug("Failed to find symbol %s\n", name
);
589 EXPORT_SYMBOL_GPL(find_symbol
);
592 * Search for module by name: must hold module_mutex (or preempt disabled
593 * for read-only access).
595 static struct module
*find_module_all(const char *name
, size_t len
,
600 module_assert_mutex_or_preempt();
602 list_for_each_entry(mod
, &modules
, list
) {
603 if (!even_unformed
&& mod
->state
== MODULE_STATE_UNFORMED
)
605 if (strlen(mod
->name
) == len
&& !memcmp(mod
->name
, name
, len
))
611 struct module
*find_module(const char *name
)
613 module_assert_mutex();
614 return find_module_all(name
, strlen(name
), false);
616 EXPORT_SYMBOL_GPL(find_module
);
620 static inline void __percpu
*mod_percpu(struct module
*mod
)
625 static int percpu_modalloc(struct module
*mod
, struct load_info
*info
)
627 Elf_Shdr
*pcpusec
= &info
->sechdrs
[info
->index
.pcpu
];
628 unsigned long align
= pcpusec
->sh_addralign
;
630 if (!pcpusec
->sh_size
)
633 if (align
> PAGE_SIZE
) {
634 pr_warn("%s: per-cpu alignment %li > %li\n",
635 mod
->name
, align
, PAGE_SIZE
);
639 mod
->percpu
= __alloc_reserved_percpu(pcpusec
->sh_size
, align
);
641 pr_warn("%s: Could not allocate %lu bytes percpu data\n",
642 mod
->name
, (unsigned long)pcpusec
->sh_size
);
645 mod
->percpu_size
= pcpusec
->sh_size
;
649 static void percpu_modfree(struct module
*mod
)
651 free_percpu(mod
->percpu
);
654 static unsigned int find_pcpusec(struct load_info
*info
)
656 return find_sec(info
, ".data..percpu");
659 static void percpu_modcopy(struct module
*mod
,
660 const void *from
, unsigned long size
)
664 for_each_possible_cpu(cpu
)
665 memcpy(per_cpu_ptr(mod
->percpu
, cpu
), from
, size
);
668 bool __is_module_percpu_address(unsigned long addr
, unsigned long *can_addr
)
675 list_for_each_entry_rcu(mod
, &modules
, list
) {
676 if (mod
->state
== MODULE_STATE_UNFORMED
)
678 if (!mod
->percpu_size
)
680 for_each_possible_cpu(cpu
) {
681 void *start
= per_cpu_ptr(mod
->percpu
, cpu
);
682 void *va
= (void *)addr
;
684 if (va
>= start
&& va
< start
+ mod
->percpu_size
) {
686 *can_addr
= (unsigned long) (va
- start
);
687 *can_addr
+= (unsigned long)
688 per_cpu_ptr(mod
->percpu
,
702 * is_module_percpu_address - test whether address is from module static percpu
703 * @addr: address to test
705 * Test whether @addr belongs to module static percpu area.
708 * %true if @addr is from module static percpu area
710 bool is_module_percpu_address(unsigned long addr
)
712 return __is_module_percpu_address(addr
, NULL
);
715 #else /* ... !CONFIG_SMP */
717 static inline void __percpu
*mod_percpu(struct module
*mod
)
721 static int percpu_modalloc(struct module
*mod
, struct load_info
*info
)
723 /* UP modules shouldn't have this section: ENOMEM isn't quite right */
724 if (info
->sechdrs
[info
->index
.pcpu
].sh_size
!= 0)
728 static inline void percpu_modfree(struct module
*mod
)
731 static unsigned int find_pcpusec(struct load_info
*info
)
735 static inline void percpu_modcopy(struct module
*mod
,
736 const void *from
, unsigned long size
)
738 /* pcpusec should be 0, and size of that section should be 0. */
741 bool is_module_percpu_address(unsigned long addr
)
746 bool __is_module_percpu_address(unsigned long addr
, unsigned long *can_addr
)
751 #endif /* CONFIG_SMP */
753 #define MODINFO_ATTR(field) \
754 static void setup_modinfo_##field(struct module *mod, const char *s) \
756 mod->field = kstrdup(s, GFP_KERNEL); \
758 static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
759 struct module_kobject *mk, char *buffer) \
761 return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \
763 static int modinfo_##field##_exists(struct module *mod) \
765 return mod->field != NULL; \
767 static void free_modinfo_##field(struct module *mod) \
772 static struct module_attribute modinfo_##field = { \
773 .attr = { .name = __stringify(field), .mode = 0444 }, \
774 .show = show_modinfo_##field, \
775 .setup = setup_modinfo_##field, \
776 .test = modinfo_##field##_exists, \
777 .free = free_modinfo_##field, \
780 MODINFO_ATTR(version
);
781 MODINFO_ATTR(srcversion
);
783 static char last_unloaded_module
[MODULE_NAME_LEN
+1];
785 #ifdef CONFIG_MODULE_UNLOAD
787 EXPORT_TRACEPOINT_SYMBOL(module_get
);
789 /* MODULE_REF_BASE is the base reference count by kmodule loader. */
790 #define MODULE_REF_BASE 1
792 /* Init the unload section of the module. */
793 static int module_unload_init(struct module
*mod
)
796 * Initialize reference counter to MODULE_REF_BASE.
797 * refcnt == 0 means module is going.
799 atomic_set(&mod
->refcnt
, MODULE_REF_BASE
);
801 INIT_LIST_HEAD(&mod
->source_list
);
802 INIT_LIST_HEAD(&mod
->target_list
);
804 /* Hold reference count during initialization. */
805 atomic_inc(&mod
->refcnt
);
810 /* Does a already use b? */
811 static int already_uses(struct module
*a
, struct module
*b
)
813 struct module_use
*use
;
815 list_for_each_entry(use
, &b
->source_list
, source_list
) {
816 if (use
->source
== a
) {
817 pr_debug("%s uses %s!\n", a
->name
, b
->name
);
821 pr_debug("%s does not use %s!\n", a
->name
, b
->name
);
827 * - we add 'a' as a "source", 'b' as a "target" of module use
828 * - the module_use is added to the list of 'b' sources (so
829 * 'b' can walk the list to see who sourced them), and of 'a'
830 * targets (so 'a' can see what modules it targets).
832 static int add_module_usage(struct module
*a
, struct module
*b
)
834 struct module_use
*use
;
836 pr_debug("Allocating new usage for %s.\n", a
->name
);
837 use
= kmalloc(sizeof(*use
), GFP_ATOMIC
);
839 pr_warn("%s: out of memory loading\n", a
->name
);
845 list_add(&use
->source_list
, &b
->source_list
);
846 list_add(&use
->target_list
, &a
->target_list
);
850 /* Module a uses b: caller needs module_mutex() */
851 int ref_module(struct module
*a
, struct module
*b
)
855 if (b
== NULL
|| already_uses(a
, b
))
858 /* If module isn't available, we fail. */
859 err
= strong_try_module_get(b
);
863 err
= add_module_usage(a
, b
);
870 EXPORT_SYMBOL_GPL(ref_module
);
872 /* Clear the unload stuff of the module. */
873 static void module_unload_free(struct module
*mod
)
875 struct module_use
*use
, *tmp
;
877 mutex_lock(&module_mutex
);
878 list_for_each_entry_safe(use
, tmp
, &mod
->target_list
, target_list
) {
879 struct module
*i
= use
->target
;
880 pr_debug("%s unusing %s\n", mod
->name
, i
->name
);
882 list_del(&use
->source_list
);
883 list_del(&use
->target_list
);
886 mutex_unlock(&module_mutex
);
889 #ifdef CONFIG_MODULE_FORCE_UNLOAD
890 static inline int try_force_unload(unsigned int flags
)
892 int ret
= (flags
& O_TRUNC
);
894 add_taint(TAINT_FORCED_RMMOD
, LOCKDEP_NOW_UNRELIABLE
);
898 static inline int try_force_unload(unsigned int flags
)
902 #endif /* CONFIG_MODULE_FORCE_UNLOAD */
904 /* Try to release refcount of module, 0 means success. */
905 static int try_release_module_ref(struct module
*mod
)
909 /* Try to decrement refcnt which we set at loading */
910 ret
= atomic_sub_return(MODULE_REF_BASE
, &mod
->refcnt
);
913 /* Someone can put this right now, recover with checking */
914 ret
= atomic_add_unless(&mod
->refcnt
, MODULE_REF_BASE
, 0);
919 static int try_stop_module(struct module
*mod
, int flags
, int *forced
)
921 /* If it's not unused, quit unless we're forcing. */
922 if (try_release_module_ref(mod
) != 0) {
923 *forced
= try_force_unload(flags
);
928 /* Mark it as dying. */
929 mod
->state
= MODULE_STATE_GOING
;
935 * module_refcount - return the refcount or -1 if unloading
937 * @mod: the module we're checking
940 * -1 if the module is in the process of unloading
941 * otherwise the number of references in the kernel to the module
943 int module_refcount(struct module
*mod
)
945 return atomic_read(&mod
->refcnt
) - MODULE_REF_BASE
;
947 EXPORT_SYMBOL(module_refcount
);
949 /* This exists whether we can unload or not */
950 static void free_module(struct module
*mod
);
952 SYSCALL_DEFINE2(delete_module
, const char __user
*, name_user
,
956 char name
[MODULE_NAME_LEN
];
959 if (!capable(CAP_SYS_MODULE
) || modules_disabled
)
962 if (strncpy_from_user(name
, name_user
, MODULE_NAME_LEN
-1) < 0)
964 name
[MODULE_NAME_LEN
-1] = '\0';
966 audit_log_kern_module(name
);
968 if (mutex_lock_interruptible(&module_mutex
) != 0)
971 mod
= find_module(name
);
977 if (!list_empty(&mod
->source_list
)) {
978 /* Other modules depend on us: get rid of them first. */
983 /* Doing init or already dying? */
984 if (mod
->state
!= MODULE_STATE_LIVE
) {
985 /* FIXME: if (force), slam module count damn the torpedoes */
986 pr_debug("%s already dying\n", mod
->name
);
991 /* If it has an init func, it must have an exit func to unload */
992 if (mod
->init
&& !mod
->exit
) {
993 forced
= try_force_unload(flags
);
995 /* This module can't be removed */
1001 /* Stop the machine so refcounts can't move and disable module. */
1002 ret
= try_stop_module(mod
, flags
, &forced
);
1006 mutex_unlock(&module_mutex
);
1007 /* Final destruction now no one is using it. */
1008 if (mod
->exit
!= NULL
)
1010 blocking_notifier_call_chain(&module_notify_list
,
1011 MODULE_STATE_GOING
, mod
);
1012 klp_module_going(mod
);
1013 ftrace_release_mod(mod
);
1015 async_synchronize_full();
1017 /* Store the name of the last unloaded module for diagnostic purposes */
1018 strlcpy(last_unloaded_module
, mod
->name
, sizeof(last_unloaded_module
));
1023 mutex_unlock(&module_mutex
);
1027 static inline void print_unload_info(struct seq_file
*m
, struct module
*mod
)
1029 struct module_use
*use
;
1030 int printed_something
= 0;
1032 seq_printf(m
, " %i ", module_refcount(mod
));
1035 * Always include a trailing , so userspace can differentiate
1036 * between this and the old multi-field proc format.
1038 list_for_each_entry(use
, &mod
->source_list
, source_list
) {
1039 printed_something
= 1;
1040 seq_printf(m
, "%s,", use
->source
->name
);
1043 if (mod
->init
!= NULL
&& mod
->exit
== NULL
) {
1044 printed_something
= 1;
1045 seq_puts(m
, "[permanent],");
1048 if (!printed_something
)
1052 void __symbol_put(const char *symbol
)
1054 struct module
*owner
;
1057 if (!find_symbol(symbol
, &owner
, NULL
, true, false))
1062 EXPORT_SYMBOL(__symbol_put
);
1064 /* Note this assumes addr is a function, which it currently always is. */
1065 void symbol_put_addr(void *addr
)
1067 struct module
*modaddr
;
1068 unsigned long a
= (unsigned long)dereference_function_descriptor(addr
);
1070 if (core_kernel_text(a
))
1074 * Even though we hold a reference on the module; we still need to
1075 * disable preemption in order to safely traverse the data structure.
1078 modaddr
= __module_text_address(a
);
1080 module_put(modaddr
);
1083 EXPORT_SYMBOL_GPL(symbol_put_addr
);
1085 static ssize_t
show_refcnt(struct module_attribute
*mattr
,
1086 struct module_kobject
*mk
, char *buffer
)
1088 return sprintf(buffer
, "%i\n", module_refcount(mk
->mod
));
1091 static struct module_attribute modinfo_refcnt
=
1092 __ATTR(refcnt
, 0444, show_refcnt
, NULL
);
1094 void __module_get(struct module
*module
)
1098 atomic_inc(&module
->refcnt
);
1099 trace_module_get(module
, _RET_IP_
);
1103 EXPORT_SYMBOL(__module_get
);
1105 bool try_module_get(struct module
*module
)
1111 /* Note: here, we can fail to get a reference */
1112 if (likely(module_is_live(module
) &&
1113 atomic_inc_not_zero(&module
->refcnt
) != 0))
1114 trace_module_get(module
, _RET_IP_
);
1122 EXPORT_SYMBOL(try_module_get
);
1124 void module_put(struct module
*module
)
1130 ret
= atomic_dec_if_positive(&module
->refcnt
);
1131 WARN_ON(ret
< 0); /* Failed to put refcount */
1132 trace_module_put(module
, _RET_IP_
);
1136 EXPORT_SYMBOL(module_put
);
1138 #else /* !CONFIG_MODULE_UNLOAD */
1139 static inline void print_unload_info(struct seq_file
*m
, struct module
*mod
)
1141 /* We don't know the usage count, or what modules are using. */
1142 seq_puts(m
, " - -");
1145 static inline void module_unload_free(struct module
*mod
)
1149 int ref_module(struct module
*a
, struct module
*b
)
1151 return strong_try_module_get(b
);
1153 EXPORT_SYMBOL_GPL(ref_module
);
1155 static inline int module_unload_init(struct module
*mod
)
1159 #endif /* CONFIG_MODULE_UNLOAD */
1161 static size_t module_flags_taint(struct module
*mod
, char *buf
)
1166 for (i
= 0; i
< TAINT_FLAGS_COUNT
; i
++) {
1167 if (taint_flags
[i
].module
&& test_bit(i
, &mod
->taints
))
1168 buf
[l
++] = taint_flags
[i
].c_true
;
1174 static ssize_t
show_initstate(struct module_attribute
*mattr
,
1175 struct module_kobject
*mk
, char *buffer
)
1177 const char *state
= "unknown";
1179 switch (mk
->mod
->state
) {
1180 case MODULE_STATE_LIVE
:
1183 case MODULE_STATE_COMING
:
1186 case MODULE_STATE_GOING
:
1192 return sprintf(buffer
, "%s\n", state
);
1195 static struct module_attribute modinfo_initstate
=
1196 __ATTR(initstate
, 0444, show_initstate
, NULL
);
1198 static ssize_t
store_uevent(struct module_attribute
*mattr
,
1199 struct module_kobject
*mk
,
1200 const char *buffer
, size_t count
)
1202 enum kobject_action action
;
1204 if (kobject_action_type(buffer
, count
, &action
) == 0)
1205 kobject_uevent(&mk
->kobj
, action
);
1209 struct module_attribute module_uevent
=
1210 __ATTR(uevent
, 0200, NULL
, store_uevent
);
1212 static ssize_t
show_coresize(struct module_attribute
*mattr
,
1213 struct module_kobject
*mk
, char *buffer
)
1215 return sprintf(buffer
, "%u\n", mk
->mod
->core_layout
.size
);
1218 static struct module_attribute modinfo_coresize
=
1219 __ATTR(coresize
, 0444, show_coresize
, NULL
);
1221 static ssize_t
show_initsize(struct module_attribute
*mattr
,
1222 struct module_kobject
*mk
, char *buffer
)
1224 return sprintf(buffer
, "%u\n", mk
->mod
->init_layout
.size
);
1227 static struct module_attribute modinfo_initsize
=
1228 __ATTR(initsize
, 0444, show_initsize
, NULL
);
1230 static ssize_t
show_taint(struct module_attribute
*mattr
,
1231 struct module_kobject
*mk
, char *buffer
)
1235 l
= module_flags_taint(mk
->mod
, buffer
);
1240 static struct module_attribute modinfo_taint
=
1241 __ATTR(taint
, 0444, show_taint
, NULL
);
1243 static struct module_attribute
*modinfo_attrs
[] = {
1246 &modinfo_srcversion
,
1251 #ifdef CONFIG_MODULE_UNLOAD
1257 static const char vermagic
[] = VERMAGIC_STRING
;
1259 static int try_to_force_load(struct module
*mod
, const char *reason
)
1261 #ifdef CONFIG_MODULE_FORCE_LOAD
1262 if (!test_taint(TAINT_FORCED_MODULE
))
1263 pr_warn("%s: %s: kernel tainted.\n", mod
->name
, reason
);
1264 add_taint_module(mod
, TAINT_FORCED_MODULE
, LOCKDEP_NOW_UNRELIABLE
);
1271 #ifdef CONFIG_MODVERSIONS
1273 static u32
resolve_rel_crc(const s32
*crc
)
1275 return *(u32
*)((void *)crc
+ *crc
);
1278 static int check_version(Elf_Shdr
*sechdrs
,
1279 unsigned int versindex
,
1280 const char *symname
,
1284 unsigned int i
, num_versions
;
1285 struct modversion_info
*versions
;
1287 /* Exporting module didn't supply crcs? OK, we're already tainted. */
1291 /* No versions at all? modprobe --force does this. */
1293 return try_to_force_load(mod
, symname
) == 0;
1295 versions
= (void *) sechdrs
[versindex
].sh_addr
;
1296 num_versions
= sechdrs
[versindex
].sh_size
1297 / sizeof(struct modversion_info
);
1299 for (i
= 0; i
< num_versions
; i
++) {
1302 if (strcmp(versions
[i
].name
, symname
) != 0)
1305 if (IS_ENABLED(CONFIG_MODULE_REL_CRCS
))
1306 crcval
= resolve_rel_crc(crc
);
1309 if (versions
[i
].crc
== crcval
)
1311 pr_debug("Found checksum %X vs module %lX\n",
1312 crcval
, versions
[i
].crc
);
1316 /* Broken toolchain. Warn once, then let it go.. */
1317 pr_warn_once("%s: no symbol version for %s\n", mod
->name
, symname
);
1321 pr_warn("%s: disagrees about version of symbol %s\n",
1322 mod
->name
, symname
);
1326 static inline int check_modstruct_version(Elf_Shdr
*sechdrs
,
1327 unsigned int versindex
,
1333 * Since this should be found in kernel (which can't be removed), no
1334 * locking is necessary -- use preempt_disable() to placate lockdep.
1337 if (!find_symbol(VMLINUX_SYMBOL_STR(module_layout
), NULL
,
1338 &crc
, true, false)) {
1343 return check_version(sechdrs
, versindex
,
1344 VMLINUX_SYMBOL_STR(module_layout
), mod
, crc
);
1347 /* First part is kernel version, which we ignore if module has crcs. */
1348 static inline int same_magic(const char *amagic
, const char *bmagic
,
1352 amagic
+= strcspn(amagic
, " ");
1353 bmagic
+= strcspn(bmagic
, " ");
1355 return strcmp(amagic
, bmagic
) == 0;
1358 static inline int check_version(Elf_Shdr
*sechdrs
,
1359 unsigned int versindex
,
1360 const char *symname
,
1367 static inline int check_modstruct_version(Elf_Shdr
*sechdrs
,
1368 unsigned int versindex
,
1374 static inline int same_magic(const char *amagic
, const char *bmagic
,
1377 return strcmp(amagic
, bmagic
) == 0;
1379 #endif /* CONFIG_MODVERSIONS */
1381 /* Resolve a symbol for this module. I.e. if we find one, record usage. */
1382 static const struct kernel_symbol
*resolve_symbol(struct module
*mod
,
1383 const struct load_info
*info
,
1387 struct module
*owner
;
1388 const struct kernel_symbol
*sym
;
1393 * The module_mutex should not be a heavily contended lock;
1394 * if we get the occasional sleep here, we'll go an extra iteration
1395 * in the wait_event_interruptible(), which is harmless.
1397 sched_annotate_sleep();
1398 mutex_lock(&module_mutex
);
1399 sym
= find_symbol(name
, &owner
, &crc
,
1400 !(mod
->taints
& (1 << TAINT_PROPRIETARY_MODULE
)), true);
1404 if (!check_version(info
->sechdrs
, info
->index
.vers
, name
, mod
, crc
)) {
1405 sym
= ERR_PTR(-EINVAL
);
1409 err
= ref_module(mod
, owner
);
1416 /* We must make copy under the lock if we failed to get ref. */
1417 strncpy(ownername
, module_name(owner
), MODULE_NAME_LEN
);
1419 mutex_unlock(&module_mutex
);
1423 static const struct kernel_symbol
*
1424 resolve_symbol_wait(struct module
*mod
,
1425 const struct load_info
*info
,
1428 const struct kernel_symbol
*ksym
;
1429 char owner
[MODULE_NAME_LEN
];
1431 if (wait_event_interruptible_timeout(module_wq
,
1432 !IS_ERR(ksym
= resolve_symbol(mod
, info
, name
, owner
))
1433 || PTR_ERR(ksym
) != -EBUSY
,
1435 pr_warn("%s: gave up waiting for init of module %s.\n",
1442 * /sys/module/foo/sections stuff
1443 * J. Corbet <corbet@lwn.net>
1447 #ifdef CONFIG_KALLSYMS
1448 static inline bool sect_empty(const Elf_Shdr
*sect
)
1450 return !(sect
->sh_flags
& SHF_ALLOC
) || sect
->sh_size
== 0;
1453 struct module_sect_attr
{
1454 struct module_attribute mattr
;
1456 unsigned long address
;
1459 struct module_sect_attrs
{
1460 struct attribute_group grp
;
1461 unsigned int nsections
;
1462 struct module_sect_attr attrs
[0];
1465 static ssize_t
module_sect_show(struct module_attribute
*mattr
,
1466 struct module_kobject
*mk
, char *buf
)
1468 struct module_sect_attr
*sattr
=
1469 container_of(mattr
, struct module_sect_attr
, mattr
);
1470 return sprintf(buf
, "0x%pK\n", (void *)sattr
->address
);
1473 static void free_sect_attrs(struct module_sect_attrs
*sect_attrs
)
1475 unsigned int section
;
1477 for (section
= 0; section
< sect_attrs
->nsections
; section
++)
1478 kfree(sect_attrs
->attrs
[section
].name
);
1482 static void add_sect_attrs(struct module
*mod
, const struct load_info
*info
)
1484 unsigned int nloaded
= 0, i
, size
[2];
1485 struct module_sect_attrs
*sect_attrs
;
1486 struct module_sect_attr
*sattr
;
1487 struct attribute
**gattr
;
1489 /* Count loaded sections and allocate structures */
1490 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
1491 if (!sect_empty(&info
->sechdrs
[i
]))
1493 size
[0] = ALIGN(sizeof(*sect_attrs
)
1494 + nloaded
* sizeof(sect_attrs
->attrs
[0]),
1495 sizeof(sect_attrs
->grp
.attrs
[0]));
1496 size
[1] = (nloaded
+ 1) * sizeof(sect_attrs
->grp
.attrs
[0]);
1497 sect_attrs
= kzalloc(size
[0] + size
[1], GFP_KERNEL
);
1498 if (sect_attrs
== NULL
)
1501 /* Setup section attributes. */
1502 sect_attrs
->grp
.name
= "sections";
1503 sect_attrs
->grp
.attrs
= (void *)sect_attrs
+ size
[0];
1505 sect_attrs
->nsections
= 0;
1506 sattr
= §_attrs
->attrs
[0];
1507 gattr
= §_attrs
->grp
.attrs
[0];
1508 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++) {
1509 Elf_Shdr
*sec
= &info
->sechdrs
[i
];
1510 if (sect_empty(sec
))
1512 sattr
->address
= sec
->sh_addr
;
1513 sattr
->name
= kstrdup(info
->secstrings
+ sec
->sh_name
,
1515 if (sattr
->name
== NULL
)
1517 sect_attrs
->nsections
++;
1518 sysfs_attr_init(&sattr
->mattr
.attr
);
1519 sattr
->mattr
.show
= module_sect_show
;
1520 sattr
->mattr
.store
= NULL
;
1521 sattr
->mattr
.attr
.name
= sattr
->name
;
1522 sattr
->mattr
.attr
.mode
= S_IRUGO
;
1523 *(gattr
++) = &(sattr
++)->mattr
.attr
;
1527 if (sysfs_create_group(&mod
->mkobj
.kobj
, §_attrs
->grp
))
1530 mod
->sect_attrs
= sect_attrs
;
1533 free_sect_attrs(sect_attrs
);
1536 static void remove_sect_attrs(struct module
*mod
)
1538 if (mod
->sect_attrs
) {
1539 sysfs_remove_group(&mod
->mkobj
.kobj
,
1540 &mod
->sect_attrs
->grp
);
1541 /* We are positive that no one is using any sect attrs
1542 * at this point. Deallocate immediately. */
1543 free_sect_attrs(mod
->sect_attrs
);
1544 mod
->sect_attrs
= NULL
;
1549 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1552 struct module_notes_attrs
{
1553 struct kobject
*dir
;
1555 struct bin_attribute attrs
[0];
1558 static ssize_t
module_notes_read(struct file
*filp
, struct kobject
*kobj
,
1559 struct bin_attribute
*bin_attr
,
1560 char *buf
, loff_t pos
, size_t count
)
1563 * The caller checked the pos and count against our size.
1565 memcpy(buf
, bin_attr
->private + pos
, count
);
1569 static void free_notes_attrs(struct module_notes_attrs
*notes_attrs
,
1572 if (notes_attrs
->dir
) {
1574 sysfs_remove_bin_file(notes_attrs
->dir
,
1575 ¬es_attrs
->attrs
[i
]);
1576 kobject_put(notes_attrs
->dir
);
1581 static void add_notes_attrs(struct module
*mod
, const struct load_info
*info
)
1583 unsigned int notes
, loaded
, i
;
1584 struct module_notes_attrs
*notes_attrs
;
1585 struct bin_attribute
*nattr
;
1587 /* failed to create section attributes, so can't create notes */
1588 if (!mod
->sect_attrs
)
1591 /* Count notes sections and allocate structures. */
1593 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
1594 if (!sect_empty(&info
->sechdrs
[i
]) &&
1595 (info
->sechdrs
[i
].sh_type
== SHT_NOTE
))
1601 notes_attrs
= kzalloc(sizeof(*notes_attrs
)
1602 + notes
* sizeof(notes_attrs
->attrs
[0]),
1604 if (notes_attrs
== NULL
)
1607 notes_attrs
->notes
= notes
;
1608 nattr
= ¬es_attrs
->attrs
[0];
1609 for (loaded
= i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
1610 if (sect_empty(&info
->sechdrs
[i
]))
1612 if (info
->sechdrs
[i
].sh_type
== SHT_NOTE
) {
1613 sysfs_bin_attr_init(nattr
);
1614 nattr
->attr
.name
= mod
->sect_attrs
->attrs
[loaded
].name
;
1615 nattr
->attr
.mode
= S_IRUGO
;
1616 nattr
->size
= info
->sechdrs
[i
].sh_size
;
1617 nattr
->private = (void *) info
->sechdrs
[i
].sh_addr
;
1618 nattr
->read
= module_notes_read
;
1624 notes_attrs
->dir
= kobject_create_and_add("notes", &mod
->mkobj
.kobj
);
1625 if (!notes_attrs
->dir
)
1628 for (i
= 0; i
< notes
; ++i
)
1629 if (sysfs_create_bin_file(notes_attrs
->dir
,
1630 ¬es_attrs
->attrs
[i
]))
1633 mod
->notes_attrs
= notes_attrs
;
1637 free_notes_attrs(notes_attrs
, i
);
1640 static void remove_notes_attrs(struct module
*mod
)
1642 if (mod
->notes_attrs
)
1643 free_notes_attrs(mod
->notes_attrs
, mod
->notes_attrs
->notes
);
1648 static inline void add_sect_attrs(struct module
*mod
,
1649 const struct load_info
*info
)
1653 static inline void remove_sect_attrs(struct module
*mod
)
1657 static inline void add_notes_attrs(struct module
*mod
,
1658 const struct load_info
*info
)
1662 static inline void remove_notes_attrs(struct module
*mod
)
1665 #endif /* CONFIG_KALLSYMS */
1667 static void add_usage_links(struct module
*mod
)
1669 #ifdef CONFIG_MODULE_UNLOAD
1670 struct module_use
*use
;
1673 mutex_lock(&module_mutex
);
1674 list_for_each_entry(use
, &mod
->target_list
, target_list
) {
1675 nowarn
= sysfs_create_link(use
->target
->holders_dir
,
1676 &mod
->mkobj
.kobj
, mod
->name
);
1678 mutex_unlock(&module_mutex
);
1682 static void del_usage_links(struct module
*mod
)
1684 #ifdef CONFIG_MODULE_UNLOAD
1685 struct module_use
*use
;
1687 mutex_lock(&module_mutex
);
1688 list_for_each_entry(use
, &mod
->target_list
, target_list
)
1689 sysfs_remove_link(use
->target
->holders_dir
, mod
->name
);
1690 mutex_unlock(&module_mutex
);
1694 static int module_add_modinfo_attrs(struct module
*mod
)
1696 struct module_attribute
*attr
;
1697 struct module_attribute
*temp_attr
;
1701 mod
->modinfo_attrs
= kzalloc((sizeof(struct module_attribute
) *
1702 (ARRAY_SIZE(modinfo_attrs
) + 1)),
1704 if (!mod
->modinfo_attrs
)
1707 temp_attr
= mod
->modinfo_attrs
;
1708 for (i
= 0; (attr
= modinfo_attrs
[i
]) && !error
; i
++) {
1709 if (!attr
->test
|| attr
->test(mod
)) {
1710 memcpy(temp_attr
, attr
, sizeof(*temp_attr
));
1711 sysfs_attr_init(&temp_attr
->attr
);
1712 error
= sysfs_create_file(&mod
->mkobj
.kobj
,
1720 static void module_remove_modinfo_attrs(struct module
*mod
)
1722 struct module_attribute
*attr
;
1725 for (i
= 0; (attr
= &mod
->modinfo_attrs
[i
]); i
++) {
1726 /* pick a field to test for end of list */
1727 if (!attr
->attr
.name
)
1729 sysfs_remove_file(&mod
->mkobj
.kobj
, &attr
->attr
);
1733 kfree(mod
->modinfo_attrs
);
1736 static void mod_kobject_put(struct module
*mod
)
1738 DECLARE_COMPLETION_ONSTACK(c
);
1739 mod
->mkobj
.kobj_completion
= &c
;
1740 kobject_put(&mod
->mkobj
.kobj
);
1741 wait_for_completion(&c
);
1744 static int mod_sysfs_init(struct module
*mod
)
1747 struct kobject
*kobj
;
1749 if (!module_sysfs_initialized
) {
1750 pr_err("%s: module sysfs not initialized\n", mod
->name
);
1755 kobj
= kset_find_obj(module_kset
, mod
->name
);
1757 pr_err("%s: module is already loaded\n", mod
->name
);
1763 mod
->mkobj
.mod
= mod
;
1765 memset(&mod
->mkobj
.kobj
, 0, sizeof(mod
->mkobj
.kobj
));
1766 mod
->mkobj
.kobj
.kset
= module_kset
;
1767 err
= kobject_init_and_add(&mod
->mkobj
.kobj
, &module_ktype
, NULL
,
1770 mod_kobject_put(mod
);
1772 /* delay uevent until full sysfs population */
1777 static int mod_sysfs_setup(struct module
*mod
,
1778 const struct load_info
*info
,
1779 struct kernel_param
*kparam
,
1780 unsigned int num_params
)
1784 err
= mod_sysfs_init(mod
);
1788 mod
->holders_dir
= kobject_create_and_add("holders", &mod
->mkobj
.kobj
);
1789 if (!mod
->holders_dir
) {
1794 err
= module_param_sysfs_setup(mod
, kparam
, num_params
);
1796 goto out_unreg_holders
;
1798 err
= module_add_modinfo_attrs(mod
);
1800 goto out_unreg_param
;
1802 add_usage_links(mod
);
1803 add_sect_attrs(mod
, info
);
1804 add_notes_attrs(mod
, info
);
1806 kobject_uevent(&mod
->mkobj
.kobj
, KOBJ_ADD
);
1810 module_param_sysfs_remove(mod
);
1812 kobject_put(mod
->holders_dir
);
1814 mod_kobject_put(mod
);
1819 static void mod_sysfs_fini(struct module
*mod
)
1821 remove_notes_attrs(mod
);
1822 remove_sect_attrs(mod
);
1823 mod_kobject_put(mod
);
1826 static void init_param_lock(struct module
*mod
)
1828 mutex_init(&mod
->param_lock
);
1830 #else /* !CONFIG_SYSFS */
1832 static int mod_sysfs_setup(struct module
*mod
,
1833 const struct load_info
*info
,
1834 struct kernel_param
*kparam
,
1835 unsigned int num_params
)
1840 static void mod_sysfs_fini(struct module
*mod
)
1844 static void module_remove_modinfo_attrs(struct module
*mod
)
1848 static void del_usage_links(struct module
*mod
)
1852 static void init_param_lock(struct module
*mod
)
1855 #endif /* CONFIG_SYSFS */
1857 static void mod_sysfs_teardown(struct module
*mod
)
1859 del_usage_links(mod
);
1860 module_remove_modinfo_attrs(mod
);
1861 module_param_sysfs_remove(mod
);
1862 kobject_put(mod
->mkobj
.drivers_dir
);
1863 kobject_put(mod
->holders_dir
);
1864 mod_sysfs_fini(mod
);
1867 #ifdef CONFIG_STRICT_MODULE_RWX
1869 * LKM RO/NX protection: protect module's text/ro-data
1870 * from modification and any data from execution.
1872 * General layout of module is:
1873 * [text] [read-only-data] [ro-after-init] [writable data]
1874 * text_size -----^ ^ ^ ^
1875 * ro_size ------------------------| | |
1876 * ro_after_init_size -----------------------------| |
1877 * size -----------------------------------------------------------|
1879 * These values are always page-aligned (as is base)
1881 static void frob_text(const struct module_layout
*layout
,
1882 int (*set_memory
)(unsigned long start
, int num_pages
))
1884 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1885 BUG_ON((unsigned long)layout
->text_size
& (PAGE_SIZE
-1));
1886 set_memory((unsigned long)layout
->base
,
1887 layout
->text_size
>> PAGE_SHIFT
);
1890 static void frob_rodata(const struct module_layout
*layout
,
1891 int (*set_memory
)(unsigned long start
, int num_pages
))
1893 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1894 BUG_ON((unsigned long)layout
->text_size
& (PAGE_SIZE
-1));
1895 BUG_ON((unsigned long)layout
->ro_size
& (PAGE_SIZE
-1));
1896 set_memory((unsigned long)layout
->base
+ layout
->text_size
,
1897 (layout
->ro_size
- layout
->text_size
) >> PAGE_SHIFT
);
1900 static void frob_ro_after_init(const struct module_layout
*layout
,
1901 int (*set_memory
)(unsigned long start
, int num_pages
))
1903 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1904 BUG_ON((unsigned long)layout
->ro_size
& (PAGE_SIZE
-1));
1905 BUG_ON((unsigned long)layout
->ro_after_init_size
& (PAGE_SIZE
-1));
1906 set_memory((unsigned long)layout
->base
+ layout
->ro_size
,
1907 (layout
->ro_after_init_size
- layout
->ro_size
) >> PAGE_SHIFT
);
1910 static void frob_writable_data(const struct module_layout
*layout
,
1911 int (*set_memory
)(unsigned long start
, int num_pages
))
1913 BUG_ON((unsigned long)layout
->base
& (PAGE_SIZE
-1));
1914 BUG_ON((unsigned long)layout
->ro_after_init_size
& (PAGE_SIZE
-1));
1915 BUG_ON((unsigned long)layout
->size
& (PAGE_SIZE
-1));
1916 set_memory((unsigned long)layout
->base
+ layout
->ro_after_init_size
,
1917 (layout
->size
- layout
->ro_after_init_size
) >> PAGE_SHIFT
);
1920 /* livepatching wants to disable read-only so it can frob module. */
1921 void module_disable_ro(const struct module
*mod
)
1923 if (!rodata_enabled
)
1926 frob_text(&mod
->core_layout
, set_memory_rw
);
1927 frob_rodata(&mod
->core_layout
, set_memory_rw
);
1928 frob_ro_after_init(&mod
->core_layout
, set_memory_rw
);
1929 frob_text(&mod
->init_layout
, set_memory_rw
);
1930 frob_rodata(&mod
->init_layout
, set_memory_rw
);
1933 void module_enable_ro(const struct module
*mod
, bool after_init
)
1935 if (!rodata_enabled
)
1938 frob_text(&mod
->core_layout
, set_memory_ro
);
1939 frob_rodata(&mod
->core_layout
, set_memory_ro
);
1940 frob_text(&mod
->init_layout
, set_memory_ro
);
1941 frob_rodata(&mod
->init_layout
, set_memory_ro
);
1944 frob_ro_after_init(&mod
->core_layout
, set_memory_ro
);
1947 static void module_enable_nx(const struct module
*mod
)
1949 frob_rodata(&mod
->core_layout
, set_memory_nx
);
1950 frob_ro_after_init(&mod
->core_layout
, set_memory_nx
);
1951 frob_writable_data(&mod
->core_layout
, set_memory_nx
);
1952 frob_rodata(&mod
->init_layout
, set_memory_nx
);
1953 frob_writable_data(&mod
->init_layout
, set_memory_nx
);
1956 static void module_disable_nx(const struct module
*mod
)
1958 frob_rodata(&mod
->core_layout
, set_memory_x
);
1959 frob_ro_after_init(&mod
->core_layout
, set_memory_x
);
1960 frob_writable_data(&mod
->core_layout
, set_memory_x
);
1961 frob_rodata(&mod
->init_layout
, set_memory_x
);
1962 frob_writable_data(&mod
->init_layout
, set_memory_x
);
1965 /* Iterate through all modules and set each module's text as RW */
1966 void set_all_modules_text_rw(void)
1970 if (!rodata_enabled
)
1973 mutex_lock(&module_mutex
);
1974 list_for_each_entry_rcu(mod
, &modules
, list
) {
1975 if (mod
->state
== MODULE_STATE_UNFORMED
)
1978 frob_text(&mod
->core_layout
, set_memory_rw
);
1979 frob_text(&mod
->init_layout
, set_memory_rw
);
1981 mutex_unlock(&module_mutex
);
1984 /* Iterate through all modules and set each module's text as RO */
1985 void set_all_modules_text_ro(void)
1989 if (!rodata_enabled
)
1992 mutex_lock(&module_mutex
);
1993 list_for_each_entry_rcu(mod
, &modules
, list
) {
1995 * Ignore going modules since it's possible that ro
1996 * protection has already been disabled, otherwise we'll
1997 * run into protection faults at module deallocation.
1999 if (mod
->state
== MODULE_STATE_UNFORMED
||
2000 mod
->state
== MODULE_STATE_GOING
)
2003 frob_text(&mod
->core_layout
, set_memory_ro
);
2004 frob_text(&mod
->init_layout
, set_memory_ro
);
2006 mutex_unlock(&module_mutex
);
2009 static void disable_ro_nx(const struct module_layout
*layout
)
2011 if (rodata_enabled
) {
2012 frob_text(layout
, set_memory_rw
);
2013 frob_rodata(layout
, set_memory_rw
);
2014 frob_ro_after_init(layout
, set_memory_rw
);
2016 frob_rodata(layout
, set_memory_x
);
2017 frob_ro_after_init(layout
, set_memory_x
);
2018 frob_writable_data(layout
, set_memory_x
);
2022 static void disable_ro_nx(const struct module_layout
*layout
) { }
2023 static void module_enable_nx(const struct module
*mod
) { }
2024 static void module_disable_nx(const struct module
*mod
) { }
2027 #ifdef CONFIG_LIVEPATCH
2029 * Persist Elf information about a module. Copy the Elf header,
2030 * section header table, section string table, and symtab section
2031 * index from info to mod->klp_info.
2033 static int copy_module_elf(struct module
*mod
, struct load_info
*info
)
2035 unsigned int size
, symndx
;
2038 size
= sizeof(*mod
->klp_info
);
2039 mod
->klp_info
= kmalloc(size
, GFP_KERNEL
);
2040 if (mod
->klp_info
== NULL
)
2044 size
= sizeof(mod
->klp_info
->hdr
);
2045 memcpy(&mod
->klp_info
->hdr
, info
->hdr
, size
);
2047 /* Elf section header table */
2048 size
= sizeof(*info
->sechdrs
) * info
->hdr
->e_shnum
;
2049 mod
->klp_info
->sechdrs
= kmalloc(size
, GFP_KERNEL
);
2050 if (mod
->klp_info
->sechdrs
== NULL
) {
2054 memcpy(mod
->klp_info
->sechdrs
, info
->sechdrs
, size
);
2056 /* Elf section name string table */
2057 size
= info
->sechdrs
[info
->hdr
->e_shstrndx
].sh_size
;
2058 mod
->klp_info
->secstrings
= kmalloc(size
, GFP_KERNEL
);
2059 if (mod
->klp_info
->secstrings
== NULL
) {
2063 memcpy(mod
->klp_info
->secstrings
, info
->secstrings
, size
);
2065 /* Elf symbol section index */
2066 symndx
= info
->index
.sym
;
2067 mod
->klp_info
->symndx
= symndx
;
2070 * For livepatch modules, core_kallsyms.symtab is a complete
2071 * copy of the original symbol table. Adjust sh_addr to point
2072 * to core_kallsyms.symtab since the copy of the symtab in module
2073 * init memory is freed at the end of do_init_module().
2075 mod
->klp_info
->sechdrs
[symndx
].sh_addr
= \
2076 (unsigned long) mod
->core_kallsyms
.symtab
;
2081 kfree(mod
->klp_info
->sechdrs
);
2083 kfree(mod
->klp_info
);
2087 static void free_module_elf(struct module
*mod
)
2089 kfree(mod
->klp_info
->sechdrs
);
2090 kfree(mod
->klp_info
->secstrings
);
2091 kfree(mod
->klp_info
);
2093 #else /* !CONFIG_LIVEPATCH */
2094 static int copy_module_elf(struct module
*mod
, struct load_info
*info
)
2099 static void free_module_elf(struct module
*mod
)
2102 #endif /* CONFIG_LIVEPATCH */
2104 void __weak
module_memfree(void *module_region
)
2106 vfree(module_region
);
2109 void __weak
module_arch_cleanup(struct module
*mod
)
2113 void __weak
module_arch_freeing_init(struct module
*mod
)
2117 /* Free a module, remove from lists, etc. */
2118 static void free_module(struct module
*mod
)
2120 trace_module_free(mod
);
2122 mod_sysfs_teardown(mod
);
2124 /* We leave it in list to prevent duplicate loads, but make sure
2125 * that noone uses it while it's being deconstructed. */
2126 mutex_lock(&module_mutex
);
2127 mod
->state
= MODULE_STATE_UNFORMED
;
2128 mutex_unlock(&module_mutex
);
2130 /* Remove dynamic debug info */
2131 ddebug_remove_module(mod
->name
);
2133 /* Arch-specific cleanup. */
2134 module_arch_cleanup(mod
);
2136 /* Module unload stuff */
2137 module_unload_free(mod
);
2139 /* Free any allocated parameters. */
2140 destroy_params(mod
->kp
, mod
->num_kp
);
2142 if (is_livepatch_module(mod
))
2143 free_module_elf(mod
);
2145 /* Now we can delete it from the lists */
2146 mutex_lock(&module_mutex
);
2147 /* Unlink carefully: kallsyms could be walking list. */
2148 list_del_rcu(&mod
->list
);
2149 mod_tree_remove(mod
);
2150 /* Remove this module from bug list, this uses list_del_rcu */
2151 module_bug_cleanup(mod
);
2152 /* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */
2153 synchronize_sched();
2154 mutex_unlock(&module_mutex
);
2156 /* This may be empty, but that's OK */
2157 disable_ro_nx(&mod
->init_layout
);
2158 module_arch_freeing_init(mod
);
2159 module_memfree(mod
->init_layout
.base
);
2161 percpu_modfree(mod
);
2163 /* Free lock-classes; relies on the preceding sync_rcu(). */
2164 lockdep_free_key_range(mod
->core_layout
.base
, mod
->core_layout
.size
);
2166 /* Finally, free the core (containing the module structure) */
2167 disable_ro_nx(&mod
->core_layout
);
2168 module_memfree(mod
->core_layout
.base
);
2171 update_protections(current
->mm
);
2175 void *__symbol_get(const char *symbol
)
2177 struct module
*owner
;
2178 const struct kernel_symbol
*sym
;
2181 sym
= find_symbol(symbol
, &owner
, NULL
, true, true);
2182 if (sym
&& strong_try_module_get(owner
))
2186 return sym
? (void *)sym
->value
: NULL
;
2188 EXPORT_SYMBOL_GPL(__symbol_get
);
2191 * Ensure that an exported symbol [global namespace] does not already exist
2192 * in the kernel or in some other module's exported symbol table.
2194 * You must hold the module_mutex.
2196 static int verify_export_symbols(struct module
*mod
)
2199 struct module
*owner
;
2200 const struct kernel_symbol
*s
;
2202 const struct kernel_symbol
*sym
;
2205 { mod
->syms
, mod
->num_syms
},
2206 { mod
->gpl_syms
, mod
->num_gpl_syms
},
2207 { mod
->gpl_future_syms
, mod
->num_gpl_future_syms
},
2208 #ifdef CONFIG_UNUSED_SYMBOLS
2209 { mod
->unused_syms
, mod
->num_unused_syms
},
2210 { mod
->unused_gpl_syms
, mod
->num_unused_gpl_syms
},
2214 for (i
= 0; i
< ARRAY_SIZE(arr
); i
++) {
2215 for (s
= arr
[i
].sym
; s
< arr
[i
].sym
+ arr
[i
].num
; s
++) {
2216 if (find_symbol(s
->name
, &owner
, NULL
, true, false)) {
2217 pr_err("%s: exports duplicate symbol %s"
2219 mod
->name
, s
->name
, module_name(owner
));
2227 /* Change all symbols so that st_value encodes the pointer directly. */
2228 static int simplify_symbols(struct module
*mod
, const struct load_info
*info
)
2230 Elf_Shdr
*symsec
= &info
->sechdrs
[info
->index
.sym
];
2231 Elf_Sym
*sym
= (void *)symsec
->sh_addr
;
2232 unsigned long secbase
;
2235 const struct kernel_symbol
*ksym
;
2237 for (i
= 1; i
< symsec
->sh_size
/ sizeof(Elf_Sym
); i
++) {
2238 const char *name
= info
->strtab
+ sym
[i
].st_name
;
2240 switch (sym
[i
].st_shndx
) {
2242 /* Ignore common symbols */
2243 if (!strncmp(name
, "__gnu_lto", 9))
2246 /* We compiled with -fno-common. These are not
2247 supposed to happen. */
2248 pr_debug("Common symbol: %s\n", name
);
2249 pr_warn("%s: please compile with -fno-common\n",
2255 /* Don't need to do anything */
2256 pr_debug("Absolute symbol: 0x%08lx\n",
2257 (long)sym
[i
].st_value
);
2261 /* Livepatch symbols are resolved by livepatch */
2265 ksym
= resolve_symbol_wait(mod
, info
, name
);
2266 /* Ok if resolved. */
2267 if (ksym
&& !IS_ERR(ksym
)) {
2268 sym
[i
].st_value
= ksym
->value
;
2273 if (!ksym
&& ELF_ST_BIND(sym
[i
].st_info
) == STB_WEAK
)
2276 pr_warn("%s: Unknown symbol %s (err %li)\n",
2277 mod
->name
, name
, PTR_ERR(ksym
));
2278 ret
= PTR_ERR(ksym
) ?: -ENOENT
;
2282 /* Divert to percpu allocation if a percpu var. */
2283 if (sym
[i
].st_shndx
== info
->index
.pcpu
)
2284 secbase
= (unsigned long)mod_percpu(mod
);
2286 secbase
= info
->sechdrs
[sym
[i
].st_shndx
].sh_addr
;
2287 sym
[i
].st_value
+= secbase
;
2295 static int apply_relocations(struct module
*mod
, const struct load_info
*info
)
2300 /* Now do relocations. */
2301 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2302 unsigned int infosec
= info
->sechdrs
[i
].sh_info
;
2304 /* Not a valid relocation section? */
2305 if (infosec
>= info
->hdr
->e_shnum
)
2308 /* Don't bother with non-allocated sections */
2309 if (!(info
->sechdrs
[infosec
].sh_flags
& SHF_ALLOC
))
2312 /* Livepatch relocation sections are applied by livepatch */
2313 if (info
->sechdrs
[i
].sh_flags
& SHF_RELA_LIVEPATCH
)
2316 if (info
->sechdrs
[i
].sh_type
== SHT_REL
)
2317 err
= apply_relocate(info
->sechdrs
, info
->strtab
,
2318 info
->index
.sym
, i
, mod
);
2319 else if (info
->sechdrs
[i
].sh_type
== SHT_RELA
)
2320 err
= apply_relocate_add(info
->sechdrs
, info
->strtab
,
2321 info
->index
.sym
, i
, mod
);
2328 /* Additional bytes needed by arch in front of individual sections */
2329 unsigned int __weak
arch_mod_section_prepend(struct module
*mod
,
2330 unsigned int section
)
2332 /* default implementation just returns zero */
2336 /* Update size with this section: return offset. */
2337 static long get_offset(struct module
*mod
, unsigned int *size
,
2338 Elf_Shdr
*sechdr
, unsigned int section
)
2342 *size
+= arch_mod_section_prepend(mod
, section
);
2343 ret
= ALIGN(*size
, sechdr
->sh_addralign
?: 1);
2344 *size
= ret
+ sechdr
->sh_size
;
2348 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
2349 might -- code, read-only data, read-write data, small data. Tally
2350 sizes, and place the offsets into sh_entsize fields: high bit means it
2352 static void layout_sections(struct module
*mod
, struct load_info
*info
)
2354 static unsigned long const masks
[][2] = {
2355 /* NOTE: all executable code must be the first section
2356 * in this array; otherwise modify the text_size
2357 * finder in the two loops below */
2358 { SHF_EXECINSTR
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2359 { SHF_ALLOC
, SHF_WRITE
| ARCH_SHF_SMALL
},
2360 { SHF_RO_AFTER_INIT
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2361 { SHF_WRITE
| SHF_ALLOC
, ARCH_SHF_SMALL
},
2362 { ARCH_SHF_SMALL
| SHF_ALLOC
, 0 }
2366 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++)
2367 info
->sechdrs
[i
].sh_entsize
= ~0UL;
2369 pr_debug("Core section allocation order:\n");
2370 for (m
= 0; m
< ARRAY_SIZE(masks
); ++m
) {
2371 for (i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
2372 Elf_Shdr
*s
= &info
->sechdrs
[i
];
2373 const char *sname
= info
->secstrings
+ s
->sh_name
;
2375 if ((s
->sh_flags
& masks
[m
][0]) != masks
[m
][0]
2376 || (s
->sh_flags
& masks
[m
][1])
2377 || s
->sh_entsize
!= ~0UL
2378 || strstarts(sname
, ".init"))
2380 s
->sh_entsize
= get_offset(mod
, &mod
->core_layout
.size
, s
, i
);
2381 pr_debug("\t%s\n", sname
);
2384 case 0: /* executable */
2385 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2386 mod
->core_layout
.text_size
= mod
->core_layout
.size
;
2388 case 1: /* RO: text and ro-data */
2389 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2390 mod
->core_layout
.ro_size
= mod
->core_layout
.size
;
2392 case 2: /* RO after init */
2393 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2394 mod
->core_layout
.ro_after_init_size
= mod
->core_layout
.size
;
2396 case 4: /* whole core */
2397 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2402 pr_debug("Init section allocation order:\n");
2403 for (m
= 0; m
< ARRAY_SIZE(masks
); ++m
) {
2404 for (i
= 0; i
< info
->hdr
->e_shnum
; ++i
) {
2405 Elf_Shdr
*s
= &info
->sechdrs
[i
];
2406 const char *sname
= info
->secstrings
+ s
->sh_name
;
2408 if ((s
->sh_flags
& masks
[m
][0]) != masks
[m
][0]
2409 || (s
->sh_flags
& masks
[m
][1])
2410 || s
->sh_entsize
!= ~0UL
2411 || !strstarts(sname
, ".init"))
2413 s
->sh_entsize
= (get_offset(mod
, &mod
->init_layout
.size
, s
, i
)
2414 | INIT_OFFSET_MASK
);
2415 pr_debug("\t%s\n", sname
);
2418 case 0: /* executable */
2419 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2420 mod
->init_layout
.text_size
= mod
->init_layout
.size
;
2422 case 1: /* RO: text and ro-data */
2423 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2424 mod
->init_layout
.ro_size
= mod
->init_layout
.size
;
2428 * RO after init doesn't apply to init_layout (only
2429 * core_layout), so it just takes the value of ro_size.
2431 mod
->init_layout
.ro_after_init_size
= mod
->init_layout
.ro_size
;
2433 case 4: /* whole init */
2434 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2440 static void set_license(struct module
*mod
, const char *license
)
2443 license
= "unspecified";
2445 if (!license_is_gpl_compatible(license
)) {
2446 if (!test_taint(TAINT_PROPRIETARY_MODULE
))
2447 pr_warn("%s: module license '%s' taints kernel.\n",
2448 mod
->name
, license
);
2449 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
2450 LOCKDEP_NOW_UNRELIABLE
);
2454 /* Parse tag=value strings from .modinfo section */
2455 static char *next_string(char *string
, unsigned long *secsize
)
2457 /* Skip non-zero chars */
2460 if ((*secsize
)-- <= 1)
2464 /* Skip any zero padding. */
2465 while (!string
[0]) {
2467 if ((*secsize
)-- <= 1)
2473 static char *get_modinfo(struct load_info
*info
, const char *tag
)
2476 unsigned int taglen
= strlen(tag
);
2477 Elf_Shdr
*infosec
= &info
->sechdrs
[info
->index
.info
];
2478 unsigned long size
= infosec
->sh_size
;
2480 for (p
= (char *)infosec
->sh_addr
; p
; p
= next_string(p
, &size
)) {
2481 if (strncmp(p
, tag
, taglen
) == 0 && p
[taglen
] == '=')
2482 return p
+ taglen
+ 1;
2487 static void setup_modinfo(struct module
*mod
, struct load_info
*info
)
2489 struct module_attribute
*attr
;
2492 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
2494 attr
->setup(mod
, get_modinfo(info
, attr
->attr
.name
));
2498 static void free_modinfo(struct module
*mod
)
2500 struct module_attribute
*attr
;
2503 for (i
= 0; (attr
= modinfo_attrs
[i
]); i
++) {
2509 #ifdef CONFIG_KALLSYMS
2511 /* lookup symbol in given range of kernel_symbols */
2512 static const struct kernel_symbol
*lookup_symbol(const char *name
,
2513 const struct kernel_symbol
*start
,
2514 const struct kernel_symbol
*stop
)
2516 return bsearch(name
, start
, stop
- start
,
2517 sizeof(struct kernel_symbol
), cmp_name
);
2520 static int is_exported(const char *name
, unsigned long value
,
2521 const struct module
*mod
)
2523 const struct kernel_symbol
*ks
;
2525 ks
= lookup_symbol(name
, __start___ksymtab
, __stop___ksymtab
);
2527 ks
= lookup_symbol(name
, mod
->syms
, mod
->syms
+ mod
->num_syms
);
2528 return ks
!= NULL
&& ks
->value
== value
;
2532 static char elf_type(const Elf_Sym
*sym
, const struct load_info
*info
)
2534 const Elf_Shdr
*sechdrs
= info
->sechdrs
;
2536 if (ELF_ST_BIND(sym
->st_info
) == STB_WEAK
) {
2537 if (ELF_ST_TYPE(sym
->st_info
) == STT_OBJECT
)
2542 if (sym
->st_shndx
== SHN_UNDEF
)
2544 if (sym
->st_shndx
== SHN_ABS
|| sym
->st_shndx
== info
->index
.pcpu
)
2546 if (sym
->st_shndx
>= SHN_LORESERVE
)
2548 if (sechdrs
[sym
->st_shndx
].sh_flags
& SHF_EXECINSTR
)
2550 if (sechdrs
[sym
->st_shndx
].sh_flags
& SHF_ALLOC
2551 && sechdrs
[sym
->st_shndx
].sh_type
!= SHT_NOBITS
) {
2552 if (!(sechdrs
[sym
->st_shndx
].sh_flags
& SHF_WRITE
))
2554 else if (sechdrs
[sym
->st_shndx
].sh_flags
& ARCH_SHF_SMALL
)
2559 if (sechdrs
[sym
->st_shndx
].sh_type
== SHT_NOBITS
) {
2560 if (sechdrs
[sym
->st_shndx
].sh_flags
& ARCH_SHF_SMALL
)
2565 if (strstarts(info
->secstrings
+ sechdrs
[sym
->st_shndx
].sh_name
,
2572 static bool is_core_symbol(const Elf_Sym
*src
, const Elf_Shdr
*sechdrs
,
2573 unsigned int shnum
, unsigned int pcpundx
)
2575 const Elf_Shdr
*sec
;
2577 if (src
->st_shndx
== SHN_UNDEF
2578 || src
->st_shndx
>= shnum
2582 #ifdef CONFIG_KALLSYMS_ALL
2583 if (src
->st_shndx
== pcpundx
)
2587 sec
= sechdrs
+ src
->st_shndx
;
2588 if (!(sec
->sh_flags
& SHF_ALLOC
)
2589 #ifndef CONFIG_KALLSYMS_ALL
2590 || !(sec
->sh_flags
& SHF_EXECINSTR
)
2592 || (sec
->sh_entsize
& INIT_OFFSET_MASK
))
2599 * We only allocate and copy the strings needed by the parts of symtab
2600 * we keep. This is simple, but has the effect of making multiple
2601 * copies of duplicates. We could be more sophisticated, see
2602 * linux-kernel thread starting with
2603 * <73defb5e4bca04a6431392cc341112b1@localhost>.
2605 static void layout_symtab(struct module
*mod
, struct load_info
*info
)
2607 Elf_Shdr
*symsect
= info
->sechdrs
+ info
->index
.sym
;
2608 Elf_Shdr
*strsect
= info
->sechdrs
+ info
->index
.str
;
2610 unsigned int i
, nsrc
, ndst
, strtab_size
= 0;
2612 /* Put symbol section at end of init part of module. */
2613 symsect
->sh_flags
|= SHF_ALLOC
;
2614 symsect
->sh_entsize
= get_offset(mod
, &mod
->init_layout
.size
, symsect
,
2615 info
->index
.sym
) | INIT_OFFSET_MASK
;
2616 pr_debug("\t%s\n", info
->secstrings
+ symsect
->sh_name
);
2618 src
= (void *)info
->hdr
+ symsect
->sh_offset
;
2619 nsrc
= symsect
->sh_size
/ sizeof(*src
);
2621 /* Compute total space required for the core symbols' strtab. */
2622 for (ndst
= i
= 0; i
< nsrc
; i
++) {
2623 if (i
== 0 || is_livepatch_module(mod
) ||
2624 is_core_symbol(src
+i
, info
->sechdrs
, info
->hdr
->e_shnum
,
2625 info
->index
.pcpu
)) {
2626 strtab_size
+= strlen(&info
->strtab
[src
[i
].st_name
])+1;
2631 /* Append room for core symbols at end of core part. */
2632 info
->symoffs
= ALIGN(mod
->core_layout
.size
, symsect
->sh_addralign
?: 1);
2633 info
->stroffs
= mod
->core_layout
.size
= info
->symoffs
+ ndst
* sizeof(Elf_Sym
);
2634 mod
->core_layout
.size
+= strtab_size
;
2635 mod
->core_layout
.size
= debug_align(mod
->core_layout
.size
);
2637 /* Put string table section at end of init part of module. */
2638 strsect
->sh_flags
|= SHF_ALLOC
;
2639 strsect
->sh_entsize
= get_offset(mod
, &mod
->init_layout
.size
, strsect
,
2640 info
->index
.str
) | INIT_OFFSET_MASK
;
2641 pr_debug("\t%s\n", info
->secstrings
+ strsect
->sh_name
);
2643 /* We'll tack temporary mod_kallsyms on the end. */
2644 mod
->init_layout
.size
= ALIGN(mod
->init_layout
.size
,
2645 __alignof__(struct mod_kallsyms
));
2646 info
->mod_kallsyms_init_off
= mod
->init_layout
.size
;
2647 mod
->init_layout
.size
+= sizeof(struct mod_kallsyms
);
2648 mod
->init_layout
.size
= debug_align(mod
->init_layout
.size
);
2652 * We use the full symtab and strtab which layout_symtab arranged to
2653 * be appended to the init section. Later we switch to the cut-down
2656 static void add_kallsyms(struct module
*mod
, const struct load_info
*info
)
2658 unsigned int i
, ndst
;
2662 Elf_Shdr
*symsec
= &info
->sechdrs
[info
->index
.sym
];
2664 /* Set up to point into init section. */
2665 mod
->kallsyms
= mod
->init_layout
.base
+ info
->mod_kallsyms_init_off
;
2667 mod
->kallsyms
->symtab
= (void *)symsec
->sh_addr
;
2668 mod
->kallsyms
->num_symtab
= symsec
->sh_size
/ sizeof(Elf_Sym
);
2669 /* Make sure we get permanent strtab: don't use info->strtab. */
2670 mod
->kallsyms
->strtab
= (void *)info
->sechdrs
[info
->index
.str
].sh_addr
;
2672 /* Set types up while we still have access to sections. */
2673 for (i
= 0; i
< mod
->kallsyms
->num_symtab
; i
++)
2674 mod
->kallsyms
->symtab
[i
].st_info
2675 = elf_type(&mod
->kallsyms
->symtab
[i
], info
);
2677 /* Now populate the cut down core kallsyms for after init. */
2678 mod
->core_kallsyms
.symtab
= dst
= mod
->core_layout
.base
+ info
->symoffs
;
2679 mod
->core_kallsyms
.strtab
= s
= mod
->core_layout
.base
+ info
->stroffs
;
2680 src
= mod
->kallsyms
->symtab
;
2681 for (ndst
= i
= 0; i
< mod
->kallsyms
->num_symtab
; i
++) {
2682 if (i
== 0 || is_livepatch_module(mod
) ||
2683 is_core_symbol(src
+i
, info
->sechdrs
, info
->hdr
->e_shnum
,
2684 info
->index
.pcpu
)) {
2686 dst
[ndst
++].st_name
= s
- mod
->core_kallsyms
.strtab
;
2687 s
+= strlcpy(s
, &mod
->kallsyms
->strtab
[src
[i
].st_name
],
2691 mod
->core_kallsyms
.num_symtab
= ndst
;
2694 static inline void layout_symtab(struct module
*mod
, struct load_info
*info
)
2698 static void add_kallsyms(struct module
*mod
, const struct load_info
*info
)
2701 #endif /* CONFIG_KALLSYMS */
2703 static void dynamic_debug_setup(struct _ddebug
*debug
, unsigned int num
)
2707 #ifdef CONFIG_DYNAMIC_DEBUG
2708 if (ddebug_add_module(debug
, num
, debug
->modname
))
2709 pr_err("dynamic debug error adding module: %s\n",
2714 static void dynamic_debug_remove(struct _ddebug
*debug
)
2717 ddebug_remove_module(debug
->modname
);
2720 void * __weak
module_alloc(unsigned long size
)
2722 return vmalloc_exec(size
);
2725 #ifdef CONFIG_DEBUG_KMEMLEAK
2726 static void kmemleak_load_module(const struct module
*mod
,
2727 const struct load_info
*info
)
2731 /* only scan the sections containing data */
2732 kmemleak_scan_area(mod
, sizeof(struct module
), GFP_KERNEL
);
2734 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2735 /* Scan all writable sections that's not executable */
2736 if (!(info
->sechdrs
[i
].sh_flags
& SHF_ALLOC
) ||
2737 !(info
->sechdrs
[i
].sh_flags
& SHF_WRITE
) ||
2738 (info
->sechdrs
[i
].sh_flags
& SHF_EXECINSTR
))
2741 kmemleak_scan_area((void *)info
->sechdrs
[i
].sh_addr
,
2742 info
->sechdrs
[i
].sh_size
, GFP_KERNEL
);
2746 static inline void kmemleak_load_module(const struct module
*mod
,
2747 const struct load_info
*info
)
2752 #ifdef CONFIG_MODULE_SIG
2753 static int module_sig_check(struct load_info
*info
, int flags
)
2756 const unsigned long markerlen
= sizeof(MODULE_SIG_STRING
) - 1;
2757 const void *mod
= info
->hdr
;
2760 * Require flags == 0, as a module with version information
2761 * removed is no longer the module that was signed
2764 info
->len
> markerlen
&&
2765 memcmp(mod
+ info
->len
- markerlen
, MODULE_SIG_STRING
, markerlen
) == 0) {
2766 /* We truncate the module to discard the signature */
2767 info
->len
-= markerlen
;
2768 err
= mod_verify_sig(mod
, &info
->len
);
2772 info
->sig_ok
= true;
2776 /* Not having a signature is only an error if we're strict. */
2777 if (err
== -ENOKEY
&& !sig_enforce
)
2782 #else /* !CONFIG_MODULE_SIG */
2783 static int module_sig_check(struct load_info
*info
, int flags
)
2787 #endif /* !CONFIG_MODULE_SIG */
2789 /* Sanity checks against invalid binaries, wrong arch, weird elf version. */
2790 static int elf_header_check(struct load_info
*info
)
2792 if (info
->len
< sizeof(*(info
->hdr
)))
2795 if (memcmp(info
->hdr
->e_ident
, ELFMAG
, SELFMAG
) != 0
2796 || info
->hdr
->e_type
!= ET_REL
2797 || !elf_check_arch(info
->hdr
)
2798 || info
->hdr
->e_shentsize
!= sizeof(Elf_Shdr
))
2801 if (info
->hdr
->e_shoff
>= info
->len
2802 || (info
->hdr
->e_shnum
* sizeof(Elf_Shdr
) >
2803 info
->len
- info
->hdr
->e_shoff
))
2809 #define COPY_CHUNK_SIZE (16*PAGE_SIZE)
2811 static int copy_chunked_from_user(void *dst
, const void __user
*usrc
, unsigned long len
)
2814 unsigned long n
= min(len
, COPY_CHUNK_SIZE
);
2816 if (copy_from_user(dst
, usrc
, n
) != 0)
2826 #ifdef CONFIG_LIVEPATCH
2827 static int check_modinfo_livepatch(struct module
*mod
, struct load_info
*info
)
2829 if (get_modinfo(info
, "livepatch")) {
2831 add_taint_module(mod
, TAINT_LIVEPATCH
, LOCKDEP_STILL_OK
);
2832 pr_notice_once("%s: tainting kernel with TAINT_LIVEPATCH\n",
2838 #else /* !CONFIG_LIVEPATCH */
2839 static int check_modinfo_livepatch(struct module
*mod
, struct load_info
*info
)
2841 if (get_modinfo(info
, "livepatch")) {
2842 pr_err("%s: module is marked as livepatch module, but livepatch support is disabled",
2849 #endif /* CONFIG_LIVEPATCH */
2851 /* Sets info->hdr and info->len. */
2852 static int copy_module_from_user(const void __user
*umod
, unsigned long len
,
2853 struct load_info
*info
)
2858 if (info
->len
< sizeof(*(info
->hdr
)))
2861 err
= security_kernel_read_file(NULL
, READING_MODULE
);
2865 /* Suck in entire file: we'll want most of it. */
2866 info
->hdr
= __vmalloc(info
->len
,
2867 GFP_KERNEL
| __GFP_HIGHMEM
| __GFP_NOWARN
, PAGE_KERNEL
);
2871 if (copy_chunked_from_user(info
->hdr
, umod
, info
->len
) != 0) {
2879 static void free_copy(struct load_info
*info
)
2884 static int rewrite_section_headers(struct load_info
*info
, int flags
)
2888 /* This should always be true, but let's be sure. */
2889 info
->sechdrs
[0].sh_addr
= 0;
2891 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2892 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
2893 if (shdr
->sh_type
!= SHT_NOBITS
2894 && info
->len
< shdr
->sh_offset
+ shdr
->sh_size
) {
2895 pr_err("Module len %lu truncated\n", info
->len
);
2899 /* Mark all sections sh_addr with their address in the
2901 shdr
->sh_addr
= (size_t)info
->hdr
+ shdr
->sh_offset
;
2903 #ifndef CONFIG_MODULE_UNLOAD
2904 /* Don't load .exit sections */
2905 if (strstarts(info
->secstrings
+shdr
->sh_name
, ".exit"))
2906 shdr
->sh_flags
&= ~(unsigned long)SHF_ALLOC
;
2910 /* Track but don't keep modinfo and version sections. */
2911 if (flags
& MODULE_INIT_IGNORE_MODVERSIONS
)
2912 info
->index
.vers
= 0; /* Pretend no __versions section! */
2914 info
->index
.vers
= find_sec(info
, "__versions");
2915 info
->index
.info
= find_sec(info
, ".modinfo");
2916 info
->sechdrs
[info
->index
.info
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
2917 info
->sechdrs
[info
->index
.vers
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
2922 * Set up our basic convenience variables (pointers to section headers,
2923 * search for module section index etc), and do some basic section
2926 * Return the temporary module pointer (we'll replace it with the final
2927 * one when we move the module sections around).
2929 static struct module
*setup_load_info(struct load_info
*info
, int flags
)
2935 /* Set up the convenience variables */
2936 info
->sechdrs
= (void *)info
->hdr
+ info
->hdr
->e_shoff
;
2937 info
->secstrings
= (void *)info
->hdr
2938 + info
->sechdrs
[info
->hdr
->e_shstrndx
].sh_offset
;
2940 err
= rewrite_section_headers(info
, flags
);
2942 return ERR_PTR(err
);
2944 /* Find internal symbols and strings. */
2945 for (i
= 1; i
< info
->hdr
->e_shnum
; i
++) {
2946 if (info
->sechdrs
[i
].sh_type
== SHT_SYMTAB
) {
2947 info
->index
.sym
= i
;
2948 info
->index
.str
= info
->sechdrs
[i
].sh_link
;
2949 info
->strtab
= (char *)info
->hdr
2950 + info
->sechdrs
[info
->index
.str
].sh_offset
;
2955 info
->index
.mod
= find_sec(info
, ".gnu.linkonce.this_module");
2956 if (!info
->index
.mod
) {
2957 pr_warn("No module found in object\n");
2958 return ERR_PTR(-ENOEXEC
);
2960 /* This is temporary: point mod into copy of data. */
2961 mod
= (void *)info
->sechdrs
[info
->index
.mod
].sh_addr
;
2963 if (info
->index
.sym
== 0) {
2964 pr_warn("%s: module has no symbols (stripped?)\n", mod
->name
);
2965 return ERR_PTR(-ENOEXEC
);
2968 info
->index
.pcpu
= find_pcpusec(info
);
2970 /* Check module struct version now, before we try to use module. */
2971 if (!check_modstruct_version(info
->sechdrs
, info
->index
.vers
, mod
))
2972 return ERR_PTR(-ENOEXEC
);
2977 static int check_modinfo(struct module
*mod
, struct load_info
*info
, int flags
)
2979 const char *modmagic
= get_modinfo(info
, "vermagic");
2982 if (flags
& MODULE_INIT_IGNORE_VERMAGIC
)
2985 /* This is allowed: modprobe --force will invalidate it. */
2987 err
= try_to_force_load(mod
, "bad vermagic");
2990 } else if (!same_magic(modmagic
, vermagic
, info
->index
.vers
)) {
2991 pr_err("%s: version magic '%s' should be '%s'\n",
2992 mod
->name
, modmagic
, vermagic
);
2996 if (!get_modinfo(info
, "intree")) {
2997 if (!test_taint(TAINT_OOT_MODULE
))
2998 pr_warn("%s: loading out-of-tree module taints kernel.\n",
3000 add_taint_module(mod
, TAINT_OOT_MODULE
, LOCKDEP_STILL_OK
);
3003 if (get_modinfo(info
, "staging")) {
3004 add_taint_module(mod
, TAINT_CRAP
, LOCKDEP_STILL_OK
);
3005 pr_warn("%s: module is from the staging directory, the quality "
3006 "is unknown, you have been warned.\n", mod
->name
);
3009 err
= check_modinfo_livepatch(mod
, info
);
3013 /* Set up license info based on the info section */
3014 set_license(mod
, get_modinfo(info
, "license"));
3019 static int find_module_sections(struct module
*mod
, struct load_info
*info
)
3021 mod
->kp
= section_objs(info
, "__param",
3022 sizeof(*mod
->kp
), &mod
->num_kp
);
3023 mod
->syms
= section_objs(info
, "__ksymtab",
3024 sizeof(*mod
->syms
), &mod
->num_syms
);
3025 mod
->crcs
= section_addr(info
, "__kcrctab");
3026 mod
->gpl_syms
= section_objs(info
, "__ksymtab_gpl",
3027 sizeof(*mod
->gpl_syms
),
3028 &mod
->num_gpl_syms
);
3029 mod
->gpl_crcs
= section_addr(info
, "__kcrctab_gpl");
3030 mod
->gpl_future_syms
= section_objs(info
,
3031 "__ksymtab_gpl_future",
3032 sizeof(*mod
->gpl_future_syms
),
3033 &mod
->num_gpl_future_syms
);
3034 mod
->gpl_future_crcs
= section_addr(info
, "__kcrctab_gpl_future");
3036 #ifdef CONFIG_UNUSED_SYMBOLS
3037 mod
->unused_syms
= section_objs(info
, "__ksymtab_unused",
3038 sizeof(*mod
->unused_syms
),
3039 &mod
->num_unused_syms
);
3040 mod
->unused_crcs
= section_addr(info
, "__kcrctab_unused");
3041 mod
->unused_gpl_syms
= section_objs(info
, "__ksymtab_unused_gpl",
3042 sizeof(*mod
->unused_gpl_syms
),
3043 &mod
->num_unused_gpl_syms
);
3044 mod
->unused_gpl_crcs
= section_addr(info
, "__kcrctab_unused_gpl");
3046 #ifdef CONFIG_CONSTRUCTORS
3047 mod
->ctors
= section_objs(info
, ".ctors",
3048 sizeof(*mod
->ctors
), &mod
->num_ctors
);
3050 mod
->ctors
= section_objs(info
, ".init_array",
3051 sizeof(*mod
->ctors
), &mod
->num_ctors
);
3052 else if (find_sec(info
, ".init_array")) {
3054 * This shouldn't happen with same compiler and binutils
3055 * building all parts of the module.
3057 pr_warn("%s: has both .ctors and .init_array.\n",
3063 #ifdef CONFIG_TRACEPOINTS
3064 mod
->tracepoints_ptrs
= section_objs(info
, "__tracepoints_ptrs",
3065 sizeof(*mod
->tracepoints_ptrs
),
3066 &mod
->num_tracepoints
);
3068 #ifdef HAVE_JUMP_LABEL
3069 mod
->jump_entries
= section_objs(info
, "__jump_table",
3070 sizeof(*mod
->jump_entries
),
3071 &mod
->num_jump_entries
);
3073 #ifdef CONFIG_EVENT_TRACING
3074 mod
->trace_events
= section_objs(info
, "_ftrace_events",
3075 sizeof(*mod
->trace_events
),
3076 &mod
->num_trace_events
);
3077 mod
->trace_enums
= section_objs(info
, "_ftrace_enum_map",
3078 sizeof(*mod
->trace_enums
),
3079 &mod
->num_trace_enums
);
3081 #ifdef CONFIG_TRACING
3082 mod
->trace_bprintk_fmt_start
= section_objs(info
, "__trace_printk_fmt",
3083 sizeof(*mod
->trace_bprintk_fmt_start
),
3084 &mod
->num_trace_bprintk_fmt
);
3086 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
3087 /* sechdrs[0].sh_size is always zero */
3088 mod
->ftrace_callsites
= section_objs(info
, "__mcount_loc",
3089 sizeof(*mod
->ftrace_callsites
),
3090 &mod
->num_ftrace_callsites
);
3093 mod
->extable
= section_objs(info
, "__ex_table",
3094 sizeof(*mod
->extable
), &mod
->num_exentries
);
3096 if (section_addr(info
, "__obsparm"))
3097 pr_warn("%s: Ignoring obsolete parameters\n", mod
->name
);
3099 info
->debug
= section_objs(info
, "__verbose",
3100 sizeof(*info
->debug
), &info
->num_debug
);
3105 static int move_module(struct module
*mod
, struct load_info
*info
)
3110 /* Do the allocs. */
3111 ptr
= module_alloc(mod
->core_layout
.size
);
3113 * The pointer to this block is stored in the module structure
3114 * which is inside the block. Just mark it as not being a
3117 kmemleak_not_leak(ptr
);
3121 memset(ptr
, 0, mod
->core_layout
.size
);
3122 mod
->core_layout
.base
= ptr
;
3124 if (mod
->init_layout
.size
) {
3125 ptr
= module_alloc(mod
->init_layout
.size
);
3127 * The pointer to this block is stored in the module structure
3128 * which is inside the block. This block doesn't need to be
3129 * scanned as it contains data and code that will be freed
3130 * after the module is initialized.
3132 kmemleak_ignore(ptr
);
3134 module_memfree(mod
->core_layout
.base
);
3137 memset(ptr
, 0, mod
->init_layout
.size
);
3138 mod
->init_layout
.base
= ptr
;
3140 mod
->init_layout
.base
= NULL
;
3142 /* Transfer each section which specifies SHF_ALLOC */
3143 pr_debug("final section addresses:\n");
3144 for (i
= 0; i
< info
->hdr
->e_shnum
; i
++) {
3146 Elf_Shdr
*shdr
= &info
->sechdrs
[i
];
3148 if (!(shdr
->sh_flags
& SHF_ALLOC
))
3151 if (shdr
->sh_entsize
& INIT_OFFSET_MASK
)
3152 dest
= mod
->init_layout
.base
3153 + (shdr
->sh_entsize
& ~INIT_OFFSET_MASK
);
3155 dest
= mod
->core_layout
.base
+ shdr
->sh_entsize
;
3157 if (shdr
->sh_type
!= SHT_NOBITS
)
3158 memcpy(dest
, (void *)shdr
->sh_addr
, shdr
->sh_size
);
3159 /* Update sh_addr to point to copy in image. */
3160 shdr
->sh_addr
= (unsigned long)dest
;
3161 pr_debug("\t0x%lx %s\n",
3162 (long)shdr
->sh_addr
, info
->secstrings
+ shdr
->sh_name
);
3168 static int check_module_license_and_versions(struct module
*mod
)
3170 int prev_taint
= test_taint(TAINT_PROPRIETARY_MODULE
);
3173 * ndiswrapper is under GPL by itself, but loads proprietary modules.
3174 * Don't use add_taint_module(), as it would prevent ndiswrapper from
3175 * using GPL-only symbols it needs.
3177 if (strcmp(mod
->name
, "ndiswrapper") == 0)
3178 add_taint(TAINT_PROPRIETARY_MODULE
, LOCKDEP_NOW_UNRELIABLE
);
3180 /* driverloader was caught wrongly pretending to be under GPL */
3181 if (strcmp(mod
->name
, "driverloader") == 0)
3182 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
3183 LOCKDEP_NOW_UNRELIABLE
);
3185 /* lve claims to be GPL but upstream won't provide source */
3186 if (strcmp(mod
->name
, "lve") == 0)
3187 add_taint_module(mod
, TAINT_PROPRIETARY_MODULE
,
3188 LOCKDEP_NOW_UNRELIABLE
);
3190 if (!prev_taint
&& test_taint(TAINT_PROPRIETARY_MODULE
))
3191 pr_warn("%s: module license taints kernel.\n", mod
->name
);
3193 #ifdef CONFIG_MODVERSIONS
3194 if ((mod
->num_syms
&& !mod
->crcs
)
3195 || (mod
->num_gpl_syms
&& !mod
->gpl_crcs
)
3196 || (mod
->num_gpl_future_syms
&& !mod
->gpl_future_crcs
)
3197 #ifdef CONFIG_UNUSED_SYMBOLS
3198 || (mod
->num_unused_syms
&& !mod
->unused_crcs
)
3199 || (mod
->num_unused_gpl_syms
&& !mod
->unused_gpl_crcs
)
3202 return try_to_force_load(mod
,
3203 "no versions for exported symbols");
3209 static void flush_module_icache(const struct module
*mod
)
3211 mm_segment_t old_fs
;
3213 /* flush the icache in correct context */
3218 * Flush the instruction cache, since we've played with text.
3219 * Do it before processing of module parameters, so the module
3220 * can provide parameter accessor functions of its own.
3222 if (mod
->init_layout
.base
)
3223 flush_icache_range((unsigned long)mod
->init_layout
.base
,
3224 (unsigned long)mod
->init_layout
.base
3225 + mod
->init_layout
.size
);
3226 flush_icache_range((unsigned long)mod
->core_layout
.base
,
3227 (unsigned long)mod
->core_layout
.base
+ mod
->core_layout
.size
);
3232 int __weak
module_frob_arch_sections(Elf_Ehdr
*hdr
,
3240 /* module_blacklist is a comma-separated list of module names */
3241 static char *module_blacklist
;
3242 static bool blacklisted(char *module_name
)
3247 if (!module_blacklist
)
3250 for (p
= module_blacklist
; *p
; p
+= len
) {
3251 len
= strcspn(p
, ",");
3252 if (strlen(module_name
) == len
&& !memcmp(module_name
, p
, len
))
3259 core_param(module_blacklist
, module_blacklist
, charp
, 0400);
3261 static struct module
*layout_and_allocate(struct load_info
*info
, int flags
)
3263 /* Module within temporary copy. */
3268 mod
= setup_load_info(info
, flags
);
3272 if (blacklisted(mod
->name
))
3273 return ERR_PTR(-EPERM
);
3275 err
= check_modinfo(mod
, info
, flags
);
3277 return ERR_PTR(err
);
3279 /* Allow arches to frob section contents and sizes. */
3280 err
= module_frob_arch_sections(info
->hdr
, info
->sechdrs
,
3281 info
->secstrings
, mod
);
3283 return ERR_PTR(err
);
3285 /* We will do a special allocation for per-cpu sections later. */
3286 info
->sechdrs
[info
->index
.pcpu
].sh_flags
&= ~(unsigned long)SHF_ALLOC
;
3289 * Mark ro_after_init section with SHF_RO_AFTER_INIT so that
3290 * layout_sections() can put it in the right place.
3291 * Note: ro_after_init sections also have SHF_{WRITE,ALLOC} set.
3293 ndx
= find_sec(info
, ".data..ro_after_init");
3295 info
->sechdrs
[ndx
].sh_flags
|= SHF_RO_AFTER_INIT
;
3297 /* Determine total sizes, and put offsets in sh_entsize. For now
3298 this is done generically; there doesn't appear to be any
3299 special cases for the architectures. */
3300 layout_sections(mod
, info
);
3301 layout_symtab(mod
, info
);
3303 /* Allocate and move to the final place */
3304 err
= move_module(mod
, info
);
3306 return ERR_PTR(err
);
3308 /* Module has been copied to its final place now: return it. */
3309 mod
= (void *)info
->sechdrs
[info
->index
.mod
].sh_addr
;
3310 kmemleak_load_module(mod
, info
);
3314 /* mod is no longer valid after this! */
3315 static void module_deallocate(struct module
*mod
, struct load_info
*info
)
3317 percpu_modfree(mod
);
3318 module_arch_freeing_init(mod
);
3319 module_memfree(mod
->init_layout
.base
);
3320 module_memfree(mod
->core_layout
.base
);
3323 int __weak
module_finalize(const Elf_Ehdr
*hdr
,
3324 const Elf_Shdr
*sechdrs
,
3330 static int post_relocation(struct module
*mod
, const struct load_info
*info
)
3332 /* Sort exception table now relocations are done. */
3333 sort_extable(mod
->extable
, mod
->extable
+ mod
->num_exentries
);
3335 /* Copy relocated percpu area over. */
3336 percpu_modcopy(mod
, (void *)info
->sechdrs
[info
->index
.pcpu
].sh_addr
,
3337 info
->sechdrs
[info
->index
.pcpu
].sh_size
);
3339 /* Setup kallsyms-specific fields. */
3340 add_kallsyms(mod
, info
);
3342 /* Arch-specific module finalizing. */
3343 return module_finalize(info
->hdr
, info
->sechdrs
, mod
);
3346 /* Is this module of this name done loading? No locks held. */
3347 static bool finished_loading(const char *name
)
3353 * The module_mutex should not be a heavily contended lock;
3354 * if we get the occasional sleep here, we'll go an extra iteration
3355 * in the wait_event_interruptible(), which is harmless.
3357 sched_annotate_sleep();
3358 mutex_lock(&module_mutex
);
3359 mod
= find_module_all(name
, strlen(name
), true);
3360 ret
= !mod
|| mod
->state
== MODULE_STATE_LIVE
3361 || mod
->state
== MODULE_STATE_GOING
;
3362 mutex_unlock(&module_mutex
);
3367 /* Call module constructors. */
3368 static void do_mod_ctors(struct module
*mod
)
3370 #ifdef CONFIG_CONSTRUCTORS
3373 for (i
= 0; i
< mod
->num_ctors
; i
++)
3378 /* For freeing module_init on success, in case kallsyms traversing */
3379 struct mod_initfree
{
3380 struct rcu_head rcu
;
3384 static void do_free_init(struct rcu_head
*head
)
3386 struct mod_initfree
*m
= container_of(head
, struct mod_initfree
, rcu
);
3387 module_memfree(m
->module_init
);
3392 * This is where the real work happens.
3394 * Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb
3395 * helper command 'lx-symbols'.
3397 static noinline
int do_init_module(struct module
*mod
)
3400 struct mod_initfree
*freeinit
;
3402 freeinit
= kmalloc(sizeof(*freeinit
), GFP_KERNEL
);
3407 freeinit
->module_init
= mod
->init_layout
.base
;
3410 * We want to find out whether @mod uses async during init. Clear
3411 * PF_USED_ASYNC. async_schedule*() will set it.
3413 current
->flags
&= ~PF_USED_ASYNC
;
3416 /* Start the module */
3417 if (mod
->init
!= NULL
)
3418 ret
= do_one_initcall(mod
->init
);
3420 goto fail_free_freeinit
;
3423 pr_warn("%s: '%s'->init suspiciously returned %d, it should "
3424 "follow 0/-E convention\n"
3425 "%s: loading module anyway...\n",
3426 __func__
, mod
->name
, ret
, __func__
);
3430 /* Now it's a first class citizen! */
3431 mod
->state
= MODULE_STATE_LIVE
;
3432 blocking_notifier_call_chain(&module_notify_list
,
3433 MODULE_STATE_LIVE
, mod
);
3436 * We need to finish all async code before the module init sequence
3437 * is done. This has potential to deadlock. For example, a newly
3438 * detected block device can trigger request_module() of the
3439 * default iosched from async probing task. Once userland helper
3440 * reaches here, async_synchronize_full() will wait on the async
3441 * task waiting on request_module() and deadlock.
3443 * This deadlock is avoided by perfomring async_synchronize_full()
3444 * iff module init queued any async jobs. This isn't a full
3445 * solution as it will deadlock the same if module loading from
3446 * async jobs nests more than once; however, due to the various
3447 * constraints, this hack seems to be the best option for now.
3448 * Please refer to the following thread for details.
3450 * http://thread.gmane.org/gmane.linux.kernel/1420814
3452 if (!mod
->async_probe_requested
&& (current
->flags
& PF_USED_ASYNC
))
3453 async_synchronize_full();
3455 mutex_lock(&module_mutex
);
3456 /* Drop initial reference. */
3458 trim_init_extable(mod
);
3459 #ifdef CONFIG_KALLSYMS
3460 /* Switch to core kallsyms now init is done: kallsyms may be walking! */
3461 rcu_assign_pointer(mod
->kallsyms
, &mod
->core_kallsyms
);
3463 module_enable_ro(mod
, true);
3464 mod_tree_remove_init(mod
);
3465 disable_ro_nx(&mod
->init_layout
);
3466 module_arch_freeing_init(mod
);
3467 mod
->init_layout
.base
= NULL
;
3468 mod
->init_layout
.size
= 0;
3469 mod
->init_layout
.ro_size
= 0;
3470 mod
->init_layout
.ro_after_init_size
= 0;
3471 mod
->init_layout
.text_size
= 0;
3473 * We want to free module_init, but be aware that kallsyms may be
3474 * walking this with preempt disabled. In all the failure paths, we
3475 * call synchronize_sched(), but we don't want to slow down the success
3476 * path, so use actual RCU here.
3478 call_rcu_sched(&freeinit
->rcu
, do_free_init
);
3479 mutex_unlock(&module_mutex
);
3480 wake_up_all(&module_wq
);
3487 /* Try to protect us from buggy refcounters. */
3488 mod
->state
= MODULE_STATE_GOING
;
3489 synchronize_sched();
3491 blocking_notifier_call_chain(&module_notify_list
,
3492 MODULE_STATE_GOING
, mod
);
3493 klp_module_going(mod
);
3494 ftrace_release_mod(mod
);
3496 wake_up_all(&module_wq
);
3500 static int may_init_module(void)
3502 if (!capable(CAP_SYS_MODULE
) || modules_disabled
)
3509 * We try to place it in the list now to make sure it's unique before
3510 * we dedicate too many resources. In particular, temporary percpu
3511 * memory exhaustion.
3513 static int add_unformed_module(struct module
*mod
)
3518 mod
->state
= MODULE_STATE_UNFORMED
;
3521 mutex_lock(&module_mutex
);
3522 old
= find_module_all(mod
->name
, strlen(mod
->name
), true);
3524 if (old
->state
== MODULE_STATE_COMING
3525 || old
->state
== MODULE_STATE_UNFORMED
) {
3526 /* Wait in case it fails to load. */
3527 mutex_unlock(&module_mutex
);
3528 err
= wait_event_interruptible(module_wq
,
3529 finished_loading(mod
->name
));
3537 mod_update_bounds(mod
);
3538 list_add_rcu(&mod
->list
, &modules
);
3539 mod_tree_insert(mod
);
3543 mutex_unlock(&module_mutex
);
3548 static int complete_formation(struct module
*mod
, struct load_info
*info
)
3552 mutex_lock(&module_mutex
);
3554 /* Find duplicate symbols (must be called under lock). */
3555 err
= verify_export_symbols(mod
);
3559 /* This relies on module_mutex for list integrity. */
3560 module_bug_finalize(info
->hdr
, info
->sechdrs
, mod
);
3562 module_enable_ro(mod
, false);
3563 module_enable_nx(mod
);
3565 /* Mark state as coming so strong_try_module_get() ignores us,
3566 * but kallsyms etc. can see us. */
3567 mod
->state
= MODULE_STATE_COMING
;
3568 mutex_unlock(&module_mutex
);
3573 mutex_unlock(&module_mutex
);
3577 static int prepare_coming_module(struct module
*mod
)
3581 ftrace_module_enable(mod
);
3582 err
= klp_module_coming(mod
);
3586 blocking_notifier_call_chain(&module_notify_list
,
3587 MODULE_STATE_COMING
, mod
);
3591 static int unknown_module_param_cb(char *param
, char *val
, const char *modname
,
3594 struct module
*mod
= arg
;
3597 if (strcmp(param
, "async_probe") == 0) {
3598 mod
->async_probe_requested
= true;
3602 /* Check for magic 'dyndbg' arg */
3603 ret
= ddebug_dyndbg_module_param_cb(param
, val
, modname
);
3605 pr_warn("%s: unknown parameter '%s' ignored\n", modname
, param
);
3609 /* Allocate and load the module: note that size of section 0 is always
3610 zero, and we rely on this for optional sections. */
3611 static int load_module(struct load_info
*info
, const char __user
*uargs
,
3618 err
= module_sig_check(info
, flags
);
3622 err
= elf_header_check(info
);
3626 /* Figure out module layout, and allocate all the memory. */
3627 mod
= layout_and_allocate(info
, flags
);
3633 audit_log_kern_module(mod
->name
);
3635 /* Reserve our place in the list. */
3636 err
= add_unformed_module(mod
);
3640 #ifdef CONFIG_MODULE_SIG
3641 mod
->sig_ok
= info
->sig_ok
;
3643 pr_notice_once("%s: module verification failed: signature "
3644 "and/or required key missing - tainting "
3645 "kernel\n", mod
->name
);
3646 add_taint_module(mod
, TAINT_UNSIGNED_MODULE
, LOCKDEP_STILL_OK
);
3650 /* To avoid stressing percpu allocator, do this once we're unique. */
3651 err
= percpu_modalloc(mod
, info
);
3655 /* Now module is in final location, initialize linked lists, etc. */
3656 err
= module_unload_init(mod
);
3660 init_param_lock(mod
);
3662 /* Now we've got everything in the final locations, we can
3663 * find optional sections. */
3664 err
= find_module_sections(mod
, info
);
3668 err
= check_module_license_and_versions(mod
);
3672 /* Set up MODINFO_ATTR fields */
3673 setup_modinfo(mod
, info
);
3675 /* Fix up syms, so that st_value is a pointer to location. */
3676 err
= simplify_symbols(mod
, info
);
3680 err
= apply_relocations(mod
, info
);
3684 err
= post_relocation(mod
, info
);
3688 flush_module_icache(mod
);
3690 /* Now copy in args */
3691 mod
->args
= strndup_user(uargs
, ~0UL >> 1);
3692 if (IS_ERR(mod
->args
)) {
3693 err
= PTR_ERR(mod
->args
);
3694 goto free_arch_cleanup
;
3697 dynamic_debug_setup(info
->debug
, info
->num_debug
);
3699 /* Ftrace init must be called in the MODULE_STATE_UNFORMED state */
3700 ftrace_module_init(mod
);
3702 /* Finally it's fully formed, ready to start executing. */
3703 err
= complete_formation(mod
, info
);
3705 goto ddebug_cleanup
;
3707 err
= prepare_coming_module(mod
);
3711 /* Module is ready to execute: parsing args may do that. */
3712 after_dashes
= parse_args(mod
->name
, mod
->args
, mod
->kp
, mod
->num_kp
,
3714 unknown_module_param_cb
);
3715 if (IS_ERR(after_dashes
)) {
3716 err
= PTR_ERR(after_dashes
);
3717 goto coming_cleanup
;
3718 } else if (after_dashes
) {
3719 pr_warn("%s: parameters '%s' after `--' ignored\n",
3720 mod
->name
, after_dashes
);
3723 /* Link in to sysfs. */
3724 err
= mod_sysfs_setup(mod
, info
, mod
->kp
, mod
->num_kp
);
3726 goto coming_cleanup
;
3728 if (is_livepatch_module(mod
)) {
3729 err
= copy_module_elf(mod
, info
);
3734 /* Get rid of temporary copy. */
3738 trace_module_load(mod
);
3740 return do_init_module(mod
);
3743 mod_sysfs_teardown(mod
);
3745 mod
->state
= MODULE_STATE_GOING
;
3746 destroy_params(mod
->kp
, mod
->num_kp
);
3747 blocking_notifier_call_chain(&module_notify_list
,
3748 MODULE_STATE_GOING
, mod
);
3749 klp_module_going(mod
);
3751 /* module_bug_cleanup needs module_mutex protection */
3752 mutex_lock(&module_mutex
);
3753 module_bug_cleanup(mod
);
3754 mutex_unlock(&module_mutex
);
3756 /* we can't deallocate the module until we clear memory protection */
3757 module_disable_ro(mod
);
3758 module_disable_nx(mod
);
3761 dynamic_debug_remove(info
->debug
);
3762 synchronize_sched();
3765 module_arch_cleanup(mod
);
3769 module_unload_free(mod
);
3771 mutex_lock(&module_mutex
);
3772 /* Unlink carefully: kallsyms could be walking list. */
3773 list_del_rcu(&mod
->list
);
3774 mod_tree_remove(mod
);
3775 wake_up_all(&module_wq
);
3776 /* Wait for RCU-sched synchronizing before releasing mod->list. */
3777 synchronize_sched();
3778 mutex_unlock(&module_mutex
);
3781 * Ftrace needs to clean up what it initialized.
3782 * This does nothing if ftrace_module_init() wasn't called,
3783 * but it must be called outside of module_mutex.
3785 ftrace_release_mod(mod
);
3786 /* Free lock-classes; relies on the preceding sync_rcu() */
3787 lockdep_free_key_range(mod
->core_layout
.base
, mod
->core_layout
.size
);
3789 module_deallocate(mod
, info
);
3795 SYSCALL_DEFINE3(init_module
, void __user
*, umod
,
3796 unsigned long, len
, const char __user
*, uargs
)
3799 struct load_info info
= { };
3801 err
= may_init_module();
3805 pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
3808 err
= copy_module_from_user(umod
, len
, &info
);
3812 return load_module(&info
, uargs
, 0);
3815 SYSCALL_DEFINE3(finit_module
, int, fd
, const char __user
*, uargs
, int, flags
)
3817 struct load_info info
= { };
3822 err
= may_init_module();
3826 pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd
, uargs
, flags
);
3828 if (flags
& ~(MODULE_INIT_IGNORE_MODVERSIONS
3829 |MODULE_INIT_IGNORE_VERMAGIC
))
3832 err
= kernel_read_file_from_fd(fd
, &hdr
, &size
, INT_MAX
,
3839 return load_module(&info
, uargs
, flags
);
3842 static inline int within(unsigned long addr
, void *start
, unsigned long size
)
3844 return ((void *)addr
>= start
&& (void *)addr
< start
+ size
);
3847 #ifdef CONFIG_KALLSYMS
3849 * This ignores the intensely annoying "mapping symbols" found
3850 * in ARM ELF files: $a, $t and $d.
3852 static inline int is_arm_mapping_symbol(const char *str
)
3854 if (str
[0] == '.' && str
[1] == 'L')
3856 return str
[0] == '$' && strchr("axtd", str
[1])
3857 && (str
[2] == '\0' || str
[2] == '.');
3860 static const char *symname(struct mod_kallsyms
*kallsyms
, unsigned int symnum
)
3862 return kallsyms
->strtab
+ kallsyms
->symtab
[symnum
].st_name
;
3865 static const char *get_ksymbol(struct module
*mod
,
3867 unsigned long *size
,
3868 unsigned long *offset
)
3870 unsigned int i
, best
= 0;
3871 unsigned long nextval
;
3872 struct mod_kallsyms
*kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
3874 /* At worse, next value is at end of module */
3875 if (within_module_init(addr
, mod
))
3876 nextval
= (unsigned long)mod
->init_layout
.base
+mod
->init_layout
.text_size
;
3878 nextval
= (unsigned long)mod
->core_layout
.base
+mod
->core_layout
.text_size
;
3880 /* Scan for closest preceding symbol, and next symbol. (ELF
3881 starts real symbols at 1). */
3882 for (i
= 1; i
< kallsyms
->num_symtab
; i
++) {
3883 if (kallsyms
->symtab
[i
].st_shndx
== SHN_UNDEF
)
3886 /* We ignore unnamed symbols: they're uninformative
3887 * and inserted at a whim. */
3888 if (*symname(kallsyms
, i
) == '\0'
3889 || is_arm_mapping_symbol(symname(kallsyms
, i
)))
3892 if (kallsyms
->symtab
[i
].st_value
<= addr
3893 && kallsyms
->symtab
[i
].st_value
> kallsyms
->symtab
[best
].st_value
)
3895 if (kallsyms
->symtab
[i
].st_value
> addr
3896 && kallsyms
->symtab
[i
].st_value
< nextval
)
3897 nextval
= kallsyms
->symtab
[i
].st_value
;
3904 *size
= nextval
- kallsyms
->symtab
[best
].st_value
;
3906 *offset
= addr
- kallsyms
->symtab
[best
].st_value
;
3907 return symname(kallsyms
, best
);
3910 /* For kallsyms to ask for address resolution. NULL means not found. Careful
3911 * not to lock to avoid deadlock on oopses, simply disable preemption. */
3912 const char *module_address_lookup(unsigned long addr
,
3913 unsigned long *size
,
3914 unsigned long *offset
,
3918 const char *ret
= NULL
;
3922 mod
= __module_address(addr
);
3925 *modname
= mod
->name
;
3926 ret
= get_ksymbol(mod
, addr
, size
, offset
);
3928 /* Make a copy in here where it's safe */
3930 strncpy(namebuf
, ret
, KSYM_NAME_LEN
- 1);
3938 int lookup_module_symbol_name(unsigned long addr
, char *symname
)
3943 list_for_each_entry_rcu(mod
, &modules
, list
) {
3944 if (mod
->state
== MODULE_STATE_UNFORMED
)
3946 if (within_module(addr
, mod
)) {
3949 sym
= get_ksymbol(mod
, addr
, NULL
, NULL
);
3952 strlcpy(symname
, sym
, KSYM_NAME_LEN
);
3962 int lookup_module_symbol_attrs(unsigned long addr
, unsigned long *size
,
3963 unsigned long *offset
, char *modname
, char *name
)
3968 list_for_each_entry_rcu(mod
, &modules
, list
) {
3969 if (mod
->state
== MODULE_STATE_UNFORMED
)
3971 if (within_module(addr
, mod
)) {
3974 sym
= get_ksymbol(mod
, addr
, size
, offset
);
3978 strlcpy(modname
, mod
->name
, MODULE_NAME_LEN
);
3980 strlcpy(name
, sym
, KSYM_NAME_LEN
);
3990 int module_get_kallsym(unsigned int symnum
, unsigned long *value
, char *type
,
3991 char *name
, char *module_name
, int *exported
)
3996 list_for_each_entry_rcu(mod
, &modules
, list
) {
3997 struct mod_kallsyms
*kallsyms
;
3999 if (mod
->state
== MODULE_STATE_UNFORMED
)
4001 kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
4002 if (symnum
< kallsyms
->num_symtab
) {
4003 *value
= kallsyms
->symtab
[symnum
].st_value
;
4004 *type
= kallsyms
->symtab
[symnum
].st_info
;
4005 strlcpy(name
, symname(kallsyms
, symnum
), KSYM_NAME_LEN
);
4006 strlcpy(module_name
, mod
->name
, MODULE_NAME_LEN
);
4007 *exported
= is_exported(name
, *value
, mod
);
4011 symnum
-= kallsyms
->num_symtab
;
4017 static unsigned long mod_find_symname(struct module
*mod
, const char *name
)
4020 struct mod_kallsyms
*kallsyms
= rcu_dereference_sched(mod
->kallsyms
);
4022 for (i
= 0; i
< kallsyms
->num_symtab
; i
++)
4023 if (strcmp(name
, symname(kallsyms
, i
)) == 0 &&
4024 kallsyms
->symtab
[i
].st_info
!= 'U')
4025 return kallsyms
->symtab
[i
].st_value
;
4029 /* Look for this name: can be of form module:name. */
4030 unsigned long module_kallsyms_lookup_name(const char *name
)
4034 unsigned long ret
= 0;
4036 /* Don't lock: we're in enough trouble already. */
4038 if ((colon
= strchr(name
, ':')) != NULL
) {
4039 if ((mod
= find_module_all(name
, colon
- name
, false)) != NULL
)
4040 ret
= mod_find_symname(mod
, colon
+1);
4042 list_for_each_entry_rcu(mod
, &modules
, list
) {
4043 if (mod
->state
== MODULE_STATE_UNFORMED
)
4045 if ((ret
= mod_find_symname(mod
, name
)) != 0)
4053 int module_kallsyms_on_each_symbol(int (*fn
)(void *, const char *,
4054 struct module
*, unsigned long),
4061 module_assert_mutex();
4063 list_for_each_entry(mod
, &modules
, list
) {
4064 /* We hold module_mutex: no need for rcu_dereference_sched */
4065 struct mod_kallsyms
*kallsyms
= mod
->kallsyms
;
4067 if (mod
->state
== MODULE_STATE_UNFORMED
)
4069 for (i
= 0; i
< kallsyms
->num_symtab
; i
++) {
4070 ret
= fn(data
, symname(kallsyms
, i
),
4071 mod
, kallsyms
->symtab
[i
].st_value
);
4078 #endif /* CONFIG_KALLSYMS */
4080 /* Maximum number of characters written by module_flags() */
4081 #define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4)
4083 /* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */
4084 static char *module_flags(struct module
*mod
, char *buf
)
4088 BUG_ON(mod
->state
== MODULE_STATE_UNFORMED
);
4090 mod
->state
== MODULE_STATE_GOING
||
4091 mod
->state
== MODULE_STATE_COMING
) {
4093 bx
+= module_flags_taint(mod
, buf
+ bx
);
4094 /* Show a - for module-is-being-unloaded */
4095 if (mod
->state
== MODULE_STATE_GOING
)
4097 /* Show a + for module-is-being-loaded */
4098 if (mod
->state
== MODULE_STATE_COMING
)
4107 #ifdef CONFIG_PROC_FS
4108 /* Called by the /proc file system to return a list of modules. */
4109 static void *m_start(struct seq_file
*m
, loff_t
*pos
)
4111 mutex_lock(&module_mutex
);
4112 return seq_list_start(&modules
, *pos
);
4115 static void *m_next(struct seq_file
*m
, void *p
, loff_t
*pos
)
4117 return seq_list_next(p
, &modules
, pos
);
4120 static void m_stop(struct seq_file
*m
, void *p
)
4122 mutex_unlock(&module_mutex
);
4125 static int m_show(struct seq_file
*m
, void *p
)
4127 struct module
*mod
= list_entry(p
, struct module
, list
);
4128 char buf
[MODULE_FLAGS_BUF_SIZE
];
4130 /* We always ignore unformed modules. */
4131 if (mod
->state
== MODULE_STATE_UNFORMED
)
4134 seq_printf(m
, "%s %u",
4135 mod
->name
, mod
->init_layout
.size
+ mod
->core_layout
.size
);
4136 print_unload_info(m
, mod
);
4138 /* Informative for users. */
4139 seq_printf(m
, " %s",
4140 mod
->state
== MODULE_STATE_GOING
? "Unloading" :
4141 mod
->state
== MODULE_STATE_COMING
? "Loading" :
4143 /* Used by oprofile and other similar tools. */
4144 seq_printf(m
, " 0x%pK", mod
->core_layout
.base
);
4148 seq_printf(m
, " %s", module_flags(mod
, buf
));
4154 /* Format: modulename size refcount deps address
4156 Where refcount is a number or -, and deps is a comma-separated list
4159 static const struct seq_operations modules_op
= {
4166 static int modules_open(struct inode
*inode
, struct file
*file
)
4168 return seq_open(file
, &modules_op
);
4171 static const struct file_operations proc_modules_operations
= {
4172 .open
= modules_open
,
4174 .llseek
= seq_lseek
,
4175 .release
= seq_release
,
4178 static int __init
proc_modules_init(void)
4180 proc_create("modules", 0, NULL
, &proc_modules_operations
);
4183 module_init(proc_modules_init
);
4186 /* Given an address, look for it in the module exception tables. */
4187 const struct exception_table_entry
*search_module_extables(unsigned long addr
)
4189 const struct exception_table_entry
*e
= NULL
;
4193 mod
= __module_address(addr
);
4197 if (!mod
->num_exentries
)
4200 e
= search_extable(mod
->extable
,
4201 mod
->extable
+ mod
->num_exentries
- 1,
4207 * Now, if we found one, we are running inside it now, hence
4208 * we cannot unload the module, hence no refcnt needed.
4214 * is_module_address - is this address inside a module?
4215 * @addr: the address to check.
4217 * See is_module_text_address() if you simply want to see if the address
4218 * is code (not data).
4220 bool is_module_address(unsigned long addr
)
4225 ret
= __module_address(addr
) != NULL
;
4232 * __module_address - get the module which contains an address.
4233 * @addr: the address.
4235 * Must be called with preempt disabled or module mutex held so that
4236 * module doesn't get freed during this.
4238 struct module
*__module_address(unsigned long addr
)
4242 if (addr
< module_addr_min
|| addr
> module_addr_max
)
4245 module_assert_mutex_or_preempt();
4247 mod
= mod_find(addr
);
4249 BUG_ON(!within_module(addr
, mod
));
4250 if (mod
->state
== MODULE_STATE_UNFORMED
)
4255 EXPORT_SYMBOL_GPL(__module_address
);
4258 * is_module_text_address - is this address inside module code?
4259 * @addr: the address to check.
4261 * See is_module_address() if you simply want to see if the address is
4262 * anywhere in a module. See kernel_text_address() for testing if an
4263 * address corresponds to kernel or module code.
4265 bool is_module_text_address(unsigned long addr
)
4270 ret
= __module_text_address(addr
) != NULL
;
4277 * __module_text_address - get the module whose code contains an address.
4278 * @addr: the address.
4280 * Must be called with preempt disabled or module mutex held so that
4281 * module doesn't get freed during this.
4283 struct module
*__module_text_address(unsigned long addr
)
4285 struct module
*mod
= __module_address(addr
);
4287 /* Make sure it's within the text section. */
4288 if (!within(addr
, mod
->init_layout
.base
, mod
->init_layout
.text_size
)
4289 && !within(addr
, mod
->core_layout
.base
, mod
->core_layout
.text_size
))
4294 EXPORT_SYMBOL_GPL(__module_text_address
);
4296 /* Don't grab lock, we're oopsing. */
4297 void print_modules(void)
4300 char buf
[MODULE_FLAGS_BUF_SIZE
];
4302 printk(KERN_DEFAULT
"Modules linked in:");
4303 /* Most callers should already have preempt disabled, but make sure */
4305 list_for_each_entry_rcu(mod
, &modules
, list
) {
4306 if (mod
->state
== MODULE_STATE_UNFORMED
)
4308 pr_cont(" %s%s", mod
->name
, module_flags(mod
, buf
));
4311 if (last_unloaded_module
[0])
4312 pr_cont(" [last unloaded: %s]", last_unloaded_module
);
4316 #ifdef CONFIG_MODVERSIONS
4317 /* Generate the signature for all relevant module structures here.
4318 * If these change, we don't want to try to parse the module. */
4319 void module_layout(struct module
*mod
,
4320 struct modversion_info
*ver
,
4321 struct kernel_param
*kp
,
4322 struct kernel_symbol
*ks
,
4323 struct tracepoint
* const *tp
)
4326 EXPORT_SYMBOL(module_layout
);