1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * Dynamic loading of modules into the kernel.
4 *
5 * Rewritten by Richard Henderson <rth@tamu.edu> Dec 1996
6 * Rewritten again by Rusty Russell, 2002
7 */
8
9 #ifndef _LINUX_MODULE_H
10 #define _LINUX_MODULE_H
11
12 #include <linux/list.h>
13 #include <linux/stat.h>
14 #include <linux/buildid.h>
15 #include <linux/compiler.h>
16 #include <linux/cache.h>
17 #include <linux/cleanup.h>
18 #include <linux/kmod.h>
19 #include <linux/init.h>
20 #include <linux/elf.h>
21 #include <linux/stringify.h>
22 #include <linux/kobject.h>
23 #include <linux/moduleparam.h>
24 #include <linux/jump_label.h>
25 #include <linux/export.h>
26 #include <linux/rbtree_latch.h>
27 #include <linux/error-injection.h>
28 #include <linux/tracepoint-defs.h>
29 #include <linux/srcu.h>
30 #include <linux/static_call_types.h>
31 #include <linux/dynamic_debug.h>
32
33 #include <linux/percpu.h>
34 #include <asm/module.h>
35
36 #define MODULE_NAME_LEN __MODULE_NAME_LEN
37
38 struct modversion_info {
39 unsigned long crc;
40 char name[MODULE_NAME_LEN];
41 };
42
43 struct module;
44 struct exception_table_entry;
45
46 struct module_kobject {
47 struct kobject kobj;
48 struct module *mod;
49 struct kobject *drivers_dir;
50 struct module_param_attrs *mp;
51 struct completion *kobj_completion;
52 } __randomize_layout;
53
54 struct module_attribute {
55 struct attribute attr;
56 ssize_t (*show)(const struct module_attribute *, struct module_kobject *,
57 char *);
58 ssize_t (*store)(const struct module_attribute *, struct module_kobject *,
59 const char *, size_t count);
60 void (*setup)(struct module *, const char *);
61 int (*test)(struct module *);
62 void (*free)(struct module *);
63 };
64
65 struct module_version_attribute {
66 struct module_attribute mattr;
67 const char *module_name;
68 const char *version;
69 };
70
71 extern ssize_t __modver_version_show(const struct module_attribute *,
72 struct module_kobject *, char *);
73
74 extern const struct module_attribute module_uevent;
75
76 /* These are either module local, or the kernel's dummy ones. */
77 extern int init_module(void);
78 extern void cleanup_module(void);
79
80 #ifndef MODULE
81 /**
82 * module_init() - driver initialization entry point
83 * @x: function to be run at kernel boot time or module insertion
84 *
85 * module_init() will either be called during do_initcalls() (if
86 * builtin) or at module insertion time (if a module). There can only
87 * be one per module.
88 */
89 #define module_init(x) __initcall(x);
90
91 /**
92 * module_exit() - driver exit entry point
93 * @x: function to be run when driver is removed
94 *
95 * module_exit() will wrap the driver clean-up code
96 * with cleanup_module() when used with rmmod when
97 * the driver is a module. If the driver is statically
98 * compiled into the kernel, module_exit() has no effect.
99 * There can only be one per module.
100 */
101 #define module_exit(x) __exitcall(x);
102
103 #else /* MODULE */
104
105 /*
106 * In most cases loadable modules do not need custom
107 * initcall levels. There are still some valid cases where
108 * a driver may be needed early if built in, and does not
109 * matter when built as a loadable module. Like bus
110 * snooping debug drivers.
111 */
112 #define early_initcall(fn) module_init(fn)
113 #define core_initcall(fn) module_init(fn)
114 #define core_initcall_sync(fn) module_init(fn)
115 #define postcore_initcall(fn) module_init(fn)
116 #define postcore_initcall_sync(fn) module_init(fn)
117 #define arch_initcall(fn) module_init(fn)
118 #define subsys_initcall(fn) module_init(fn)
119 #define subsys_initcall_sync(fn) module_init(fn)
120 #define fs_initcall(fn) module_init(fn)
121 #define fs_initcall_sync(fn) module_init(fn)
122 #define rootfs_initcall(fn) module_init(fn)
123 #define device_initcall(fn) module_init(fn)
124 #define device_initcall_sync(fn) module_init(fn)
125 #define late_initcall(fn) module_init(fn)
126 #define late_initcall_sync(fn) module_init(fn)
127
128 #define console_initcall(fn) module_init(fn)
129
130 /* Each module must use one module_init(). */
131 #define module_init(initfn) \
132 static inline initcall_t __maybe_unused __inittest(void) \
133 { return initfn; } \
134 int init_module(void) __copy(initfn) \
135 __attribute__((alias(#initfn))); \
136 ___ADDRESSABLE(init_module, __initdata);
137
138 /* This is only required if you want to be unloadable. */
139 #define module_exit(exitfn) \
140 static inline exitcall_t __maybe_unused __exittest(void) \
141 { return exitfn; } \
142 void cleanup_module(void) __copy(exitfn) \
143 __attribute__((alias(#exitfn))); \
144 ___ADDRESSABLE(cleanup_module, __exitdata);
145
146 #endif
147
148 /* This means "can be init if no module support, otherwise module load
149 may call it." */
150 #ifdef CONFIG_MODULES
151 #define __init_or_module
152 #define __initdata_or_module
153 #define __initconst_or_module
154 #else
155 #define __init_or_module __init
156 #define __initdata_or_module __initdata
157 #define __initconst_or_module __initconst
158 #endif /*CONFIG_MODULES*/
159
160 struct module_kobject *lookup_or_create_module_kobject(const char *name);
161
162 /* For userspace: you can also call me... */
163 #define MODULE_ALIAS(_alias) MODULE_INFO(alias, _alias)
164
165 /* Soft module dependencies. See man modprobe.d for details.
166 * Example: MODULE_SOFTDEP("pre: module-foo module-bar post: module-baz")
167 */
168 #define MODULE_SOFTDEP(_softdep) MODULE_INFO(softdep, _softdep)
169
170 /*
171 * Weak module dependencies. See man modprobe.d for details.
172 * Example: MODULE_WEAKDEP("module-foo")
173 */
174 #define MODULE_WEAKDEP(_weakdep) MODULE_INFO(weakdep, _weakdep)
175
176 /*
177 * MODULE_FILE is used for generating modules.builtin
178 * So, make it no-op when this is being built as a module
179 */
180 #ifdef MODULE
181 #define MODULE_FILE
182 #else
183 #define MODULE_FILE MODULE_INFO(file, KBUILD_MODFILE);
184 #endif
185
186 /*
187 * The following license idents are currently accepted as indicating free
188 * software modules
189 *
190 * "GPL" [GNU Public License v2]
191 * "GPL v2" [GNU Public License v2]
192 * "GPL and additional rights" [GNU Public License v2 rights and more]
193 * "Dual BSD/GPL" [GNU Public License v2
194 * or BSD license choice]
195 * "Dual MIT/GPL" [GNU Public License v2
196 * or MIT license choice]
197 * "Dual MPL/GPL" [GNU Public License v2
198 * or Mozilla license choice]
199 *
200 * The following other idents are available
201 *
202 * "Proprietary" [Non free products]
203 *
204 * Both "GPL v2" and "GPL" (the latter also in dual licensed strings) are
205 * merely stating that the module is licensed under the GPL v2, but are not
206 * telling whether "GPL v2 only" or "GPL v2 or later". The reason why there
207 * are two variants is a historic and failed attempt to convey more
208 * information in the MODULE_LICENSE string. For module loading the
209 * "only/or later" distinction is completely irrelevant and does neither
210 * replace the proper license identifiers in the corresponding source file
211 * nor amends them in any way. The sole purpose is to make the
212 * 'Proprietary' flagging work and to refuse to bind symbols which are
213 * exported with EXPORT_SYMBOL_GPL when a non free module is loaded.
214 *
215 * In the same way "BSD" is not a clear license information. It merely
216 * states, that the module is licensed under one of the compatible BSD
217 * license variants. The detailed and correct license information is again
218 * to be found in the corresponding source files.
219 *
220 * There are dual licensed components, but when running with Linux it is the
221 * GPL that is relevant so this is a non issue. Similarly LGPL linked with GPL
222 * is a GPL combined work.
223 *
224 * This exists for several reasons
225 * 1. So modinfo can show license info for users wanting to vet their setup
226 * is free
227 * 2. So the community can ignore bug reports including proprietary modules
228 * 3. So vendors can do likewise based on their own policies
229 */
230 #define MODULE_LICENSE(_license) MODULE_FILE MODULE_INFO(license, _license)
231
232 /*
233 * Author(s), use "Name <email>" or just "Name", for multiple
234 * authors use multiple MODULE_AUTHOR() statements/lines.
235 */
236 #define MODULE_AUTHOR(_author) MODULE_INFO(author, _author)
237
238 /* What your module does. */
239 #define MODULE_DESCRIPTION(_description) MODULE_INFO(description, _description)
240
241 /*
242 * Format: __mod_device_table__kmod_<modname>__<type>__<name>
243 * Parts of the string `__kmod_` and `__` are used as delimiters when parsing
244 * a symbol in file2alias.c
245 */
246 #define __mod_device_table(type, name) \
247 __PASTE(__mod_device_table__, \
248 __PASTE(kmod_, \
249 __PASTE(__KBUILD_MODNAME, \
250 __PASTE(__, \
251 __PASTE(type, \
252 __PASTE(__, name))))))
253
254 /* Creates an alias so file2alias.c can find device table. */
255 #define MODULE_DEVICE_TABLE(type, name) \
256 static typeof(name) __mod_device_table(type, name) \
257 __attribute__ ((used, alias(__stringify(name))))
258
259 /* Version of form [<epoch>:]<version>[-<extra-version>].
260 * Or for CVS/RCS ID version, everything but the number is stripped.
261 * <epoch>: A (small) unsigned integer which allows you to start versions
262 * anew. If not mentioned, it's zero. eg. "2:1.0" is after
263 * "1:2.0".
264
265 * <version>: The <version> may contain only alphanumerics and the
266 * character `.'. Ordered by numeric sort for numeric parts,
267 * ascii sort for ascii parts (as per RPM or DEB algorithm).
268
269 * <extraversion>: Like <version>, but inserted for local
270 * customizations, eg "rh3" or "rusty1".
271
272 * Using this automatically adds a checksum of the .c files and the
273 * local headers in "srcversion".
274 */
275
276 #if defined(MODULE) || !defined(CONFIG_SYSFS)
277 #define MODULE_VERSION(_version) MODULE_INFO(version, _version)
278 #else
279 #define MODULE_VERSION(_version) \
280 MODULE_INFO(version, _version); \
281 static const struct module_version_attribute __modver_attr \
282 __used __section("__modver") \
283 __aligned(__alignof__(struct module_version_attribute)) \
284 = { \
285 .mattr = { \
286 .attr = { \
287 .name = "version", \
288 .mode = S_IRUGO, \
289 }, \
290 .show = __modver_version_show, \
291 }, \
292 .module_name = KBUILD_MODNAME, \
293 .version = _version, \
294 }
295 #endif
296
297 /* Optional firmware file (or files) needed by the module
298 * format is simply firmware file name. Multiple firmware
299 * files require multiple MODULE_FIRMWARE() specifiers */
300 #define MODULE_FIRMWARE(_firmware) MODULE_INFO(firmware, _firmware)
301
302 #define MODULE_IMPORT_NS(ns) MODULE_INFO(import_ns, ns)
303
304 struct notifier_block;
305
306 enum module_state {
307 MODULE_STATE_LIVE, /* Normal state. */
308 MODULE_STATE_COMING, /* Full formed, running module_init. */
309 MODULE_STATE_GOING, /* Going away. */
310 MODULE_STATE_UNFORMED, /* Still setting it up. */
311 };
312
313 struct mod_tree_node {
314 struct module *mod;
315 struct latch_tree_node node;
316 };
317
318 enum mod_mem_type {
319 MOD_TEXT = 0,
320 MOD_DATA,
321 MOD_RODATA,
322 MOD_RO_AFTER_INIT,
323 MOD_INIT_TEXT,
324 MOD_INIT_DATA,
325 MOD_INIT_RODATA,
326
327 MOD_MEM_NUM_TYPES,
328 MOD_INVALID = -1,
329 };
330
331 #define mod_mem_type_is_init(type) \
332 ((type) == MOD_INIT_TEXT || \
333 (type) == MOD_INIT_DATA || \
334 (type) == MOD_INIT_RODATA)
335
336 #define mod_mem_type_is_core(type) (!mod_mem_type_is_init(type))
337
338 #define mod_mem_type_is_text(type) \
339 ((type) == MOD_TEXT || \
340 (type) == MOD_INIT_TEXT)
341
342 #define mod_mem_type_is_data(type) (!mod_mem_type_is_text(type))
343
344 #define mod_mem_type_is_core_data(type) \
345 (mod_mem_type_is_core(type) && \
346 mod_mem_type_is_data(type))
347
348 #define for_each_mod_mem_type(type) \
349 for (enum mod_mem_type (type) = 0; \
350 (type) < MOD_MEM_NUM_TYPES; (type)++)
351
352 #define for_class_mod_mem_type(type, class) \
353 for_each_mod_mem_type(type) \
354 if (mod_mem_type_is_##class(type))
355
356 struct module_memory {
357 void *base;
358 bool is_rox;
359 unsigned int size;
360
361 #ifdef CONFIG_MODULES_TREE_LOOKUP
362 struct mod_tree_node mtn;
363 #endif
364 };
365
366 #ifdef CONFIG_MODULES_TREE_LOOKUP
367 /* Only touch one cacheline for common rbtree-for-core-layout case. */
368 #define __module_memory_align ____cacheline_aligned
369 #else
370 #define __module_memory_align
371 #endif
372
373 struct mod_kallsyms {
374 Elf_Sym *symtab;
375 unsigned int num_symtab;
376 char *strtab;
377 char *typetab;
378 };
379
380 #ifdef CONFIG_LIVEPATCH
381 /**
382 * struct klp_modinfo - ELF information preserved from the livepatch module
383 *
384 * @hdr: ELF header
385 * @sechdrs: Section header table
386 * @secstrings: String table for the section headers
387 * @symndx: The symbol table section index
388 */
389 struct klp_modinfo {
390 Elf_Ehdr hdr;
391 Elf_Shdr *sechdrs;
392 char *secstrings;
393 unsigned int symndx;
394 };
395 #endif
396
397 struct module {
398 enum module_state state;
399
400 /* Member of list of modules */
401 struct list_head list;
402
403 /* Unique handle for this module */
404 char name[MODULE_NAME_LEN];
405
406 #ifdef CONFIG_STACKTRACE_BUILD_ID
407 /* Module build ID */
408 unsigned char build_id[BUILD_ID_SIZE_MAX];
409 #endif
410
411 /* Sysfs stuff. */
412 struct module_kobject mkobj;
413 struct module_attribute *modinfo_attrs;
414 const char *version;
415 const char *srcversion;
416 const char *imported_namespaces;
417 struct kobject *holders_dir;
418
419 /* Exported symbols */
420 const struct kernel_symbol *syms;
421 const u32 *crcs;
422 const u8 *flagstab;
423 unsigned int num_syms;
424
425 #ifdef CONFIG_ARCH_USES_CFI_TRAPS
426 s32 *kcfi_traps;
427 s32 *kcfi_traps_end;
428 #endif
429
430 /* Kernel parameters. */
431 #ifdef CONFIG_SYSFS
432 struct mutex param_lock;
433 #endif
434 struct kernel_param *kp;
435 unsigned int num_kp;
436
437 /* GPL-only exported symbols. */
438 bool using_gplonly_symbols;
439
440 #ifdef CONFIG_MODULE_SIG
441 /* Signature was verified. */
442 bool sig_ok;
443 #endif
444
445 bool async_probe_requested;
446
447 /* Exception table */
448 unsigned int num_exentries;
449 struct exception_table_entry *extable;
450
451 /* Startup function. */
452 int (*init)(void);
453
454 struct module_memory mem[MOD_MEM_NUM_TYPES] __module_memory_align;
455
456 /* Arch-specific module values */
457 struct mod_arch_specific arch;
458
459 unsigned long taints; /* same bits as kernel:taint_flags */
460
461 #ifdef CONFIG_GENERIC_BUG
462 /* Support for BUG */
463 unsigned num_bugs;
464 struct list_head bug_list;
465 struct bug_entry *bug_table;
466 #endif
467
468 #ifdef CONFIG_KALLSYMS
469 /* Protected by RCU and/or module_mutex: use rcu_dereference() */
470 struct mod_kallsyms __rcu *kallsyms;
471 struct mod_kallsyms core_kallsyms;
472
473 /* Section attributes */
474 struct module_sect_attrs *sect_attrs;
475
476 /* Notes attributes */
477 struct module_notes_attrs *notes_attrs;
478 #endif
479
480 /* The command line arguments (may be mangled). People like
481 keeping pointers to this stuff */
482 char *args;
483
484 #ifdef CONFIG_SMP
485 /* Per-cpu data. */
486 void __percpu *percpu;
487 unsigned int percpu_size;
488 #endif
489 void *noinstr_text_start;
490 unsigned int noinstr_text_size;
491
492 #ifdef CONFIG_TRACEPOINTS
493 unsigned int num_tracepoints;
494 tracepoint_ptr_t *tracepoints_ptrs;
495 #endif
496 #ifdef CONFIG_TREE_SRCU
497 unsigned int num_srcu_structs;
498 struct srcu_struct **srcu_struct_ptrs;
499 #endif
500 #ifdef CONFIG_BPF_EVENTS
501 unsigned int num_bpf_raw_events;
502 struct bpf_raw_event_map *bpf_raw_events;
503 #endif
504 #ifdef CONFIG_DEBUG_INFO_BTF_MODULES
505 unsigned int btf_data_size;
506 unsigned int btf_base_data_size;
507 void *btf_data;
508 void *btf_base_data;
509 #endif
510 #ifdef CONFIG_JUMP_LABEL
511 struct jump_entry *jump_entries;
512 unsigned int num_jump_entries;
513 #endif
514 #ifdef CONFIG_TRACING
515 unsigned int num_trace_bprintk_fmt;
516 const char **trace_bprintk_fmt_start;
517 #endif
518 #ifdef CONFIG_EVENT_TRACING
519 struct trace_event_call **trace_events;
520 unsigned int num_trace_events;
521 struct trace_eval_map **trace_evals;
522 unsigned int num_trace_evals;
523 #endif
524 #ifdef CONFIG_DYNAMIC_FTRACE
525 unsigned int num_ftrace_callsites;
526 unsigned long *ftrace_callsites;
527 #endif
528 #ifdef CONFIG_KPROBES
529 void *kprobes_text_start;
530 unsigned int kprobes_text_size;
531 unsigned long *kprobe_blacklist;
532 unsigned int num_kprobe_blacklist;
533 #endif
534 #ifdef CONFIG_HAVE_STATIC_CALL_INLINE
535 int num_static_call_sites;
536 struct static_call_site *static_call_sites;
537 #endif
538 #if IS_ENABLED(CONFIG_KUNIT)
539 int num_kunit_init_suites;
540 struct kunit_suite **kunit_init_suites;
541 int num_kunit_suites;
542 struct kunit_suite **kunit_suites;
543 #endif
544
545
546 #ifdef CONFIG_LIVEPATCH
547 bool klp; /* Is this a livepatch module? */
548 bool klp_alive;
549
550 /* ELF information */
551 struct klp_modinfo *klp_info;
552 #endif
553
554 #ifdef CONFIG_PRINTK_INDEX
555 unsigned int printk_index_size;
556 struct pi_entry **printk_index_start;
557 #endif
558
559 #ifdef CONFIG_MODULE_UNLOAD
560 /* What modules depend on me? */
561 struct list_head source_list;
562 /* What modules do I depend on? */
563 struct list_head target_list;
564
565 /* Destruction function. */
566 void (*exit)(void);
567
568 atomic_t refcnt;
569 #endif
570
571 #ifdef CONFIG_CONSTRUCTORS
572 /* Constructor functions. */
573 ctor_fn_t *ctors;
574 unsigned int num_ctors;
575 #endif
576
577 #ifdef CONFIG_FUNCTION_ERROR_INJECTION
578 struct error_injection_entry *ei_funcs;
579 unsigned int num_ei_funcs;
580 #endif
581 #ifdef CONFIG_DYNAMIC_DEBUG_CORE
582 struct _ddebug_info dyndbg_info;
583 #endif
584 } ____cacheline_aligned __randomize_layout;
585 #ifndef MODULE_ARCH_INIT
586 #define MODULE_ARCH_INIT {}
587 #endif
588
589 #ifdef CONFIG_MODULES
590
591 /* Get/put a kernel symbol (calls must be symmetric) */
592 void *__symbol_get(const char *symbol);
593 void *__symbol_get_gpl(const char *symbol);
594 #define symbol_get(x) ({ \
595 static const char __notrim[] \
596 __used __section(".no_trim_symbol") = __stringify(x); \
597 (typeof(&x))(__symbol_get(__stringify(x))); })
598
599 #ifndef HAVE_ARCH_KALLSYMS_SYMBOL_VALUE
kallsyms_symbol_value(const Elf_Sym * sym)600 static inline unsigned long kallsyms_symbol_value(const Elf_Sym *sym)
601 {
602 return sym->st_value;
603 }
604 #endif
605
606 /* FIXME: It'd be nice to isolate modules during init, too, so they
607 aren't used before they (may) fail. But presently too much code
608 (IDE & SCSI) require entry into the module during init.*/
module_is_live(struct module * mod)609 static inline bool module_is_live(struct module *mod)
610 {
611 return mod->state != MODULE_STATE_GOING;
612 }
613
module_is_coming(struct module * mod)614 static inline bool module_is_coming(struct module *mod)
615 {
616 return mod->state == MODULE_STATE_COMING;
617 }
618
619 struct module *__module_text_address(unsigned long addr);
620 struct module *__module_address(unsigned long addr);
621 bool is_module_address(unsigned long addr);
622 bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr);
623 bool is_module_percpu_address(unsigned long addr);
624 bool is_module_text_address(unsigned long addr);
625
within_module_mem_type(unsigned long addr,const struct module * mod,enum mod_mem_type type)626 static inline bool within_module_mem_type(unsigned long addr,
627 const struct module *mod,
628 enum mod_mem_type type)
629 {
630 unsigned long base, size;
631
632 base = (unsigned long)mod->mem[type].base;
633 size = mod->mem[type].size;
634 return addr - base < size;
635 }
636
within_module_core(unsigned long addr,const struct module * mod)637 static inline bool within_module_core(unsigned long addr,
638 const struct module *mod)
639 {
640 for_class_mod_mem_type(type, core) {
641 if (within_module_mem_type(addr, mod, type))
642 return true;
643 }
644 return false;
645 }
646
within_module_init(unsigned long addr,const struct module * mod)647 static inline bool within_module_init(unsigned long addr,
648 const struct module *mod)
649 {
650 for_class_mod_mem_type(type, init) {
651 if (within_module_mem_type(addr, mod, type))
652 return true;
653 }
654 return false;
655 }
656
within_module(unsigned long addr,const struct module * mod)657 static inline bool within_module(unsigned long addr, const struct module *mod)
658 {
659 return within_module_init(addr, mod) || within_module_core(addr, mod);
660 }
661
662 /* Search for module by name: must be in a RCU critical section. */
663 struct module *find_module(const char *name);
664
665 extern void __noreturn __module_put_and_kthread_exit(struct module *mod,
666 long code);
667 #define module_put_and_kthread_exit(code) __module_put_and_kthread_exit(THIS_MODULE, code)
668
669 #ifdef CONFIG_MODULE_UNLOAD
670 int module_refcount(struct module *mod);
671 void __symbol_put(const char *symbol);
672 #define symbol_put(x) __symbol_put(__stringify(x))
673 void symbol_put_addr(void *addr);
674
675 /* Sometimes we know we already have a refcount, and it's easier not
676 to handle the error case (which only happens with rmmod --wait). */
677 extern void __module_get(struct module *module);
678
679 /**
680 * try_module_get() - take module refcount unless module is being removed
681 * @module: the module we should check for
682 *
683 * Only try to get a module reference count if the module is not being removed.
684 * This call will fail if the module is in the process of being removed.
685 *
686 * Care must also be taken to ensure the module exists and is alive prior to
687 * usage of this call. This can be gauranteed through two means:
688 *
689 * 1) Direct protection: you know an earlier caller must have increased the
690 * module reference through __module_get(). This can typically be achieved
691 * by having another entity other than the module itself increment the
692 * module reference count.
693 *
694 * 2) Implied protection: there is an implied protection against module
695 * removal. An example of this is the implied protection used by kernfs /
696 * sysfs. The sysfs store / read file operations are guaranteed to exist
697 * through the use of kernfs's active reference (see kernfs_active()) and a
698 * sysfs / kernfs file removal cannot happen unless the same file is not
699 * active. Therefore, if a sysfs file is being read or written to the module
700 * which created it must still exist. It is therefore safe to use
701 * try_module_get() on module sysfs store / read ops.
702 *
703 * One of the real values to try_module_get() is the module_is_live() check
704 * which ensures that the caller of try_module_get() can yield to userspace
705 * module removal requests and gracefully fail if the module is on its way out.
706 *
707 * Returns true if the reference count was successfully incremented.
708 */
709 extern bool try_module_get(struct module *module);
710
711 /**
712 * module_put() - release a reference count to a module
713 * @module: the module we should release a reference count for
714 *
715 * If you successfully bump a reference count to a module with try_module_get(),
716 * when you are finished you must call module_put() to release that reference
717 * count.
718 */
719 extern void module_put(struct module *module);
720
721 #else /*!CONFIG_MODULE_UNLOAD*/
try_module_get(struct module * module)722 static inline bool try_module_get(struct module *module)
723 {
724 return !module || module_is_live(module);
725 }
module_put(struct module * module)726 static inline void module_put(struct module *module)
727 {
728 }
__module_get(struct module * module)729 static inline void __module_get(struct module *module)
730 {
731 }
732 #define symbol_put(x) do { } while (0)
733 #define symbol_put_addr(p) do { } while (0)
734
735 #endif /* CONFIG_MODULE_UNLOAD */
736
737 /* This is a #define so the string doesn't get put in every .o file */
738 #define module_name(mod) \
739 ({ \
740 struct module *__mod = (mod); \
741 __mod ? __mod->name : "kernel"; \
742 })
743
module_buildid(struct module * mod)744 static inline const unsigned char *module_buildid(struct module *mod)
745 {
746 #ifdef CONFIG_STACKTRACE_BUILD_ID
747 return mod->build_id;
748 #else
749 return NULL;
750 #endif
751 }
752
753 /* Dereference module function descriptor */
754 void *dereference_module_function_descriptor(struct module *mod, void *ptr);
755
756 int register_module_notifier(struct notifier_block *nb);
757 int unregister_module_notifier(struct notifier_block *nb);
758
759 extern void print_modules(void);
760
module_requested_async_probing(struct module * module)761 static inline bool module_requested_async_probing(struct module *module)
762 {
763 return module && module->async_probe_requested;
764 }
765
is_livepatch_module(struct module * mod)766 static inline bool is_livepatch_module(struct module *mod)
767 {
768 #ifdef CONFIG_LIVEPATCH
769 return mod->klp;
770 #else
771 return false;
772 #endif
773 }
774
775 void module_for_each_mod(int(*func)(struct module *mod, void *data), void *data);
776
777 #else /* !CONFIG_MODULES... */
778
__module_address(unsigned long addr)779 static inline struct module *__module_address(unsigned long addr)
780 {
781 return NULL;
782 }
783
__module_text_address(unsigned long addr)784 static inline struct module *__module_text_address(unsigned long addr)
785 {
786 return NULL;
787 }
788
is_module_address(unsigned long addr)789 static inline bool is_module_address(unsigned long addr)
790 {
791 return false;
792 }
793
is_module_percpu_address(unsigned long addr)794 static inline bool is_module_percpu_address(unsigned long addr)
795 {
796 return false;
797 }
798
__is_module_percpu_address(unsigned long addr,unsigned long * can_addr)799 static inline bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr)
800 {
801 return false;
802 }
803
is_module_text_address(unsigned long addr)804 static inline bool is_module_text_address(unsigned long addr)
805 {
806 return false;
807 }
808
within_module_core(unsigned long addr,const struct module * mod)809 static inline bool within_module_core(unsigned long addr,
810 const struct module *mod)
811 {
812 return false;
813 }
814
within_module_init(unsigned long addr,const struct module * mod)815 static inline bool within_module_init(unsigned long addr,
816 const struct module *mod)
817 {
818 return false;
819 }
820
within_module(unsigned long addr,const struct module * mod)821 static inline bool within_module(unsigned long addr, const struct module *mod)
822 {
823 return false;
824 }
825
826 /* Get/put a kernel symbol (calls should be symmetric) */
827 #define symbol_get(x) ({ extern typeof(x) x __attribute__((weak,visibility("hidden"))); &(x); })
828 #define symbol_put(x) do { } while (0)
829 #define symbol_put_addr(x) do { } while (0)
830
__module_get(struct module * module)831 static inline void __module_get(struct module *module)
832 {
833 }
834
try_module_get(struct module * module)835 static inline bool try_module_get(struct module *module)
836 {
837 return true;
838 }
839
module_put(struct module * module)840 static inline void module_put(struct module *module)
841 {
842 }
843
844 #define module_name(mod) "kernel"
845
register_module_notifier(struct notifier_block * nb)846 static inline int register_module_notifier(struct notifier_block *nb)
847 {
848 /* no events will happen anyway, so this can always succeed */
849 return 0;
850 }
851
unregister_module_notifier(struct notifier_block * nb)852 static inline int unregister_module_notifier(struct notifier_block *nb)
853 {
854 return 0;
855 }
856
857 #define module_put_and_kthread_exit(code) kthread_exit(code)
858
print_modules(void)859 static inline void print_modules(void)
860 {
861 }
862
module_requested_async_probing(struct module * module)863 static inline bool module_requested_async_probing(struct module *module)
864 {
865 return false;
866 }
867
868
869 /* Dereference module function descriptor */
870 static inline
dereference_module_function_descriptor(struct module * mod,void * ptr)871 void *dereference_module_function_descriptor(struct module *mod, void *ptr)
872 {
873 return ptr;
874 }
875
module_is_coming(struct module * mod)876 static inline bool module_is_coming(struct module *mod)
877 {
878 return false;
879 }
880
module_for_each_mod(int (* func)(struct module * mod,void * data),void * data)881 static inline void module_for_each_mod(int(*func)(struct module *mod, void *data), void *data)
882 {
883 }
884 #endif /* CONFIG_MODULES */
885
886 #ifdef CONFIG_SYSFS
887 extern struct kset *module_kset;
888 extern const struct kobj_type module_ktype;
889 #endif /* CONFIG_SYSFS */
890
891 #define symbol_request(x) try_then_request_module(symbol_get(x), "symbol:" #x)
892
893 /* BELOW HERE ALL THESE ARE OBSOLETE AND WILL VANISH */
894
895 #define __MODULE_STRING(x) __stringify(x)
896
897 #ifdef CONFIG_GENERIC_BUG
898 void module_bug_finalize(const Elf_Ehdr *, const Elf_Shdr *,
899 struct module *);
900 void module_bug_cleanup(struct module *);
901
902 #else /* !CONFIG_GENERIC_BUG */
903
module_bug_finalize(const Elf_Ehdr * hdr,const Elf_Shdr * sechdrs,struct module * mod)904 static inline void module_bug_finalize(const Elf_Ehdr *hdr,
905 const Elf_Shdr *sechdrs,
906 struct module *mod)
907 {
908 }
module_bug_cleanup(struct module * mod)909 static inline void module_bug_cleanup(struct module *mod) {}
910 #endif /* CONFIG_GENERIC_BUG */
911
912 #ifdef CONFIG_MITIGATION_RETPOLINE
913 extern bool retpoline_module_ok(bool has_retpoline);
914 #else
retpoline_module_ok(bool has_retpoline)915 static inline bool retpoline_module_ok(bool has_retpoline)
916 {
917 return true;
918 }
919 #endif
920
921 #ifdef CONFIG_MODULE_SIG
922 bool is_module_sig_enforced(void);
923
924 void set_module_sig_enforced(void);
925
module_sig_ok(struct module * module)926 static inline bool module_sig_ok(struct module *module)
927 {
928 return module->sig_ok;
929 }
930 #else /* !CONFIG_MODULE_SIG */
is_module_sig_enforced(void)931 static inline bool is_module_sig_enforced(void)
932 {
933 return false;
934 }
935
set_module_sig_enforced(void)936 static inline void set_module_sig_enforced(void)
937 {
938 }
939
module_sig_ok(struct module * module)940 static inline bool module_sig_ok(struct module *module)
941 {
942 return true;
943 }
944 #endif /* CONFIG_MODULE_SIG */
945
946 #if defined(CONFIG_MODULES) && defined(CONFIG_KALLSYMS)
947 int module_kallsyms_on_each_symbol(const char *modname,
948 int (*fn)(void *, const char *, unsigned long),
949 void *data);
950
951 /* For kallsyms to ask for address resolution. namebuf should be at
952 * least KSYM_NAME_LEN long: a pointer to namebuf is returned if
953 * found, otherwise NULL.
954 */
955 int module_address_lookup(unsigned long addr,
956 unsigned long *symbolsize,
957 unsigned long *offset,
958 char **modname, const unsigned char **modbuildid,
959 char *namebuf);
960 int lookup_module_symbol_name(unsigned long addr, char *symname);
961 int lookup_module_symbol_attrs(unsigned long addr,
962 unsigned long *size,
963 unsigned long *offset,
964 char *modname,
965 char *name);
966
967 /* Returns 0 and fills in value, defined and namebuf, or -ERANGE if
968 * symnum out of range.
969 */
970 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
971 char *name, char *module_name, int *exported);
972
973 /* Look for this name: can be of form module:name. */
974 unsigned long module_kallsyms_lookup_name(const char *name);
975
976 unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name);
977
978 #else /* CONFIG_MODULES && CONFIG_KALLSYMS */
979
module_kallsyms_on_each_symbol(const char * modname,int (* fn)(void *,const char *,unsigned long),void * data)980 static inline int module_kallsyms_on_each_symbol(const char *modname,
981 int (*fn)(void *, const char *, unsigned long),
982 void *data)
983 {
984 return -EOPNOTSUPP;
985 }
986
987 /* For kallsyms to ask for address resolution. NULL means not found. */
module_address_lookup(unsigned long addr,unsigned long * symbolsize,unsigned long * offset,char ** modname,const unsigned char ** modbuildid,char * namebuf)988 static inline int module_address_lookup(unsigned long addr,
989 unsigned long *symbolsize,
990 unsigned long *offset,
991 char **modname,
992 const unsigned char **modbuildid,
993 char *namebuf)
994 {
995 return 0;
996 }
997
lookup_module_symbol_name(unsigned long addr,char * symname)998 static inline int lookup_module_symbol_name(unsigned long addr, char *symname)
999 {
1000 return -ERANGE;
1001 }
1002
module_get_kallsym(unsigned int symnum,unsigned long * value,char * type,char * name,char * module_name,int * exported)1003 static inline int module_get_kallsym(unsigned int symnum, unsigned long *value,
1004 char *type, char *name,
1005 char *module_name, int *exported)
1006 {
1007 return -ERANGE;
1008 }
1009
module_kallsyms_lookup_name(const char * name)1010 static inline unsigned long module_kallsyms_lookup_name(const char *name)
1011 {
1012 return 0;
1013 }
1014
find_kallsyms_symbol_value(struct module * mod,const char * name)1015 static inline unsigned long find_kallsyms_symbol_value(struct module *mod,
1016 const char *name)
1017 {
1018 return 0;
1019 }
1020
1021 #endif /* CONFIG_MODULES && CONFIG_KALLSYMS */
1022
1023 /* Define __free(module_put) macro for struct module *. */
1024 DEFINE_FREE(module_put, struct module *, if (_T) module_put(_T))
1025
1026 #endif /* _LINUX_MODULE_H */
1027