xref: /linux/include/linux/module.h (revision 69b54314c975f4dfd3a29d6b9211ab68fff46682)
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/kmod.h>
18 #include <linux/init.h>
19 #include <linux/elf.h>
20 #include <linux/stringify.h>
21 #include <linux/kobject.h>
22 #include <linux/moduleparam.h>
23 #include <linux/jump_label.h>
24 #include <linux/export.h>
25 #include <linux/rbtree_latch.h>
26 #include <linux/error-injection.h>
27 #include <linux/tracepoint-defs.h>
28 #include <linux/srcu.h>
29 #include <linux/static_call_types.h>
30 #include <linux/dynamic_debug.h>
31 
32 #include <linux/percpu.h>
33 #include <asm/module.h>
34 
35 #define MODULE_NAME_LEN MAX_PARAM_PREFIX_LEN
36 
37 struct modversion_info {
38 	unsigned long crc;
39 	char name[MODULE_NAME_LEN];
40 };
41 
42 struct module;
43 struct exception_table_entry;
44 
45 struct module_kobject {
46 	struct kobject kobj;
47 	struct module *mod;
48 	struct kobject *drivers_dir;
49 	struct module_param_attrs *mp;
50 	struct completion *kobj_completion;
51 } __randomize_layout;
52 
53 struct module_attribute {
54 	struct attribute attr;
55 	ssize_t (*show)(const struct module_attribute *, struct module_kobject *,
56 			char *);
57 	ssize_t (*store)(const struct module_attribute *, struct module_kobject *,
58 			 const char *, size_t count);
59 	void (*setup)(struct module *, const char *);
60 	int (*test)(struct module *);
61 	void (*free)(struct module *);
62 };
63 
64 struct module_version_attribute {
65 	struct module_attribute mattr;
66 	const char *module_name;
67 	const char *version;
68 };
69 
70 extern ssize_t __modver_version_show(const struct module_attribute *,
71 				     struct module_kobject *, char *);
72 
73 extern const struct module_attribute module_uevent;
74 
75 /* These are either module local, or the kernel's dummy ones. */
76 extern int init_module(void);
77 extern void cleanup_module(void);
78 
79 #ifndef MODULE
80 /**
81  * module_init() - driver initialization entry point
82  * @x: function to be run at kernel boot time or module insertion
83  *
84  * module_init() will either be called during do_initcalls() (if
85  * builtin) or at module insertion time (if a module).  There can only
86  * be one per module.
87  */
88 #define module_init(x)	__initcall(x);
89 
90 /**
91  * module_exit() - driver exit entry point
92  * @x: function to be run when driver is removed
93  *
94  * module_exit() will wrap the driver clean-up code
95  * with cleanup_module() when used with rmmod when
96  * the driver is a module.  If the driver is statically
97  * compiled into the kernel, module_exit() has no effect.
98  * There can only be one per module.
99  */
100 #define module_exit(x)	__exitcall(x);
101 
102 #else /* MODULE */
103 
104 /*
105  * In most cases loadable modules do not need custom
106  * initcall levels. There are still some valid cases where
107  * a driver may be needed early if built in, and does not
108  * matter when built as a loadable module. Like bus
109  * snooping debug drivers.
110  */
111 #define early_initcall(fn)		module_init(fn)
112 #define core_initcall(fn)		module_init(fn)
113 #define core_initcall_sync(fn)		module_init(fn)
114 #define postcore_initcall(fn)		module_init(fn)
115 #define postcore_initcall_sync(fn)	module_init(fn)
116 #define arch_initcall(fn)		module_init(fn)
117 #define subsys_initcall(fn)		module_init(fn)
118 #define subsys_initcall_sync(fn)	module_init(fn)
119 #define fs_initcall(fn)			module_init(fn)
120 #define fs_initcall_sync(fn)		module_init(fn)
121 #define rootfs_initcall(fn)		module_init(fn)
122 #define device_initcall(fn)		module_init(fn)
123 #define device_initcall_sync(fn)	module_init(fn)
124 #define late_initcall(fn)		module_init(fn)
125 #define late_initcall_sync(fn)		module_init(fn)
126 
127 #define console_initcall(fn)		module_init(fn)
128 
129 /* Each module must use one module_init(). */
130 #define module_init(initfn)					\
131 	static inline initcall_t __maybe_unused __inittest(void)		\
132 	{ return initfn; }					\
133 	int init_module(void) __copy(initfn)			\
134 		__attribute__((alias(#initfn)));		\
135 	___ADDRESSABLE(init_module, __initdata);
136 
137 /* This is only required if you want to be unloadable. */
138 #define module_exit(exitfn)					\
139 	static inline exitcall_t __maybe_unused __exittest(void)		\
140 	{ return exitfn; }					\
141 	void cleanup_module(void) __copy(exitfn)		\
142 		__attribute__((alias(#exitfn)));		\
143 	___ADDRESSABLE(cleanup_module, __exitdata);
144 
145 #endif
146 
147 /* This means "can be init if no module support, otherwise module load
148    may call it." */
149 #ifdef CONFIG_MODULES
150 #define __init_or_module
151 #define __initdata_or_module
152 #define __initconst_or_module
153 #define __INIT_OR_MODULE	.text
154 #define __INITDATA_OR_MODULE	.data
155 #define __INITRODATA_OR_MODULE	.section ".rodata","a",%progbits
156 #else
157 #define __init_or_module __init
158 #define __initdata_or_module __initdata
159 #define __initconst_or_module __initconst
160 #define __INIT_OR_MODULE __INIT
161 #define __INITDATA_OR_MODULE __INITDATA
162 #define __INITRODATA_OR_MODULE __INITRODATA
163 #endif /*CONFIG_MODULES*/
164 
165 /* Generic info of form tag = "info" */
166 #define MODULE_INFO(tag, info) __MODULE_INFO(tag, tag, info)
167 
168 /* For userspace: you can also call me... */
169 #define MODULE_ALIAS(_alias) MODULE_INFO(alias, _alias)
170 
171 /* Soft module dependencies. See man modprobe.d for details.
172  * Example: MODULE_SOFTDEP("pre: module-foo module-bar post: module-baz")
173  */
174 #define MODULE_SOFTDEP(_softdep) MODULE_INFO(softdep, _softdep)
175 
176 /*
177  * Weak module dependencies. See man modprobe.d for details.
178  * Example: MODULE_WEAKDEP("module-foo")
179  */
180 #define MODULE_WEAKDEP(_weakdep) MODULE_INFO(weakdep, _weakdep)
181 
182 /*
183  * MODULE_FILE is used for generating modules.builtin
184  * So, make it no-op when this is being built as a module
185  */
186 #ifdef MODULE
187 #define MODULE_FILE
188 #else
189 #define MODULE_FILE	MODULE_INFO(file, KBUILD_MODFILE);
190 #endif
191 
192 /*
193  * The following license idents are currently accepted as indicating free
194  * software modules
195  *
196  *	"GPL"				[GNU Public License v2]
197  *	"GPL v2"			[GNU Public License v2]
198  *	"GPL and additional rights"	[GNU Public License v2 rights and more]
199  *	"Dual BSD/GPL"			[GNU Public License v2
200  *					 or BSD license choice]
201  *	"Dual MIT/GPL"			[GNU Public License v2
202  *					 or MIT license choice]
203  *	"Dual MPL/GPL"			[GNU Public License v2
204  *					 or Mozilla license choice]
205  *
206  * The following other idents are available
207  *
208  *	"Proprietary"			[Non free products]
209  *
210  * Both "GPL v2" and "GPL" (the latter also in dual licensed strings) are
211  * merely stating that the module is licensed under the GPL v2, but are not
212  * telling whether "GPL v2 only" or "GPL v2 or later". The reason why there
213  * are two variants is a historic and failed attempt to convey more
214  * information in the MODULE_LICENSE string. For module loading the
215  * "only/or later" distinction is completely irrelevant and does neither
216  * replace the proper license identifiers in the corresponding source file
217  * nor amends them in any way. The sole purpose is to make the
218  * 'Proprietary' flagging work and to refuse to bind symbols which are
219  * exported with EXPORT_SYMBOL_GPL when a non free module is loaded.
220  *
221  * In the same way "BSD" is not a clear license information. It merely
222  * states, that the module is licensed under one of the compatible BSD
223  * license variants. The detailed and correct license information is again
224  * to be found in the corresponding source files.
225  *
226  * There are dual licensed components, but when running with Linux it is the
227  * GPL that is relevant so this is a non issue. Similarly LGPL linked with GPL
228  * is a GPL combined work.
229  *
230  * This exists for several reasons
231  * 1.	So modinfo can show license info for users wanting to vet their setup
232  *	is free
233  * 2.	So the community can ignore bug reports including proprietary modules
234  * 3.	So vendors can do likewise based on their own policies
235  */
236 #define MODULE_LICENSE(_license) MODULE_FILE MODULE_INFO(license, _license)
237 
238 /*
239  * Author(s), use "Name <email>" or just "Name", for multiple
240  * authors use multiple MODULE_AUTHOR() statements/lines.
241  */
242 #define MODULE_AUTHOR(_author) MODULE_INFO(author, _author)
243 
244 /* What your module does. */
245 #define MODULE_DESCRIPTION(_description) MODULE_INFO(description, _description)
246 
247 #ifdef MODULE
248 /* Creates an alias so file2alias.c can find device table. */
249 #define MODULE_DEVICE_TABLE(type, name)					\
250 extern typeof(name) __mod_device_table__##type##__##name		\
251   __attribute__ ((unused, alias(__stringify(name))))
252 #else  /* !MODULE */
253 #define MODULE_DEVICE_TABLE(type, name)
254 #endif
255 
256 /* Version of form [<epoch>:]<version>[-<extra-version>].
257  * Or for CVS/RCS ID version, everything but the number is stripped.
258  * <epoch>: A (small) unsigned integer which allows you to start versions
259  * anew. If not mentioned, it's zero.  eg. "2:1.0" is after
260  * "1:2.0".
261 
262  * <version>: The <version> may contain only alphanumerics and the
263  * character `.'.  Ordered by numeric sort for numeric parts,
264  * ascii sort for ascii parts (as per RPM or DEB algorithm).
265 
266  * <extraversion>: Like <version>, but inserted for local
267  * customizations, eg "rh3" or "rusty1".
268 
269  * Using this automatically adds a checksum of the .c files and the
270  * local headers in "srcversion".
271  */
272 
273 #if defined(MODULE) || !defined(CONFIG_SYSFS)
274 #define MODULE_VERSION(_version) MODULE_INFO(version, _version)
275 #else
276 #define MODULE_VERSION(_version)					\
277 	MODULE_INFO(version, _version);					\
278 	static const struct module_version_attribute __modver_attr	\
279 		__used __section("__modver")				\
280 		__aligned(__alignof__(struct module_version_attribute)) \
281 		= {							\
282 			.mattr	= {					\
283 				.attr	= {				\
284 					.name	= "version",		\
285 					.mode	= S_IRUGO,		\
286 				},					\
287 				.show	= __modver_version_show,	\
288 			},						\
289 			.module_name	= KBUILD_MODNAME,		\
290 			.version	= _version,			\
291 		}
292 #endif
293 
294 /* Optional firmware file (or files) needed by the module
295  * format is simply firmware file name.  Multiple firmware
296  * files require multiple MODULE_FIRMWARE() specifiers */
297 #define MODULE_FIRMWARE(_firmware) MODULE_INFO(firmware, _firmware)
298 
299 #define MODULE_IMPORT_NS(ns)	MODULE_INFO(import_ns, ns)
300 
301 struct notifier_block;
302 
303 #ifdef CONFIG_MODULES
304 
305 extern int modules_disabled; /* for sysctl */
306 /* Get/put a kernel symbol (calls must be symmetric) */
307 void *__symbol_get(const char *symbol);
308 void *__symbol_get_gpl(const char *symbol);
309 #define symbol_get(x)	({ \
310 	static const char __notrim[] \
311 		__used __section(".no_trim_symbol") = __stringify(x); \
312 	(typeof(&x))(__symbol_get(__stringify(x))); })
313 
314 /* modules using other modules: kdb wants to see this. */
315 struct module_use {
316 	struct list_head source_list;
317 	struct list_head target_list;
318 	struct module *source, *target;
319 };
320 
321 enum module_state {
322 	MODULE_STATE_LIVE,	/* Normal state. */
323 	MODULE_STATE_COMING,	/* Full formed, running module_init. */
324 	MODULE_STATE_GOING,	/* Going away. */
325 	MODULE_STATE_UNFORMED,	/* Still setting it up. */
326 };
327 
328 struct mod_tree_node {
329 	struct module *mod;
330 	struct latch_tree_node node;
331 };
332 
333 enum mod_mem_type {
334 	MOD_TEXT = 0,
335 	MOD_DATA,
336 	MOD_RODATA,
337 	MOD_RO_AFTER_INIT,
338 	MOD_INIT_TEXT,
339 	MOD_INIT_DATA,
340 	MOD_INIT_RODATA,
341 
342 	MOD_MEM_NUM_TYPES,
343 	MOD_INVALID = -1,
344 };
345 
346 #define mod_mem_type_is_init(type)	\
347 	((type) == MOD_INIT_TEXT ||	\
348 	 (type) == MOD_INIT_DATA ||	\
349 	 (type) == MOD_INIT_RODATA)
350 
351 #define mod_mem_type_is_core(type) (!mod_mem_type_is_init(type))
352 
353 #define mod_mem_type_is_text(type)	\
354 	 ((type) == MOD_TEXT ||		\
355 	  (type) == MOD_INIT_TEXT)
356 
357 #define mod_mem_type_is_data(type) (!mod_mem_type_is_text(type))
358 
359 #define mod_mem_type_is_core_data(type)	\
360 	(mod_mem_type_is_core(type) &&	\
361 	 mod_mem_type_is_data(type))
362 
363 #define for_each_mod_mem_type(type)			\
364 	for (enum mod_mem_type (type) = 0;		\
365 	     (type) < MOD_MEM_NUM_TYPES; (type)++)
366 
367 #define for_class_mod_mem_type(type, class)		\
368 	for_each_mod_mem_type(type)			\
369 		if (mod_mem_type_is_##class(type))
370 
371 struct module_memory {
372 	void *base;
373 	void *rw_copy;
374 	bool is_rox;
375 	unsigned int size;
376 
377 #ifdef CONFIG_MODULES_TREE_LOOKUP
378 	struct mod_tree_node mtn;
379 #endif
380 };
381 
382 #ifdef CONFIG_MODULES_TREE_LOOKUP
383 /* Only touch one cacheline for common rbtree-for-core-layout case. */
384 #define __module_memory_align ____cacheline_aligned
385 #else
386 #define __module_memory_align
387 #endif
388 
389 struct mod_kallsyms {
390 	Elf_Sym *symtab;
391 	unsigned int num_symtab;
392 	char *strtab;
393 	char *typetab;
394 };
395 
396 #ifdef CONFIG_LIVEPATCH
397 /**
398  * struct klp_modinfo - ELF information preserved from the livepatch module
399  *
400  * @hdr: ELF header
401  * @sechdrs: Section header table
402  * @secstrings: String table for the section headers
403  * @symndx: The symbol table section index
404  */
405 struct klp_modinfo {
406 	Elf_Ehdr hdr;
407 	Elf_Shdr *sechdrs;
408 	char *secstrings;
409 	unsigned int symndx;
410 };
411 #endif
412 
413 struct module {
414 	enum module_state state;
415 
416 	/* Member of list of modules */
417 	struct list_head list;
418 
419 	/* Unique handle for this module */
420 	char name[MODULE_NAME_LEN];
421 
422 #ifdef CONFIG_STACKTRACE_BUILD_ID
423 	/* Module build ID */
424 	unsigned char build_id[BUILD_ID_SIZE_MAX];
425 #endif
426 
427 	/* Sysfs stuff. */
428 	struct module_kobject mkobj;
429 	struct module_attribute *modinfo_attrs;
430 	const char *version;
431 	const char *srcversion;
432 	struct kobject *holders_dir;
433 
434 	/* Exported symbols */
435 	const struct kernel_symbol *syms;
436 	const u32 *crcs;
437 	unsigned int num_syms;
438 
439 #ifdef CONFIG_ARCH_USES_CFI_TRAPS
440 	s32 *kcfi_traps;
441 	s32 *kcfi_traps_end;
442 #endif
443 
444 	/* Kernel parameters. */
445 #ifdef CONFIG_SYSFS
446 	struct mutex param_lock;
447 #endif
448 	struct kernel_param *kp;
449 	unsigned int num_kp;
450 
451 	/* GPL-only exported symbols. */
452 	unsigned int num_gpl_syms;
453 	const struct kernel_symbol *gpl_syms;
454 	const u32 *gpl_crcs;
455 	bool using_gplonly_symbols;
456 
457 #ifdef CONFIG_MODULE_SIG
458 	/* Signature was verified. */
459 	bool sig_ok;
460 #endif
461 
462 	bool async_probe_requested;
463 
464 	/* Exception table */
465 	unsigned int num_exentries;
466 	struct exception_table_entry *extable;
467 
468 	/* Startup function. */
469 	int (*init)(void);
470 
471 	struct module_memory mem[MOD_MEM_NUM_TYPES] __module_memory_align;
472 
473 	/* Arch-specific module values */
474 	struct mod_arch_specific arch;
475 
476 	unsigned long taints;	/* same bits as kernel:taint_flags */
477 
478 #ifdef CONFIG_GENERIC_BUG
479 	/* Support for BUG */
480 	unsigned num_bugs;
481 	struct list_head bug_list;
482 	struct bug_entry *bug_table;
483 #endif
484 
485 #ifdef CONFIG_KALLSYMS
486 	/* Protected by RCU and/or module_mutex: use rcu_dereference() */
487 	struct mod_kallsyms __rcu *kallsyms;
488 	struct mod_kallsyms core_kallsyms;
489 
490 	/* Section attributes */
491 	struct module_sect_attrs *sect_attrs;
492 
493 	/* Notes attributes */
494 	struct module_notes_attrs *notes_attrs;
495 #endif
496 
497 	/* The command line arguments (may be mangled).  People like
498 	   keeping pointers to this stuff */
499 	char *args;
500 
501 #ifdef CONFIG_SMP
502 	/* Per-cpu data. */
503 	void __percpu *percpu;
504 	unsigned int percpu_size;
505 #endif
506 	void *noinstr_text_start;
507 	unsigned int noinstr_text_size;
508 
509 #ifdef CONFIG_TRACEPOINTS
510 	unsigned int num_tracepoints;
511 	tracepoint_ptr_t *tracepoints_ptrs;
512 #endif
513 #ifdef CONFIG_TREE_SRCU
514 	unsigned int num_srcu_structs;
515 	struct srcu_struct **srcu_struct_ptrs;
516 #endif
517 #ifdef CONFIG_BPF_EVENTS
518 	unsigned int num_bpf_raw_events;
519 	struct bpf_raw_event_map *bpf_raw_events;
520 #endif
521 #ifdef CONFIG_DEBUG_INFO_BTF_MODULES
522 	unsigned int btf_data_size;
523 	unsigned int btf_base_data_size;
524 	void *btf_data;
525 	void *btf_base_data;
526 #endif
527 #ifdef CONFIG_JUMP_LABEL
528 	struct jump_entry *jump_entries;
529 	unsigned int num_jump_entries;
530 #endif
531 #ifdef CONFIG_TRACING
532 	unsigned int num_trace_bprintk_fmt;
533 	const char **trace_bprintk_fmt_start;
534 #endif
535 #ifdef CONFIG_EVENT_TRACING
536 	struct trace_event_call **trace_events;
537 	unsigned int num_trace_events;
538 	struct trace_eval_map **trace_evals;
539 	unsigned int num_trace_evals;
540 #endif
541 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
542 	unsigned int num_ftrace_callsites;
543 	unsigned long *ftrace_callsites;
544 #endif
545 #ifdef CONFIG_KPROBES
546 	void *kprobes_text_start;
547 	unsigned int kprobes_text_size;
548 	unsigned long *kprobe_blacklist;
549 	unsigned int num_kprobe_blacklist;
550 #endif
551 #ifdef CONFIG_HAVE_STATIC_CALL_INLINE
552 	int num_static_call_sites;
553 	struct static_call_site *static_call_sites;
554 #endif
555 #if IS_ENABLED(CONFIG_KUNIT)
556 	int num_kunit_init_suites;
557 	struct kunit_suite **kunit_init_suites;
558 	int num_kunit_suites;
559 	struct kunit_suite **kunit_suites;
560 #endif
561 
562 
563 #ifdef CONFIG_LIVEPATCH
564 	bool klp; /* Is this a livepatch module? */
565 	bool klp_alive;
566 
567 	/* ELF information */
568 	struct klp_modinfo *klp_info;
569 #endif
570 
571 #ifdef CONFIG_PRINTK_INDEX
572 	unsigned int printk_index_size;
573 	struct pi_entry **printk_index_start;
574 #endif
575 
576 #ifdef CONFIG_MODULE_UNLOAD
577 	/* What modules depend on me? */
578 	struct list_head source_list;
579 	/* What modules do I depend on? */
580 	struct list_head target_list;
581 
582 	/* Destruction function. */
583 	void (*exit)(void);
584 
585 	atomic_t refcnt;
586 #endif
587 
588 #ifdef CONFIG_CONSTRUCTORS
589 	/* Constructor functions. */
590 	ctor_fn_t *ctors;
591 	unsigned int num_ctors;
592 #endif
593 
594 #ifdef CONFIG_FUNCTION_ERROR_INJECTION
595 	struct error_injection_entry *ei_funcs;
596 	unsigned int num_ei_funcs;
597 #endif
598 #ifdef CONFIG_DYNAMIC_DEBUG_CORE
599 	struct _ddebug_info dyndbg_info;
600 #endif
601 } ____cacheline_aligned __randomize_layout;
602 #ifndef MODULE_ARCH_INIT
603 #define MODULE_ARCH_INIT {}
604 #endif
605 
606 #ifndef HAVE_ARCH_KALLSYMS_SYMBOL_VALUE
kallsyms_symbol_value(const Elf_Sym * sym)607 static inline unsigned long kallsyms_symbol_value(const Elf_Sym *sym)
608 {
609 	return sym->st_value;
610 }
611 #endif
612 
613 /* FIXME: It'd be nice to isolate modules during init, too, so they
614    aren't used before they (may) fail.  But presently too much code
615    (IDE & SCSI) require entry into the module during init.*/
module_is_live(struct module * mod)616 static inline bool module_is_live(struct module *mod)
617 {
618 	return mod->state != MODULE_STATE_GOING;
619 }
620 
module_is_coming(struct module * mod)621 static inline bool module_is_coming(struct module *mod)
622 {
623         return mod->state == MODULE_STATE_COMING;
624 }
625 
626 struct module *__module_text_address(unsigned long addr);
627 struct module *__module_address(unsigned long addr);
628 bool is_module_address(unsigned long addr);
629 bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr);
630 bool is_module_percpu_address(unsigned long addr);
631 bool is_module_text_address(unsigned long addr);
632 
within_module_mem_type(unsigned long addr,const struct module * mod,enum mod_mem_type type)633 static inline bool within_module_mem_type(unsigned long addr,
634 					  const struct module *mod,
635 					  enum mod_mem_type type)
636 {
637 	unsigned long base, size;
638 
639 	base = (unsigned long)mod->mem[type].base;
640 	size = mod->mem[type].size;
641 	return addr - base < size;
642 }
643 
within_module_core(unsigned long addr,const struct module * mod)644 static inline bool within_module_core(unsigned long addr,
645 				      const struct module *mod)
646 {
647 	for_class_mod_mem_type(type, core) {
648 		if (within_module_mem_type(addr, mod, type))
649 			return true;
650 	}
651 	return false;
652 }
653 
within_module_init(unsigned long addr,const struct module * mod)654 static inline bool within_module_init(unsigned long addr,
655 				      const struct module *mod)
656 {
657 	for_class_mod_mem_type(type, init) {
658 		if (within_module_mem_type(addr, mod, type))
659 			return true;
660 	}
661 	return false;
662 }
663 
within_module(unsigned long addr,const struct module * mod)664 static inline bool within_module(unsigned long addr, const struct module *mod)
665 {
666 	return within_module_init(addr, mod) || within_module_core(addr, mod);
667 }
668 
669 /* Search for module by name: must be in a RCU-sched critical section. */
670 struct module *find_module(const char *name);
671 
672 extern void __noreturn __module_put_and_kthread_exit(struct module *mod,
673 			long code);
674 #define module_put_and_kthread_exit(code) __module_put_and_kthread_exit(THIS_MODULE, code)
675 
676 #ifdef CONFIG_MODULE_UNLOAD
677 int module_refcount(struct module *mod);
678 void __symbol_put(const char *symbol);
679 #define symbol_put(x) __symbol_put(__stringify(x))
680 void symbol_put_addr(void *addr);
681 
682 /* Sometimes we know we already have a refcount, and it's easier not
683    to handle the error case (which only happens with rmmod --wait). */
684 extern void __module_get(struct module *module);
685 
686 /**
687  * try_module_get() - take module refcount unless module is being removed
688  * @module: the module we should check for
689  *
690  * Only try to get a module reference count if the module is not being removed.
691  * This call will fail if the module is in the process of being removed.
692  *
693  * Care must also be taken to ensure the module exists and is alive prior to
694  * usage of this call. This can be gauranteed through two means:
695  *
696  * 1) Direct protection: you know an earlier caller must have increased the
697  *    module reference through __module_get(). This can typically be achieved
698  *    by having another entity other than the module itself increment the
699  *    module reference count.
700  *
701  * 2) Implied protection: there is an implied protection against module
702  *    removal. An example of this is the implied protection used by kernfs /
703  *    sysfs. The sysfs store / read file operations are guaranteed to exist
704  *    through the use of kernfs's active reference (see kernfs_active()) and a
705  *    sysfs / kernfs file removal cannot happen unless the same file is not
706  *    active. Therefore, if a sysfs file is being read or written to the module
707  *    which created it must still exist. It is therefore safe to use
708  *    try_module_get() on module sysfs store / read ops.
709  *
710  * One of the real values to try_module_get() is the module_is_live() check
711  * which ensures that the caller of try_module_get() can yield to userspace
712  * module removal requests and gracefully fail if the module is on its way out.
713  *
714  * Returns true if the reference count was successfully incremented.
715  */
716 extern bool try_module_get(struct module *module);
717 
718 /**
719  * module_put() - release a reference count to a module
720  * @module: the module we should release a reference count for
721  *
722  * If you successfully bump a reference count to a module with try_module_get(),
723  * when you are finished you must call module_put() to release that reference
724  * count.
725  */
726 extern void module_put(struct module *module);
727 
728 #else /*!CONFIG_MODULE_UNLOAD*/
try_module_get(struct module * module)729 static inline bool try_module_get(struct module *module)
730 {
731 	return !module || module_is_live(module);
732 }
module_put(struct module * module)733 static inline void module_put(struct module *module)
734 {
735 }
__module_get(struct module * module)736 static inline void __module_get(struct module *module)
737 {
738 }
739 #define symbol_put(x) do { } while (0)
740 #define symbol_put_addr(p) do { } while (0)
741 
742 #endif /* CONFIG_MODULE_UNLOAD */
743 
744 /* This is a #define so the string doesn't get put in every .o file */
745 #define module_name(mod)			\
746 ({						\
747 	struct module *__mod = (mod);		\
748 	__mod ? __mod->name : "kernel";		\
749 })
750 
751 /* Dereference module function descriptor */
752 void *dereference_module_function_descriptor(struct module *mod, void *ptr);
753 
754 int register_module_notifier(struct notifier_block *nb);
755 int unregister_module_notifier(struct notifier_block *nb);
756 
757 extern void print_modules(void);
758 
module_requested_async_probing(struct module * module)759 static inline bool module_requested_async_probing(struct module *module)
760 {
761 	return module && module->async_probe_requested;
762 }
763 
is_livepatch_module(struct module * mod)764 static inline bool is_livepatch_module(struct module *mod)
765 {
766 #ifdef CONFIG_LIVEPATCH
767 	return mod->klp;
768 #else
769 	return false;
770 #endif
771 }
772 
773 void set_module_sig_enforced(void);
774 
775 void *__module_writable_address(struct module *mod, void *loc);
776 
module_writable_address(struct module * mod,void * loc)777 static inline void *module_writable_address(struct module *mod, void *loc)
778 {
779 	if (!IS_ENABLED(CONFIG_ARCH_HAS_EXECMEM_ROX) || !mod ||
780 	    mod->state != MODULE_STATE_UNFORMED)
781 		return loc;
782 	return __module_writable_address(mod, loc);
783 }
784 
785 #else /* !CONFIG_MODULES... */
786 
__module_address(unsigned long addr)787 static inline struct module *__module_address(unsigned long addr)
788 {
789 	return NULL;
790 }
791 
__module_text_address(unsigned long addr)792 static inline struct module *__module_text_address(unsigned long addr)
793 {
794 	return NULL;
795 }
796 
is_module_address(unsigned long addr)797 static inline bool is_module_address(unsigned long addr)
798 {
799 	return false;
800 }
801 
is_module_percpu_address(unsigned long addr)802 static inline bool is_module_percpu_address(unsigned long addr)
803 {
804 	return false;
805 }
806 
__is_module_percpu_address(unsigned long addr,unsigned long * can_addr)807 static inline bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr)
808 {
809 	return false;
810 }
811 
is_module_text_address(unsigned long addr)812 static inline bool is_module_text_address(unsigned long addr)
813 {
814 	return false;
815 }
816 
within_module_core(unsigned long addr,const struct module * mod)817 static inline bool within_module_core(unsigned long addr,
818 				      const struct module *mod)
819 {
820 	return false;
821 }
822 
within_module_init(unsigned long addr,const struct module * mod)823 static inline bool within_module_init(unsigned long addr,
824 				      const struct module *mod)
825 {
826 	return false;
827 }
828 
within_module(unsigned long addr,const struct module * mod)829 static inline bool within_module(unsigned long addr, const struct module *mod)
830 {
831 	return false;
832 }
833 
834 /* Get/put a kernel symbol (calls should be symmetric) */
835 #define symbol_get(x) ({ extern typeof(x) x __attribute__((weak,visibility("hidden"))); &(x); })
836 #define symbol_put(x) do { } while (0)
837 #define symbol_put_addr(x) do { } while (0)
838 
__module_get(struct module * module)839 static inline void __module_get(struct module *module)
840 {
841 }
842 
try_module_get(struct module * module)843 static inline bool try_module_get(struct module *module)
844 {
845 	return true;
846 }
847 
module_put(struct module * module)848 static inline void module_put(struct module *module)
849 {
850 }
851 
852 #define module_name(mod) "kernel"
853 
register_module_notifier(struct notifier_block * nb)854 static inline int register_module_notifier(struct notifier_block *nb)
855 {
856 	/* no events will happen anyway, so this can always succeed */
857 	return 0;
858 }
859 
unregister_module_notifier(struct notifier_block * nb)860 static inline int unregister_module_notifier(struct notifier_block *nb)
861 {
862 	return 0;
863 }
864 
865 #define module_put_and_kthread_exit(code) kthread_exit(code)
866 
print_modules(void)867 static inline void print_modules(void)
868 {
869 }
870 
module_requested_async_probing(struct module * module)871 static inline bool module_requested_async_probing(struct module *module)
872 {
873 	return false;
874 }
875 
876 
set_module_sig_enforced(void)877 static inline void set_module_sig_enforced(void)
878 {
879 }
880 
881 /* Dereference module function descriptor */
882 static inline
dereference_module_function_descriptor(struct module * mod,void * ptr)883 void *dereference_module_function_descriptor(struct module *mod, void *ptr)
884 {
885 	return ptr;
886 }
887 
module_is_coming(struct module * mod)888 static inline bool module_is_coming(struct module *mod)
889 {
890 	return false;
891 }
892 
module_writable_address(struct module * mod,void * loc)893 static inline void *module_writable_address(struct module *mod, void *loc)
894 {
895 	return loc;
896 }
897 #endif /* CONFIG_MODULES */
898 
899 #ifdef CONFIG_SYSFS
900 extern struct kset *module_kset;
901 extern const struct kobj_type module_ktype;
902 #endif /* CONFIG_SYSFS */
903 
904 #define symbol_request(x) try_then_request_module(symbol_get(x), "symbol:" #x)
905 
906 /* BELOW HERE ALL THESE ARE OBSOLETE AND WILL VANISH */
907 
908 #define __MODULE_STRING(x) __stringify(x)
909 
910 #ifdef CONFIG_GENERIC_BUG
911 void module_bug_finalize(const Elf_Ehdr *, const Elf_Shdr *,
912 			 struct module *);
913 void module_bug_cleanup(struct module *);
914 
915 #else	/* !CONFIG_GENERIC_BUG */
916 
module_bug_finalize(const Elf_Ehdr * hdr,const Elf_Shdr * sechdrs,struct module * mod)917 static inline void module_bug_finalize(const Elf_Ehdr *hdr,
918 					const Elf_Shdr *sechdrs,
919 					struct module *mod)
920 {
921 }
module_bug_cleanup(struct module * mod)922 static inline void module_bug_cleanup(struct module *mod) {}
923 #endif	/* CONFIG_GENERIC_BUG */
924 
925 #ifdef CONFIG_MITIGATION_RETPOLINE
926 extern bool retpoline_module_ok(bool has_retpoline);
927 #else
retpoline_module_ok(bool has_retpoline)928 static inline bool retpoline_module_ok(bool has_retpoline)
929 {
930 	return true;
931 }
932 #endif
933 
934 #ifdef CONFIG_MODULE_SIG
935 bool is_module_sig_enforced(void);
936 
module_sig_ok(struct module * module)937 static inline bool module_sig_ok(struct module *module)
938 {
939 	return module->sig_ok;
940 }
941 #else	/* !CONFIG_MODULE_SIG */
is_module_sig_enforced(void)942 static inline bool is_module_sig_enforced(void)
943 {
944 	return false;
945 }
946 
module_sig_ok(struct module * module)947 static inline bool module_sig_ok(struct module *module)
948 {
949 	return true;
950 }
951 #endif	/* CONFIG_MODULE_SIG */
952 
953 #if defined(CONFIG_MODULES) && defined(CONFIG_KALLSYMS)
954 int module_kallsyms_on_each_symbol(const char *modname,
955 				   int (*fn)(void *, const char *, unsigned long),
956 				   void *data);
957 
958 /* For kallsyms to ask for address resolution.  namebuf should be at
959  * least KSYM_NAME_LEN long: a pointer to namebuf is returned if
960  * found, otherwise NULL.
961  */
962 int module_address_lookup(unsigned long addr,
963 			  unsigned long *symbolsize,
964 			  unsigned long *offset,
965 			  char **modname, const unsigned char **modbuildid,
966 			  char *namebuf);
967 int lookup_module_symbol_name(unsigned long addr, char *symname);
968 int lookup_module_symbol_attrs(unsigned long addr,
969 			       unsigned long *size,
970 			       unsigned long *offset,
971 			       char *modname,
972 			       char *name);
973 
974 /* Returns 0 and fills in value, defined and namebuf, or -ERANGE if
975  * symnum out of range.
976  */
977 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
978 		       char *name, char *module_name, int *exported);
979 
980 /* Look for this name: can be of form module:name. */
981 unsigned long module_kallsyms_lookup_name(const char *name);
982 
983 unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name);
984 
985 #else	/* CONFIG_MODULES && CONFIG_KALLSYMS */
986 
module_kallsyms_on_each_symbol(const char * modname,int (* fn)(void *,const char *,unsigned long),void * data)987 static inline int module_kallsyms_on_each_symbol(const char *modname,
988 						 int (*fn)(void *, const char *, unsigned long),
989 						 void *data)
990 {
991 	return -EOPNOTSUPP;
992 }
993 
994 /* 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)995 static inline int module_address_lookup(unsigned long addr,
996 						unsigned long *symbolsize,
997 						unsigned long *offset,
998 						char **modname,
999 						const unsigned char **modbuildid,
1000 						char *namebuf)
1001 {
1002 	return 0;
1003 }
1004 
lookup_module_symbol_name(unsigned long addr,char * symname)1005 static inline int lookup_module_symbol_name(unsigned long addr, char *symname)
1006 {
1007 	return -ERANGE;
1008 }
1009 
module_get_kallsym(unsigned int symnum,unsigned long * value,char * type,char * name,char * module_name,int * exported)1010 static inline int module_get_kallsym(unsigned int symnum, unsigned long *value,
1011 				     char *type, char *name,
1012 				     char *module_name, int *exported)
1013 {
1014 	return -ERANGE;
1015 }
1016 
module_kallsyms_lookup_name(const char * name)1017 static inline unsigned long module_kallsyms_lookup_name(const char *name)
1018 {
1019 	return 0;
1020 }
1021 
find_kallsyms_symbol_value(struct module * mod,const char * name)1022 static inline unsigned long find_kallsyms_symbol_value(struct module *mod,
1023 						       const char *name)
1024 {
1025 	return 0;
1026 }
1027 
1028 #endif  /* CONFIG_MODULES && CONFIG_KALLSYMS */
1029 
1030 #endif /* _LINUX_MODULE_H */
1031