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)(struct module_attribute *, struct module_kobject *,
56 char *);
57 ssize_t (*store)(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(struct module_attribute *,
71 struct module_kobject *, char *);
72
73 extern 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 * 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 #ifdef MODULE
242 /* Creates an alias so file2alias.c can find device table. */
243 #define MODULE_DEVICE_TABLE(type, name) \
244 extern typeof(name) __mod_##type##__##name##_device_table \
245 __attribute__ ((unused, alias(__stringify(name))))
246 #else /* !MODULE */
247 #define MODULE_DEVICE_TABLE(type, name)
248 #endif
249
250 /* Version of form [<epoch>:]<version>[-<extra-version>].
251 * Or for CVS/RCS ID version, everything but the number is stripped.
252 * <epoch>: A (small) unsigned integer which allows you to start versions
253 * anew. If not mentioned, it's zero. eg. "2:1.0" is after
254 * "1:2.0".
255
256 * <version>: The <version> may contain only alphanumerics and the
257 * character `.'. Ordered by numeric sort for numeric parts,
258 * ascii sort for ascii parts (as per RPM or DEB algorithm).
259
260 * <extraversion>: Like <version>, but inserted for local
261 * customizations, eg "rh3" or "rusty1".
262
263 * Using this automatically adds a checksum of the .c files and the
264 * local headers in "srcversion".
265 */
266
267 #if defined(MODULE) || !defined(CONFIG_SYSFS)
268 #define MODULE_VERSION(_version) MODULE_INFO(version, _version)
269 #else
270 #define MODULE_VERSION(_version) \
271 MODULE_INFO(version, _version); \
272 static struct module_version_attribute __modver_attr \
273 __used __section("__modver") \
274 __aligned(__alignof__(struct module_version_attribute)) \
275 = { \
276 .mattr = { \
277 .attr = { \
278 .name = "version", \
279 .mode = S_IRUGO, \
280 }, \
281 .show = __modver_version_show, \
282 }, \
283 .module_name = KBUILD_MODNAME, \
284 .version = _version, \
285 }
286 #endif
287
288 /* Optional firmware file (or files) needed by the module
289 * format is simply firmware file name. Multiple firmware
290 * files require multiple MODULE_FIRMWARE() specifiers */
291 #define MODULE_FIRMWARE(_firmware) MODULE_INFO(firmware, _firmware)
292
293 #define MODULE_IMPORT_NS(ns) MODULE_INFO(import_ns, __stringify(ns))
294
295 struct notifier_block;
296
297 #ifdef CONFIG_MODULES
298
299 extern int modules_disabled; /* for sysctl */
300 /* Get/put a kernel symbol (calls must be symmetric) */
301 void *__symbol_get(const char *symbol);
302 void *__symbol_get_gpl(const char *symbol);
303 #define symbol_get(x) ((typeof(&x))(__symbol_get(__stringify(x))))
304
305 /* modules using other modules: kdb wants to see this. */
306 struct module_use {
307 struct list_head source_list;
308 struct list_head target_list;
309 struct module *source, *target;
310 };
311
312 enum module_state {
313 MODULE_STATE_LIVE, /* Normal state. */
314 MODULE_STATE_COMING, /* Full formed, running module_init. */
315 MODULE_STATE_GOING, /* Going away. */
316 MODULE_STATE_UNFORMED, /* Still setting it up. */
317 };
318
319 struct mod_tree_node {
320 struct module *mod;
321 struct latch_tree_node node;
322 };
323
324 enum mod_mem_type {
325 MOD_TEXT = 0,
326 MOD_DATA,
327 MOD_RODATA,
328 MOD_RO_AFTER_INIT,
329 MOD_INIT_TEXT,
330 MOD_INIT_DATA,
331 MOD_INIT_RODATA,
332
333 MOD_MEM_NUM_TYPES,
334 MOD_INVALID = -1,
335 };
336
337 #define mod_mem_type_is_init(type) \
338 ((type) == MOD_INIT_TEXT || \
339 (type) == MOD_INIT_DATA || \
340 (type) == MOD_INIT_RODATA)
341
342 #define mod_mem_type_is_core(type) (!mod_mem_type_is_init(type))
343
344 #define mod_mem_type_is_text(type) \
345 ((type) == MOD_TEXT || \
346 (type) == MOD_INIT_TEXT)
347
348 #define mod_mem_type_is_data(type) (!mod_mem_type_is_text(type))
349
350 #define mod_mem_type_is_core_data(type) \
351 (mod_mem_type_is_core(type) && \
352 mod_mem_type_is_data(type))
353
354 #define for_each_mod_mem_type(type) \
355 for (enum mod_mem_type (type) = 0; \
356 (type) < MOD_MEM_NUM_TYPES; (type)++)
357
358 #define for_class_mod_mem_type(type, class) \
359 for_each_mod_mem_type(type) \
360 if (mod_mem_type_is_##class(type))
361
362 struct module_memory {
363 void *base;
364 unsigned int size;
365
366 #ifdef CONFIG_MODULES_TREE_LOOKUP
367 struct mod_tree_node mtn;
368 #endif
369 };
370
371 #ifdef CONFIG_MODULES_TREE_LOOKUP
372 /* Only touch one cacheline for common rbtree-for-core-layout case. */
373 #define __module_memory_align ____cacheline_aligned
374 #else
375 #define __module_memory_align
376 #endif
377
378 struct mod_kallsyms {
379 Elf_Sym *symtab;
380 unsigned int num_symtab;
381 char *strtab;
382 char *typetab;
383 };
384
385 #ifdef CONFIG_LIVEPATCH
386 /**
387 * struct klp_modinfo - ELF information preserved from the livepatch module
388 *
389 * @hdr: ELF header
390 * @sechdrs: Section header table
391 * @secstrings: String table for the section headers
392 * @symndx: The symbol table section index
393 */
394 struct klp_modinfo {
395 Elf_Ehdr hdr;
396 Elf_Shdr *sechdrs;
397 char *secstrings;
398 unsigned int symndx;
399 };
400 #endif
401
402 struct module {
403 enum module_state state;
404
405 /* Member of list of modules */
406 struct list_head list;
407
408 /* Unique handle for this module */
409 char name[MODULE_NAME_LEN];
410
411 #ifdef CONFIG_STACKTRACE_BUILD_ID
412 /* Module build ID */
413 unsigned char build_id[BUILD_ID_SIZE_MAX];
414 #endif
415
416 /* Sysfs stuff. */
417 struct module_kobject mkobj;
418 struct module_attribute *modinfo_attrs;
419 const char *version;
420 const char *srcversion;
421 struct kobject *holders_dir;
422
423 /* Exported symbols */
424 const struct kernel_symbol *syms;
425 const s32 *crcs;
426 unsigned int num_syms;
427
428 #ifdef CONFIG_ARCH_USES_CFI_TRAPS
429 s32 *kcfi_traps;
430 s32 *kcfi_traps_end;
431 #endif
432
433 /* Kernel parameters. */
434 #ifdef CONFIG_SYSFS
435 struct mutex param_lock;
436 #endif
437 struct kernel_param *kp;
438 unsigned int num_kp;
439
440 /* GPL-only exported symbols. */
441 unsigned int num_gpl_syms;
442 const struct kernel_symbol *gpl_syms;
443 const s32 *gpl_crcs;
444 bool using_gplonly_symbols;
445
446 #ifdef CONFIG_MODULE_SIG
447 /* Signature was verified. */
448 bool sig_ok;
449 #endif
450
451 bool async_probe_requested;
452
453 /* Exception table */
454 unsigned int num_exentries;
455 struct exception_table_entry *extable;
456
457 /* Startup function. */
458 int (*init)(void);
459
460 struct module_memory mem[MOD_MEM_NUM_TYPES] __module_memory_align;
461
462 /* Arch-specific module values */
463 struct mod_arch_specific arch;
464
465 unsigned long taints; /* same bits as kernel:taint_flags */
466
467 #ifdef CONFIG_GENERIC_BUG
468 /* Support for BUG */
469 unsigned num_bugs;
470 struct list_head bug_list;
471 struct bug_entry *bug_table;
472 #endif
473
474 #ifdef CONFIG_KALLSYMS
475 /* Protected by RCU and/or module_mutex: use rcu_dereference() */
476 struct mod_kallsyms __rcu *kallsyms;
477 struct mod_kallsyms core_kallsyms;
478
479 /* Section attributes */
480 struct module_sect_attrs *sect_attrs;
481
482 /* Notes attributes */
483 struct module_notes_attrs *notes_attrs;
484 #endif
485
486 /* The command line arguments (may be mangled). People like
487 keeping pointers to this stuff */
488 char *args;
489
490 #ifdef CONFIG_SMP
491 /* Per-cpu data. */
492 void __percpu *percpu;
493 unsigned int percpu_size;
494 #endif
495 void *noinstr_text_start;
496 unsigned int noinstr_text_size;
497
498 #ifdef CONFIG_TRACEPOINTS
499 unsigned int num_tracepoints;
500 tracepoint_ptr_t *tracepoints_ptrs;
501 #endif
502 #ifdef CONFIG_TREE_SRCU
503 unsigned int num_srcu_structs;
504 struct srcu_struct **srcu_struct_ptrs;
505 #endif
506 #ifdef CONFIG_BPF_EVENTS
507 unsigned int num_bpf_raw_events;
508 struct bpf_raw_event_map *bpf_raw_events;
509 #endif
510 #ifdef CONFIG_DEBUG_INFO_BTF_MODULES
511 unsigned int btf_data_size;
512 void *btf_data;
513 #endif
514 #ifdef CONFIG_JUMP_LABEL
515 struct jump_entry *jump_entries;
516 unsigned int num_jump_entries;
517 #endif
518 #ifdef CONFIG_TRACING
519 unsigned int num_trace_bprintk_fmt;
520 const char **trace_bprintk_fmt_start;
521 #endif
522 #ifdef CONFIG_EVENT_TRACING
523 struct trace_event_call **trace_events;
524 unsigned int num_trace_events;
525 struct trace_eval_map **trace_evals;
526 unsigned int num_trace_evals;
527 #endif
528 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
529 unsigned int num_ftrace_callsites;
530 unsigned long *ftrace_callsites;
531 #endif
532 #ifdef CONFIG_KPROBES
533 void *kprobes_text_start;
534 unsigned int kprobes_text_size;
535 unsigned long *kprobe_blacklist;
536 unsigned int num_kprobe_blacklist;
537 #endif
538 #ifdef CONFIG_HAVE_STATIC_CALL_INLINE
539 int num_static_call_sites;
540 struct static_call_site *static_call_sites;
541 #endif
542 #if IS_ENABLED(CONFIG_KUNIT)
543 int num_kunit_init_suites;
544 struct kunit_suite **kunit_init_suites;
545 int num_kunit_suites;
546 struct kunit_suite **kunit_suites;
547 #endif
548
549
550 #ifdef CONFIG_LIVEPATCH
551 bool klp; /* Is this a livepatch module? */
552 bool klp_alive;
553
554 /* ELF information */
555 struct klp_modinfo *klp_info;
556 #endif
557
558 #ifdef CONFIG_PRINTK_INDEX
559 unsigned int printk_index_size;
560 struct pi_entry **printk_index_start;
561 #endif
562
563 #ifdef CONFIG_MODULE_UNLOAD
564 /* What modules depend on me? */
565 struct list_head source_list;
566 /* What modules do I depend on? */
567 struct list_head target_list;
568
569 /* Destruction function. */
570 void (*exit)(void);
571
572 atomic_t refcnt;
573 #endif
574
575 #ifdef CONFIG_CONSTRUCTORS
576 /* Constructor functions. */
577 ctor_fn_t *ctors;
578 unsigned int num_ctors;
579 #endif
580
581 #ifdef CONFIG_FUNCTION_ERROR_INJECTION
582 struct error_injection_entry *ei_funcs;
583 unsigned int num_ei_funcs;
584 #endif
585 #ifdef CONFIG_DYNAMIC_DEBUG_CORE
586 struct _ddebug_info dyndbg_info;
587 #endif
588 } ____cacheline_aligned __randomize_layout;
589 #ifndef MODULE_ARCH_INIT
590 #define MODULE_ARCH_INIT {}
591 #endif
592
593 #ifndef HAVE_ARCH_KALLSYMS_SYMBOL_VALUE
kallsyms_symbol_value(const Elf_Sym * sym)594 static inline unsigned long kallsyms_symbol_value(const Elf_Sym *sym)
595 {
596 return sym->st_value;
597 }
598 #endif
599
600 /* FIXME: It'd be nice to isolate modules during init, too, so they
601 aren't used before they (may) fail. But presently too much code
602 (IDE & SCSI) require entry into the module during init.*/
module_is_live(struct module * mod)603 static inline bool module_is_live(struct module *mod)
604 {
605 return mod->state != MODULE_STATE_GOING;
606 }
607
module_is_coming(struct module * mod)608 static inline bool module_is_coming(struct module *mod)
609 {
610 return mod->state == MODULE_STATE_COMING;
611 }
612
613 struct module *__module_text_address(unsigned long addr);
614 struct module *__module_address(unsigned long addr);
615 bool is_module_address(unsigned long addr);
616 bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr);
617 bool is_module_percpu_address(unsigned long addr);
618 bool is_module_text_address(unsigned long addr);
619
within_module_mem_type(unsigned long addr,const struct module * mod,enum mod_mem_type type)620 static inline bool within_module_mem_type(unsigned long addr,
621 const struct module *mod,
622 enum mod_mem_type type)
623 {
624 unsigned long base, size;
625
626 base = (unsigned long)mod->mem[type].base;
627 size = mod->mem[type].size;
628 return addr - base < size;
629 }
630
within_module_core(unsigned long addr,const struct module * mod)631 static inline bool within_module_core(unsigned long addr,
632 const struct module *mod)
633 {
634 for_class_mod_mem_type(type, core) {
635 if (within_module_mem_type(addr, mod, type))
636 return true;
637 }
638 return false;
639 }
640
within_module_init(unsigned long addr,const struct module * mod)641 static inline bool within_module_init(unsigned long addr,
642 const struct module *mod)
643 {
644 for_class_mod_mem_type(type, init) {
645 if (within_module_mem_type(addr, mod, type))
646 return true;
647 }
648 return false;
649 }
650
within_module(unsigned long addr,const struct module * mod)651 static inline bool within_module(unsigned long addr, const struct module *mod)
652 {
653 return within_module_init(addr, mod) || within_module_core(addr, mod);
654 }
655
656 /* Search for module by name: must be in a RCU-sched critical section. */
657 struct module *find_module(const char *name);
658
659 extern void __noreturn __module_put_and_kthread_exit(struct module *mod,
660 long code);
661 #define module_put_and_kthread_exit(code) __module_put_and_kthread_exit(THIS_MODULE, code)
662
663 #ifdef CONFIG_MODULE_UNLOAD
664 int module_refcount(struct module *mod);
665 void __symbol_put(const char *symbol);
666 #define symbol_put(x) __symbol_put(__stringify(x))
667 void symbol_put_addr(void *addr);
668
669 /* Sometimes we know we already have a refcount, and it's easier not
670 to handle the error case (which only happens with rmmod --wait). */
671 extern void __module_get(struct module *module);
672
673 /**
674 * try_module_get() - take module refcount unless module is being removed
675 * @module: the module we should check for
676 *
677 * Only try to get a module reference count if the module is not being removed.
678 * This call will fail if the module is in the process of being removed.
679 *
680 * Care must also be taken to ensure the module exists and is alive prior to
681 * usage of this call. This can be gauranteed through two means:
682 *
683 * 1) Direct protection: you know an earlier caller must have increased the
684 * module reference through __module_get(). This can typically be achieved
685 * by having another entity other than the module itself increment the
686 * module reference count.
687 *
688 * 2) Implied protection: there is an implied protection against module
689 * removal. An example of this is the implied protection used by kernfs /
690 * sysfs. The sysfs store / read file operations are guaranteed to exist
691 * through the use of kernfs's active reference (see kernfs_active()) and a
692 * sysfs / kernfs file removal cannot happen unless the same file is not
693 * active. Therefore, if a sysfs file is being read or written to the module
694 * which created it must still exist. It is therefore safe to use
695 * try_module_get() on module sysfs store / read ops.
696 *
697 * One of the real values to try_module_get() is the module_is_live() check
698 * which ensures that the caller of try_module_get() can yield to userspace
699 * module removal requests and gracefully fail if the module is on its way out.
700 *
701 * Returns true if the reference count was successfully incremented.
702 */
703 extern bool try_module_get(struct module *module);
704
705 /**
706 * module_put() - release a reference count to a module
707 * @module: the module we should release a reference count for
708 *
709 * If you successfully bump a reference count to a module with try_module_get(),
710 * when you are finished you must call module_put() to release that reference
711 * count.
712 */
713 extern void module_put(struct module *module);
714
715 #else /*!CONFIG_MODULE_UNLOAD*/
try_module_get(struct module * module)716 static inline bool try_module_get(struct module *module)
717 {
718 return !module || module_is_live(module);
719 }
module_put(struct module * module)720 static inline void module_put(struct module *module)
721 {
722 }
__module_get(struct module * module)723 static inline void __module_get(struct module *module)
724 {
725 }
726 #define symbol_put(x) do { } while (0)
727 #define symbol_put_addr(p) do { } while (0)
728
729 #endif /* CONFIG_MODULE_UNLOAD */
730
731 /* This is a #define so the string doesn't get put in every .o file */
732 #define module_name(mod) \
733 ({ \
734 struct module *__mod = (mod); \
735 __mod ? __mod->name : "kernel"; \
736 })
737
738 /* Dereference module function descriptor */
739 void *dereference_module_function_descriptor(struct module *mod, void *ptr);
740
741 int register_module_notifier(struct notifier_block *nb);
742 int unregister_module_notifier(struct notifier_block *nb);
743
744 extern void print_modules(void);
745
module_requested_async_probing(struct module * module)746 static inline bool module_requested_async_probing(struct module *module)
747 {
748 return module && module->async_probe_requested;
749 }
750
is_livepatch_module(struct module * mod)751 static inline bool is_livepatch_module(struct module *mod)
752 {
753 #ifdef CONFIG_LIVEPATCH
754 return mod->klp;
755 #else
756 return false;
757 #endif
758 }
759
760 void set_module_sig_enforced(void);
761
762 #else /* !CONFIG_MODULES... */
763
__module_address(unsigned long addr)764 static inline struct module *__module_address(unsigned long addr)
765 {
766 return NULL;
767 }
768
__module_text_address(unsigned long addr)769 static inline struct module *__module_text_address(unsigned long addr)
770 {
771 return NULL;
772 }
773
is_module_address(unsigned long addr)774 static inline bool is_module_address(unsigned long addr)
775 {
776 return false;
777 }
778
is_module_percpu_address(unsigned long addr)779 static inline bool is_module_percpu_address(unsigned long addr)
780 {
781 return false;
782 }
783
__is_module_percpu_address(unsigned long addr,unsigned long * can_addr)784 static inline bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr)
785 {
786 return false;
787 }
788
is_module_text_address(unsigned long addr)789 static inline bool is_module_text_address(unsigned long addr)
790 {
791 return false;
792 }
793
within_module_core(unsigned long addr,const struct module * mod)794 static inline bool within_module_core(unsigned long addr,
795 const struct module *mod)
796 {
797 return false;
798 }
799
within_module_init(unsigned long addr,const struct module * mod)800 static inline bool within_module_init(unsigned long addr,
801 const struct module *mod)
802 {
803 return false;
804 }
805
within_module(unsigned long addr,const struct module * mod)806 static inline bool within_module(unsigned long addr, const struct module *mod)
807 {
808 return false;
809 }
810
811 /* Get/put a kernel symbol (calls should be symmetric) */
812 #define symbol_get(x) ({ extern typeof(x) x __attribute__((weak,visibility("hidden"))); &(x); })
813 #define symbol_put(x) do { } while (0)
814 #define symbol_put_addr(x) do { } while (0)
815
__module_get(struct module * module)816 static inline void __module_get(struct module *module)
817 {
818 }
819
try_module_get(struct module * module)820 static inline bool try_module_get(struct module *module)
821 {
822 return true;
823 }
824
module_put(struct module * module)825 static inline void module_put(struct module *module)
826 {
827 }
828
829 #define module_name(mod) "kernel"
830
register_module_notifier(struct notifier_block * nb)831 static inline int register_module_notifier(struct notifier_block *nb)
832 {
833 /* no events will happen anyway, so this can always succeed */
834 return 0;
835 }
836
unregister_module_notifier(struct notifier_block * nb)837 static inline int unregister_module_notifier(struct notifier_block *nb)
838 {
839 return 0;
840 }
841
842 #define module_put_and_kthread_exit(code) kthread_exit(code)
843
print_modules(void)844 static inline void print_modules(void)
845 {
846 }
847
module_requested_async_probing(struct module * module)848 static inline bool module_requested_async_probing(struct module *module)
849 {
850 return false;
851 }
852
853
set_module_sig_enforced(void)854 static inline void set_module_sig_enforced(void)
855 {
856 }
857
858 /* Dereference module function descriptor */
859 static inline
dereference_module_function_descriptor(struct module * mod,void * ptr)860 void *dereference_module_function_descriptor(struct module *mod, void *ptr)
861 {
862 return ptr;
863 }
864
module_is_coming(struct module * mod)865 static inline bool module_is_coming(struct module *mod)
866 {
867 return false;
868 }
869 #endif /* CONFIG_MODULES */
870
871 #ifdef CONFIG_SYSFS
872 extern struct kset *module_kset;
873 extern const struct kobj_type module_ktype;
874 #endif /* CONFIG_SYSFS */
875
876 #define symbol_request(x) try_then_request_module(symbol_get(x), "symbol:" #x)
877
878 /* BELOW HERE ALL THESE ARE OBSOLETE AND WILL VANISH */
879
880 #define __MODULE_STRING(x) __stringify(x)
881
882 #ifdef CONFIG_GENERIC_BUG
883 void module_bug_finalize(const Elf_Ehdr *, const Elf_Shdr *,
884 struct module *);
885 void module_bug_cleanup(struct module *);
886
887 #else /* !CONFIG_GENERIC_BUG */
888
module_bug_finalize(const Elf_Ehdr * hdr,const Elf_Shdr * sechdrs,struct module * mod)889 static inline void module_bug_finalize(const Elf_Ehdr *hdr,
890 const Elf_Shdr *sechdrs,
891 struct module *mod)
892 {
893 }
module_bug_cleanup(struct module * mod)894 static inline void module_bug_cleanup(struct module *mod) {}
895 #endif /* CONFIG_GENERIC_BUG */
896
897 #ifdef CONFIG_MITIGATION_RETPOLINE
898 extern bool retpoline_module_ok(bool has_retpoline);
899 #else
retpoline_module_ok(bool has_retpoline)900 static inline bool retpoline_module_ok(bool has_retpoline)
901 {
902 return true;
903 }
904 #endif
905
906 #ifdef CONFIG_MODULE_SIG
907 bool is_module_sig_enforced(void);
908
module_sig_ok(struct module * module)909 static inline bool module_sig_ok(struct module *module)
910 {
911 return module->sig_ok;
912 }
913 #else /* !CONFIG_MODULE_SIG */
is_module_sig_enforced(void)914 static inline bool is_module_sig_enforced(void)
915 {
916 return false;
917 }
918
module_sig_ok(struct module * module)919 static inline bool module_sig_ok(struct module *module)
920 {
921 return true;
922 }
923 #endif /* CONFIG_MODULE_SIG */
924
925 #if defined(CONFIG_MODULES) && defined(CONFIG_KALLSYMS)
926 int module_kallsyms_on_each_symbol(const char *modname,
927 int (*fn)(void *, const char *, unsigned long),
928 void *data);
929
930 /* For kallsyms to ask for address resolution. namebuf should be at
931 * least KSYM_NAME_LEN long: a pointer to namebuf is returned if
932 * found, otherwise NULL.
933 */
934 const char *module_address_lookup(unsigned long addr,
935 unsigned long *symbolsize,
936 unsigned long *offset,
937 char **modname, const unsigned char **modbuildid,
938 char *namebuf);
939 int lookup_module_symbol_name(unsigned long addr, char *symname);
940 int lookup_module_symbol_attrs(unsigned long addr,
941 unsigned long *size,
942 unsigned long *offset,
943 char *modname,
944 char *name);
945
946 /* Returns 0 and fills in value, defined and namebuf, or -ERANGE if
947 * symnum out of range.
948 */
949 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
950 char *name, char *module_name, int *exported);
951
952 /* Look for this name: can be of form module:name. */
953 unsigned long module_kallsyms_lookup_name(const char *name);
954
955 unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name);
956
957 #else /* CONFIG_MODULES && CONFIG_KALLSYMS */
958
module_kallsyms_on_each_symbol(const char * modname,int (* fn)(void *,const char *,unsigned long),void * data)959 static inline int module_kallsyms_on_each_symbol(const char *modname,
960 int (*fn)(void *, const char *, unsigned long),
961 void *data)
962 {
963 return -EOPNOTSUPP;
964 }
965
966 /* 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)967 static inline const char *module_address_lookup(unsigned long addr,
968 unsigned long *symbolsize,
969 unsigned long *offset,
970 char **modname,
971 const unsigned char **modbuildid,
972 char *namebuf)
973 {
974 return NULL;
975 }
976
lookup_module_symbol_name(unsigned long addr,char * symname)977 static inline int lookup_module_symbol_name(unsigned long addr, char *symname)
978 {
979 return -ERANGE;
980 }
981
module_get_kallsym(unsigned int symnum,unsigned long * value,char * type,char * name,char * module_name,int * exported)982 static inline int module_get_kallsym(unsigned int symnum, unsigned long *value,
983 char *type, char *name,
984 char *module_name, int *exported)
985 {
986 return -ERANGE;
987 }
988
module_kallsyms_lookup_name(const char * name)989 static inline unsigned long module_kallsyms_lookup_name(const char *name)
990 {
991 return 0;
992 }
993
find_kallsyms_symbol_value(struct module * mod,const char * name)994 static inline unsigned long find_kallsyms_symbol_value(struct module *mod,
995 const char *name)
996 {
997 return 0;
998 }
999
1000 #endif /* CONFIG_MODULES && CONFIG_KALLSYMS */
1001
1002 #endif /* _LINUX_MODULE_H */
1003