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 #define __INIT_OR_MODULE .text
155 #define __INITDATA_OR_MODULE .data
156 #define __INITRODATA_OR_MODULE .section ".rodata","a",%progbits
157 #else
158 #define __init_or_module __init
159 #define __initdata_or_module __initdata
160 #define __initconst_or_module __initconst
161 #define __INIT_OR_MODULE __INIT
162 #define __INITDATA_OR_MODULE __INITDATA
163 #define __INITRODATA_OR_MODULE __INITRODATA
164 #endif /*CONFIG_MODULES*/
165
166 struct module_kobject *lookup_or_create_module_kobject(const char *name);
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 static typeof(name) __mod_device_table__##type##__##name \
251 __attribute__ ((used, 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 enum module_state {
304 MODULE_STATE_LIVE, /* Normal state. */
305 MODULE_STATE_COMING, /* Full formed, running module_init. */
306 MODULE_STATE_GOING, /* Going away. */
307 MODULE_STATE_UNFORMED, /* Still setting it up. */
308 };
309
310 struct mod_tree_node {
311 struct module *mod;
312 struct latch_tree_node node;
313 };
314
315 enum mod_mem_type {
316 MOD_TEXT = 0,
317 MOD_DATA,
318 MOD_RODATA,
319 MOD_RO_AFTER_INIT,
320 MOD_INIT_TEXT,
321 MOD_INIT_DATA,
322 MOD_INIT_RODATA,
323
324 MOD_MEM_NUM_TYPES,
325 MOD_INVALID = -1,
326 };
327
328 #define mod_mem_type_is_init(type) \
329 ((type) == MOD_INIT_TEXT || \
330 (type) == MOD_INIT_DATA || \
331 (type) == MOD_INIT_RODATA)
332
333 #define mod_mem_type_is_core(type) (!mod_mem_type_is_init(type))
334
335 #define mod_mem_type_is_text(type) \
336 ((type) == MOD_TEXT || \
337 (type) == MOD_INIT_TEXT)
338
339 #define mod_mem_type_is_data(type) (!mod_mem_type_is_text(type))
340
341 #define mod_mem_type_is_core_data(type) \
342 (mod_mem_type_is_core(type) && \
343 mod_mem_type_is_data(type))
344
345 #define for_each_mod_mem_type(type) \
346 for (enum mod_mem_type (type) = 0; \
347 (type) < MOD_MEM_NUM_TYPES; (type)++)
348
349 #define for_class_mod_mem_type(type, class) \
350 for_each_mod_mem_type(type) \
351 if (mod_mem_type_is_##class(type))
352
353 struct module_memory {
354 void *base;
355 bool is_rox;
356 unsigned int size;
357
358 #ifdef CONFIG_MODULES_TREE_LOOKUP
359 struct mod_tree_node mtn;
360 #endif
361 };
362
363 #ifdef CONFIG_MODULES_TREE_LOOKUP
364 /* Only touch one cacheline for common rbtree-for-core-layout case. */
365 #define __module_memory_align ____cacheline_aligned
366 #else
367 #define __module_memory_align
368 #endif
369
370 struct mod_kallsyms {
371 Elf_Sym *symtab;
372 unsigned int num_symtab;
373 char *strtab;
374 char *typetab;
375 };
376
377 #ifdef CONFIG_LIVEPATCH
378 /**
379 * struct klp_modinfo - ELF information preserved from the livepatch module
380 *
381 * @hdr: ELF header
382 * @sechdrs: Section header table
383 * @secstrings: String table for the section headers
384 * @symndx: The symbol table section index
385 */
386 struct klp_modinfo {
387 Elf_Ehdr hdr;
388 Elf_Shdr *sechdrs;
389 char *secstrings;
390 unsigned int symndx;
391 };
392 #endif
393
394 struct module {
395 enum module_state state;
396
397 /* Member of list of modules */
398 struct list_head list;
399
400 /* Unique handle for this module */
401 char name[MODULE_NAME_LEN];
402
403 #ifdef CONFIG_STACKTRACE_BUILD_ID
404 /* Module build ID */
405 unsigned char build_id[BUILD_ID_SIZE_MAX];
406 #endif
407
408 /* Sysfs stuff. */
409 struct module_kobject mkobj;
410 struct module_attribute *modinfo_attrs;
411 const char *version;
412 const char *srcversion;
413 struct kobject *holders_dir;
414
415 /* Exported symbols */
416 const struct kernel_symbol *syms;
417 const u32 *crcs;
418 unsigned int num_syms;
419
420 #ifdef CONFIG_ARCH_USES_CFI_TRAPS
421 s32 *kcfi_traps;
422 s32 *kcfi_traps_end;
423 #endif
424
425 /* Kernel parameters. */
426 #ifdef CONFIG_SYSFS
427 struct mutex param_lock;
428 #endif
429 struct kernel_param *kp;
430 unsigned int num_kp;
431
432 /* GPL-only exported symbols. */
433 unsigned int num_gpl_syms;
434 const struct kernel_symbol *gpl_syms;
435 const u32 *gpl_crcs;
436 bool using_gplonly_symbols;
437
438 #ifdef CONFIG_MODULE_SIG
439 /* Signature was verified. */
440 bool sig_ok;
441 #endif
442
443 bool async_probe_requested;
444
445 /* Exception table */
446 unsigned int num_exentries;
447 struct exception_table_entry *extable;
448
449 /* Startup function. */
450 int (*init)(void);
451
452 struct module_memory mem[MOD_MEM_NUM_TYPES] __module_memory_align;
453
454 /* Arch-specific module values */
455 struct mod_arch_specific arch;
456
457 unsigned long taints; /* same bits as kernel:taint_flags */
458
459 #ifdef CONFIG_GENERIC_BUG
460 /* Support for BUG */
461 unsigned num_bugs;
462 struct list_head bug_list;
463 struct bug_entry *bug_table;
464 #endif
465
466 #ifdef CONFIG_KALLSYMS
467 /* Protected by RCU and/or module_mutex: use rcu_dereference() */
468 struct mod_kallsyms __rcu *kallsyms;
469 struct mod_kallsyms core_kallsyms;
470
471 /* Section attributes */
472 struct module_sect_attrs *sect_attrs;
473
474 /* Notes attributes */
475 struct module_notes_attrs *notes_attrs;
476 #endif
477
478 /* The command line arguments (may be mangled). People like
479 keeping pointers to this stuff */
480 char *args;
481
482 #ifdef CONFIG_SMP
483 /* Per-cpu data. */
484 void __percpu *percpu;
485 unsigned int percpu_size;
486 #endif
487 void *noinstr_text_start;
488 unsigned int noinstr_text_size;
489
490 #ifdef CONFIG_TRACEPOINTS
491 unsigned int num_tracepoints;
492 tracepoint_ptr_t *tracepoints_ptrs;
493 #endif
494 #ifdef CONFIG_TREE_SRCU
495 unsigned int num_srcu_structs;
496 struct srcu_struct **srcu_struct_ptrs;
497 #endif
498 #ifdef CONFIG_BPF_EVENTS
499 unsigned int num_bpf_raw_events;
500 struct bpf_raw_event_map *bpf_raw_events;
501 #endif
502 #ifdef CONFIG_DEBUG_INFO_BTF_MODULES
503 unsigned int btf_data_size;
504 unsigned int btf_base_data_size;
505 void *btf_data;
506 void *btf_base_data;
507 #endif
508 #ifdef CONFIG_JUMP_LABEL
509 struct jump_entry *jump_entries;
510 unsigned int num_jump_entries;
511 #endif
512 #ifdef CONFIG_TRACING
513 unsigned int num_trace_bprintk_fmt;
514 const char **trace_bprintk_fmt_start;
515 #endif
516 #ifdef CONFIG_EVENT_TRACING
517 struct trace_event_call **trace_events;
518 unsigned int num_trace_events;
519 struct trace_eval_map **trace_evals;
520 unsigned int num_trace_evals;
521 #endif
522 #ifdef CONFIG_DYNAMIC_FTRACE
523 unsigned int num_ftrace_callsites;
524 unsigned long *ftrace_callsites;
525 #endif
526 #ifdef CONFIG_KPROBES
527 void *kprobes_text_start;
528 unsigned int kprobes_text_size;
529 unsigned long *kprobe_blacklist;
530 unsigned int num_kprobe_blacklist;
531 #endif
532 #ifdef CONFIG_HAVE_STATIC_CALL_INLINE
533 int num_static_call_sites;
534 struct static_call_site *static_call_sites;
535 #endif
536 #if IS_ENABLED(CONFIG_KUNIT)
537 int num_kunit_init_suites;
538 struct kunit_suite **kunit_init_suites;
539 int num_kunit_suites;
540 struct kunit_suite **kunit_suites;
541 #endif
542
543
544 #ifdef CONFIG_LIVEPATCH
545 bool klp; /* Is this a livepatch module? */
546 bool klp_alive;
547
548 /* ELF information */
549 struct klp_modinfo *klp_info;
550 #endif
551
552 #ifdef CONFIG_PRINTK_INDEX
553 unsigned int printk_index_size;
554 struct pi_entry **printk_index_start;
555 #endif
556
557 #ifdef CONFIG_MODULE_UNLOAD
558 /* What modules depend on me? */
559 struct list_head source_list;
560 /* What modules do I depend on? */
561 struct list_head target_list;
562
563 /* Destruction function. */
564 void (*exit)(void);
565
566 atomic_t refcnt;
567 #endif
568
569 #ifdef CONFIG_CONSTRUCTORS
570 /* Constructor functions. */
571 ctor_fn_t *ctors;
572 unsigned int num_ctors;
573 #endif
574
575 #ifdef CONFIG_FUNCTION_ERROR_INJECTION
576 struct error_injection_entry *ei_funcs;
577 unsigned int num_ei_funcs;
578 #endif
579 #ifdef CONFIG_DYNAMIC_DEBUG_CORE
580 struct _ddebug_info dyndbg_info;
581 #endif
582 } ____cacheline_aligned __randomize_layout;
583 #ifndef MODULE_ARCH_INIT
584 #define MODULE_ARCH_INIT {}
585 #endif
586
587 #ifdef CONFIG_MODULES
588
589 /* Get/put a kernel symbol (calls must be symmetric) */
590 void *__symbol_get(const char *symbol);
591 void *__symbol_get_gpl(const char *symbol);
592 #define symbol_get(x) ({ \
593 static const char __notrim[] \
594 __used __section(".no_trim_symbol") = __stringify(x); \
595 (typeof(&x))(__symbol_get(__stringify(x))); })
596
597 #ifndef HAVE_ARCH_KALLSYMS_SYMBOL_VALUE
kallsyms_symbol_value(const Elf_Sym * sym)598 static inline unsigned long kallsyms_symbol_value(const Elf_Sym *sym)
599 {
600 return sym->st_value;
601 }
602 #endif
603
604 /* FIXME: It'd be nice to isolate modules during init, too, so they
605 aren't used before they (may) fail. But presently too much code
606 (IDE & SCSI) require entry into the module during init.*/
module_is_live(struct module * mod)607 static inline bool module_is_live(struct module *mod)
608 {
609 return mod->state != MODULE_STATE_GOING;
610 }
611
module_is_coming(struct module * mod)612 static inline bool module_is_coming(struct module *mod)
613 {
614 return mod->state == MODULE_STATE_COMING;
615 }
616
617 struct module *__module_text_address(unsigned long addr);
618 struct module *__module_address(unsigned long addr);
619 bool is_module_address(unsigned long addr);
620 bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr);
621 bool is_module_percpu_address(unsigned long addr);
622 bool is_module_text_address(unsigned long addr);
623
within_module_mem_type(unsigned long addr,const struct module * mod,enum mod_mem_type type)624 static inline bool within_module_mem_type(unsigned long addr,
625 const struct module *mod,
626 enum mod_mem_type type)
627 {
628 unsigned long base, size;
629
630 base = (unsigned long)mod->mem[type].base;
631 size = mod->mem[type].size;
632 return addr - base < size;
633 }
634
within_module_core(unsigned long addr,const struct module * mod)635 static inline bool within_module_core(unsigned long addr,
636 const struct module *mod)
637 {
638 for_class_mod_mem_type(type, core) {
639 if (within_module_mem_type(addr, mod, type))
640 return true;
641 }
642 return false;
643 }
644
within_module_init(unsigned long addr,const struct module * mod)645 static inline bool within_module_init(unsigned long addr,
646 const struct module *mod)
647 {
648 for_class_mod_mem_type(type, init) {
649 if (within_module_mem_type(addr, mod, type))
650 return true;
651 }
652 return false;
653 }
654
within_module(unsigned long addr,const struct module * mod)655 static inline bool within_module(unsigned long addr, const struct module *mod)
656 {
657 return within_module_init(addr, mod) || within_module_core(addr, mod);
658 }
659
660 /* Search for module by name: must be in a RCU critical section. */
661 struct module *find_module(const char *name);
662
663 extern void __noreturn __module_put_and_kthread_exit(struct module *mod,
664 long code);
665 #define module_put_and_kthread_exit(code) __module_put_and_kthread_exit(THIS_MODULE, code)
666
667 #ifdef CONFIG_MODULE_UNLOAD
668 int module_refcount(struct module *mod);
669 void __symbol_put(const char *symbol);
670 #define symbol_put(x) __symbol_put(__stringify(x))
671 void symbol_put_addr(void *addr);
672
673 /* Sometimes we know we already have a refcount, and it's easier not
674 to handle the error case (which only happens with rmmod --wait). */
675 extern void __module_get(struct module *module);
676
677 /**
678 * try_module_get() - take module refcount unless module is being removed
679 * @module: the module we should check for
680 *
681 * Only try to get a module reference count if the module is not being removed.
682 * This call will fail if the module is in the process of being removed.
683 *
684 * Care must also be taken to ensure the module exists and is alive prior to
685 * usage of this call. This can be gauranteed through two means:
686 *
687 * 1) Direct protection: you know an earlier caller must have increased the
688 * module reference through __module_get(). This can typically be achieved
689 * by having another entity other than the module itself increment the
690 * module reference count.
691 *
692 * 2) Implied protection: there is an implied protection against module
693 * removal. An example of this is the implied protection used by kernfs /
694 * sysfs. The sysfs store / read file operations are guaranteed to exist
695 * through the use of kernfs's active reference (see kernfs_active()) and a
696 * sysfs / kernfs file removal cannot happen unless the same file is not
697 * active. Therefore, if a sysfs file is being read or written to the module
698 * which created it must still exist. It is therefore safe to use
699 * try_module_get() on module sysfs store / read ops.
700 *
701 * One of the real values to try_module_get() is the module_is_live() check
702 * which ensures that the caller of try_module_get() can yield to userspace
703 * module removal requests and gracefully fail if the module is on its way out.
704 *
705 * Returns true if the reference count was successfully incremented.
706 */
707 extern bool try_module_get(struct module *module);
708
709 /**
710 * module_put() - release a reference count to a module
711 * @module: the module we should release a reference count for
712 *
713 * If you successfully bump a reference count to a module with try_module_get(),
714 * when you are finished you must call module_put() to release that reference
715 * count.
716 */
717 extern void module_put(struct module *module);
718
719 #else /*!CONFIG_MODULE_UNLOAD*/
try_module_get(struct module * module)720 static inline bool try_module_get(struct module *module)
721 {
722 return !module || module_is_live(module);
723 }
module_put(struct module * module)724 static inline void module_put(struct module *module)
725 {
726 }
__module_get(struct module * module)727 static inline void __module_get(struct module *module)
728 {
729 }
730 #define symbol_put(x) do { } while (0)
731 #define symbol_put_addr(p) do { } while (0)
732
733 #endif /* CONFIG_MODULE_UNLOAD */
734
735 /* This is a #define so the string doesn't get put in every .o file */
736 #define module_name(mod) \
737 ({ \
738 struct module *__mod = (mod); \
739 __mod ? __mod->name : "kernel"; \
740 })
741
742 /* Dereference module function descriptor */
743 void *dereference_module_function_descriptor(struct module *mod, void *ptr);
744
745 int register_module_notifier(struct notifier_block *nb);
746 int unregister_module_notifier(struct notifier_block *nb);
747
748 extern void print_modules(void);
749
module_requested_async_probing(struct module * module)750 static inline bool module_requested_async_probing(struct module *module)
751 {
752 return module && module->async_probe_requested;
753 }
754
is_livepatch_module(struct module * mod)755 static inline bool is_livepatch_module(struct module *mod)
756 {
757 #ifdef CONFIG_LIVEPATCH
758 return mod->klp;
759 #else
760 return false;
761 #endif
762 }
763
764 void set_module_sig_enforced(void);
765
766 void module_for_each_mod(int(*func)(struct module *mod, void *data), void *data);
767
768 #else /* !CONFIG_MODULES... */
769
__module_address(unsigned long addr)770 static inline struct module *__module_address(unsigned long addr)
771 {
772 return NULL;
773 }
774
__module_text_address(unsigned long addr)775 static inline struct module *__module_text_address(unsigned long addr)
776 {
777 return NULL;
778 }
779
is_module_address(unsigned long addr)780 static inline bool is_module_address(unsigned long addr)
781 {
782 return false;
783 }
784
is_module_percpu_address(unsigned long addr)785 static inline bool is_module_percpu_address(unsigned long addr)
786 {
787 return false;
788 }
789
__is_module_percpu_address(unsigned long addr,unsigned long * can_addr)790 static inline bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr)
791 {
792 return false;
793 }
794
is_module_text_address(unsigned long addr)795 static inline bool is_module_text_address(unsigned long addr)
796 {
797 return false;
798 }
799
within_module_core(unsigned long addr,const struct module * mod)800 static inline bool within_module_core(unsigned long addr,
801 const struct module *mod)
802 {
803 return false;
804 }
805
within_module_init(unsigned long addr,const struct module * mod)806 static inline bool within_module_init(unsigned long addr,
807 const struct module *mod)
808 {
809 return false;
810 }
811
within_module(unsigned long addr,const struct module * mod)812 static inline bool within_module(unsigned long addr, const struct module *mod)
813 {
814 return false;
815 }
816
817 /* Get/put a kernel symbol (calls should be symmetric) */
818 #define symbol_get(x) ({ extern typeof(x) x __attribute__((weak,visibility("hidden"))); &(x); })
819 #define symbol_put(x) do { } while (0)
820 #define symbol_put_addr(x) do { } while (0)
821
__module_get(struct module * module)822 static inline void __module_get(struct module *module)
823 {
824 }
825
try_module_get(struct module * module)826 static inline bool try_module_get(struct module *module)
827 {
828 return true;
829 }
830
module_put(struct module * module)831 static inline void module_put(struct module *module)
832 {
833 }
834
835 #define module_name(mod) "kernel"
836
register_module_notifier(struct notifier_block * nb)837 static inline int register_module_notifier(struct notifier_block *nb)
838 {
839 /* no events will happen anyway, so this can always succeed */
840 return 0;
841 }
842
unregister_module_notifier(struct notifier_block * nb)843 static inline int unregister_module_notifier(struct notifier_block *nb)
844 {
845 return 0;
846 }
847
848 #define module_put_and_kthread_exit(code) kthread_exit(code)
849
print_modules(void)850 static inline void print_modules(void)
851 {
852 }
853
module_requested_async_probing(struct module * module)854 static inline bool module_requested_async_probing(struct module *module)
855 {
856 return false;
857 }
858
859
set_module_sig_enforced(void)860 static inline void set_module_sig_enforced(void)
861 {
862 }
863
864 /* Dereference module function descriptor */
865 static inline
dereference_module_function_descriptor(struct module * mod,void * ptr)866 void *dereference_module_function_descriptor(struct module *mod, void *ptr)
867 {
868 return ptr;
869 }
870
module_is_coming(struct module * mod)871 static inline bool module_is_coming(struct module *mod)
872 {
873 return false;
874 }
875
module_for_each_mod(int (* func)(struct module * mod,void * data),void * data)876 static inline void module_for_each_mod(int(*func)(struct module *mod, void *data), void *data)
877 {
878 }
879 #endif /* CONFIG_MODULES */
880
881 #ifdef CONFIG_SYSFS
882 extern struct kset *module_kset;
883 extern const struct kobj_type module_ktype;
884 #endif /* CONFIG_SYSFS */
885
886 #define symbol_request(x) try_then_request_module(symbol_get(x), "symbol:" #x)
887
888 /* BELOW HERE ALL THESE ARE OBSOLETE AND WILL VANISH */
889
890 #define __MODULE_STRING(x) __stringify(x)
891
892 #ifdef CONFIG_GENERIC_BUG
893 void module_bug_finalize(const Elf_Ehdr *, const Elf_Shdr *,
894 struct module *);
895 void module_bug_cleanup(struct module *);
896
897 #else /* !CONFIG_GENERIC_BUG */
898
module_bug_finalize(const Elf_Ehdr * hdr,const Elf_Shdr * sechdrs,struct module * mod)899 static inline void module_bug_finalize(const Elf_Ehdr *hdr,
900 const Elf_Shdr *sechdrs,
901 struct module *mod)
902 {
903 }
module_bug_cleanup(struct module * mod)904 static inline void module_bug_cleanup(struct module *mod) {}
905 #endif /* CONFIG_GENERIC_BUG */
906
907 #ifdef CONFIG_MITIGATION_RETPOLINE
908 extern bool retpoline_module_ok(bool has_retpoline);
909 #else
retpoline_module_ok(bool has_retpoline)910 static inline bool retpoline_module_ok(bool has_retpoline)
911 {
912 return true;
913 }
914 #endif
915
916 #ifdef CONFIG_MODULE_SIG
917 bool is_module_sig_enforced(void);
918
module_sig_ok(struct module * module)919 static inline bool module_sig_ok(struct module *module)
920 {
921 return module->sig_ok;
922 }
923 #else /* !CONFIG_MODULE_SIG */
is_module_sig_enforced(void)924 static inline bool is_module_sig_enforced(void)
925 {
926 return false;
927 }
928
module_sig_ok(struct module * module)929 static inline bool module_sig_ok(struct module *module)
930 {
931 return true;
932 }
933 #endif /* CONFIG_MODULE_SIG */
934
935 #if defined(CONFIG_MODULES) && defined(CONFIG_KALLSYMS)
936 int module_kallsyms_on_each_symbol(const char *modname,
937 int (*fn)(void *, const char *, unsigned long),
938 void *data);
939
940 /* For kallsyms to ask for address resolution. namebuf should be at
941 * least KSYM_NAME_LEN long: a pointer to namebuf is returned if
942 * found, otherwise NULL.
943 */
944 int module_address_lookup(unsigned long addr,
945 unsigned long *symbolsize,
946 unsigned long *offset,
947 char **modname, const unsigned char **modbuildid,
948 char *namebuf);
949 int lookup_module_symbol_name(unsigned long addr, char *symname);
950 int lookup_module_symbol_attrs(unsigned long addr,
951 unsigned long *size,
952 unsigned long *offset,
953 char *modname,
954 char *name);
955
956 /* Returns 0 and fills in value, defined and namebuf, or -ERANGE if
957 * symnum out of range.
958 */
959 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
960 char *name, char *module_name, int *exported);
961
962 /* Look for this name: can be of form module:name. */
963 unsigned long module_kallsyms_lookup_name(const char *name);
964
965 unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name);
966
967 #else /* CONFIG_MODULES && CONFIG_KALLSYMS */
968
module_kallsyms_on_each_symbol(const char * modname,int (* fn)(void *,const char *,unsigned long),void * data)969 static inline int module_kallsyms_on_each_symbol(const char *modname,
970 int (*fn)(void *, const char *, unsigned long),
971 void *data)
972 {
973 return -EOPNOTSUPP;
974 }
975
976 /* 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)977 static inline int module_address_lookup(unsigned long addr,
978 unsigned long *symbolsize,
979 unsigned long *offset,
980 char **modname,
981 const unsigned char **modbuildid,
982 char *namebuf)
983 {
984 return 0;
985 }
986
lookup_module_symbol_name(unsigned long addr,char * symname)987 static inline int lookup_module_symbol_name(unsigned long addr, char *symname)
988 {
989 return -ERANGE;
990 }
991
module_get_kallsym(unsigned int symnum,unsigned long * value,char * type,char * name,char * module_name,int * exported)992 static inline int module_get_kallsym(unsigned int symnum, unsigned long *value,
993 char *type, char *name,
994 char *module_name, int *exported)
995 {
996 return -ERANGE;
997 }
998
module_kallsyms_lookup_name(const char * name)999 static inline unsigned long module_kallsyms_lookup_name(const char *name)
1000 {
1001 return 0;
1002 }
1003
find_kallsyms_symbol_value(struct module * mod,const char * name)1004 static inline unsigned long find_kallsyms_symbol_value(struct module *mod,
1005 const char *name)
1006 {
1007 return 0;
1008 }
1009
1010 #endif /* CONFIG_MODULES && CONFIG_KALLSYMS */
1011
1012 /* Define __free(module_put) macro for struct module *. */
1013 DEFINE_FREE(module_put, struct module *, if (_T) module_put(_T))
1014
1015 #endif /* _LINUX_MODULE_H */
1016