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/* SPDX-License-Identifier: GPL-2.0-or-later *//* Module internals * * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. * Written by David Howells (dhowells@redhat.com) */ #include <linux/elf.h>#include <linux/compiler.h>#include <linux/module.h>#include <linux/mutex.h>#include <linux/rculist.h>#include <linux/rcupdate.h>#include <linux/mm.h> #ifndef ARCH_SHF_SMALL#define ARCH_SHF_SMALL 0#endif /* If this is set, the section belongs in the init part of the module */#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG - 1))/* Maximum number of characters written by module_flags() */#define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4) #ifndef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC#define	data_layout core_layout#endif /* * Modules' sections will be aligned on page boundaries * to ensure complete separation of code and data, but * only when CONFIG_STRICT_MODULE_RWX=y */static inline unsigned int strict_align(unsigned int size){	if (IS_ENABLED(CONFIG_STRICT_MODULE_RWX))		return PAGE_ALIGN(size);	else		return size;} extern struct mutex module_mutex;extern struct list_head modules; extern struct module_attribute *modinfo_attrs[];extern size_t modinfo_attrs_count; /* Provided by the linker */extern const struct kernel_symbol __start___ksymtab[];extern const struct kernel_symbol __stop___ksymtab[];extern const struct kernel_symbol __start___ksymtab_gpl[];extern const struct kernel_symbol __stop___ksymtab_gpl[];extern const s32 __start___kcrctab[];extern const s32 __start___kcrctab_gpl[]; #include <linux/dynamic_debug.h>struct load_info {	const char *name;	/* pointer to module in temporary copy, freed at end of load_module() */	struct module *mod;	Elf_Ehdr *hdr;	unsigned long len;	Elf_Shdr *sechdrs;	char *secstrings, *strtab;	unsigned long symoffs, stroffs, init_typeoffs, core_typeoffs;	struct _ddebug_info dyndbg;	bool sig_ok;#ifdef CONFIG_KALLSYMS	unsigned long mod_kallsyms_init_off;#endif#ifdef CONFIG_MODULE_DECOMPRESS	struct page **pages;	unsigned int max_pages;	unsigned int used_pages;#endif	struct {		unsigned int sym, str, mod, vers, info, pcpu;	} index;}; enum mod_license {	NOT_GPL_ONLY,	GPL_ONLY,}; struct find_symbol_arg {	/* Input */	const char *name;	bool gplok;	bool warn; 	/* Output */	struct module *owner;	const s32 *crc;	const struct kernel_symbol *sym;	enum mod_license license;}; int mod_verify_sig(const void *mod, struct load_info *info);int try_to_force_load(struct module *mod, const char *reason);bool find_symbol(struct find_symbol_arg *fsa);struct module *find_module_all(const char *name, size_t len, bool even_unformed);int cmp_name(const void *name, const void *sym);long module_get_offset(struct module *mod, unsigned int *size, Elf_Shdr *sechdr,		       unsigned int section);char *module_flags(struct module *mod, char *buf, bool show_state);size_t module_flags_taint(unsigned long taints, char *buf); static inline void module_assert_mutex_or_preempt(void){#ifdef CONFIG_LOCKDEP	if (unlikely(!debug_locks))		return; 	WARN_ON_ONCE(!rcu_read_lock_sched_held() &&		     !lockdep_is_held(&module_mutex));#endif} static inline unsigned long kernel_symbol_value(const struct kernel_symbol *sym){#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS	return (unsigned long)offset_to_ptr(&sym->value_offset);#else	return sym->value;#endif} #ifdef CONFIG_LIVEPATCHint copy_module_elf(struct module *mod, struct load_info *info);void free_module_elf(struct module *mod);#else /* !CONFIG_LIVEPATCH */static inline int copy_module_elf(struct module *mod, struct load_info *info){	return 0;} static inline void free_module_elf(struct module *mod) { }#endif /* CONFIG_LIVEPATCH */ static inline bool set_livepatch_module(struct module *mod){#ifdef CONFIG_LIVEPATCH	mod->klp = true;	return true;#else	return false;#endif} #ifdef CONFIG_MODULE_UNLOAD_TAINT_TRACKINGstruct mod_unload_taint {	struct list_head list;	char name[MODULE_NAME_LEN];	unsigned long taints;	u64 count;}; int try_add_tainted_module(struct module *mod);void print_unloaded_tainted_modules(void);#else /* !CONFIG_MODULE_UNLOAD_TAINT_TRACKING */static inline int try_add_tainted_module(struct module *mod){	return 0;} static inline void print_unloaded_tainted_modules(void){}#endif /* CONFIG_MODULE_UNLOAD_TAINT_TRACKING */ #ifdef CONFIG_MODULE_DECOMPRESSint module_decompress(struct load_info *info, const void *buf, size_t size);void module_decompress_cleanup(struct load_info *info);#elsestatic inline int module_decompress(struct load_info *info,				    const void *buf, size_t size){	return -EOPNOTSUPP;} static inline void module_decompress_cleanup(struct load_info *info){}#endif struct mod_tree_root {#ifdef CONFIG_MODULES_TREE_LOOKUP	struct latch_tree_root root;#endif	unsigned long addr_min;	unsigned long addr_max;}; extern struct mod_tree_root mod_tree;extern struct mod_tree_root mod_data_tree; #ifdef CONFIG_MODULES_TREE_LOOKUPvoid mod_tree_insert(struct module *mod);void mod_tree_remove_init(struct module *mod);void mod_tree_remove(struct module *mod);struct module *mod_find(unsigned long addr, struct mod_tree_root *tree);#else /* !CONFIG_MODULES_TREE_LOOKUP */ static inline void mod_tree_insert(struct module *mod) { }static inline void mod_tree_remove_init(struct module *mod) { }static inline void mod_tree_remove(struct module *mod) { }static inline struct module *mod_find(unsigned long addr, struct mod_tree_root *tree){	struct module *mod; 	list_for_each_entry_rcu(mod, &modules, list,				lockdep_is_held(&module_mutex)) {		if (within_module(addr, mod))			return mod;	} 	return NULL;}#endif /* CONFIG_MODULES_TREE_LOOKUP */ void module_enable_ro(const struct module *mod, bool after_init);void module_enable_nx(const struct module *mod);void module_enable_x(const struct module *mod);int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,				char *secstrings, struct module *mod);bool module_check_misalignment(const struct module *mod); #ifdef CONFIG_MODULE_SIGint module_sig_check(struct load_info *info, int flags);#else /* !CONFIG_MODULE_SIG */static inline int module_sig_check(struct load_info *info, int flags){	return 0;}#endif /* !CONFIG_MODULE_SIG */ #ifdef CONFIG_DEBUG_KMEMLEAKvoid kmemleak_load_module(const struct module *mod, const struct load_info *info);#else /* !CONFIG_DEBUG_KMEMLEAK */static inline void kmemleak_load_module(const struct module *mod,					const struct load_info *info) { }#endif /* CONFIG_DEBUG_KMEMLEAK */ #ifdef CONFIG_KALLSYMSvoid init_build_id(struct module *mod, const struct load_info *info);void layout_symtab(struct module *mod, struct load_info *info);void add_kallsyms(struct module *mod, const struct load_info *info);unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name); static inline bool sect_empty(const Elf_Shdr *sect){	return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;}#else /* !CONFIG_KALLSYMS */static inline void init_build_id(struct module *mod, const struct load_info *info) { }static inline void layout_symtab(struct module *mod, struct load_info *info) { }static inline void add_kallsyms(struct module *mod, const struct load_info *info) { }#endif /* CONFIG_KALLSYMS */ #ifdef CONFIG_SYSFSint mod_sysfs_setup(struct module *mod, const struct load_info *info,		    struct kernel_param *kparam, unsigned int num_params);void mod_sysfs_teardown(struct module *mod);void init_param_lock(struct module *mod);#else /* !CONFIG_SYSFS */static inline int mod_sysfs_setup(struct module *mod,			   	  const struct load_info *info,			   	  struct kernel_param *kparam,			   	  unsigned int num_params){	return 0;} static inline void mod_sysfs_teardown(struct module *mod) { }static inline void init_param_lock(struct module *mod) { }#endif /* CONFIG_SYSFS */ #ifdef CONFIG_MODVERSIONSint check_version(const struct load_info *info,		  const char *symname, struct module *mod, const s32 *crc);void module_layout(struct module *mod, struct modversion_info *ver, struct kernel_param *kp,		   struct kernel_symbol *ks, struct tracepoint * const *tp);int check_modstruct_version(const struct load_info *info, struct module *mod);int same_magic(const char *amagic, const char *bmagic, bool has_crcs);#else /* !CONFIG_MODVERSIONS */static inline int check_version(const struct load_info *info,				const char *symname,				struct module *mod,				const s32 *crc){	return 1;} static inline int check_modstruct_version(const struct load_info *info,					  struct module *mod){	return 1;} static inline int same_magic(const char *amagic, const char *bmagic, bool has_crcs){	return strcmp(amagic, bmagic) == 0;}#endif /* CONFIG_MODVERSIONS */