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// SPDX-License-Identifier: GPL-2.0-or-later/* * Copyright (C) 2002 Richard Henderson * Copyright (C) 2001 Rusty Russell, 2002, 2010 Rusty Russell IBM. */ #define INCLUDE_VERMAGIC #include <linux/export.h>#include <linux/extable.h>#include <linux/moduleloader.h>#include <linux/module_signature.h>#include <linux/trace_events.h>#include <linux/init.h>#include <linux/kallsyms.h>#include <linux/file.h>#include <linux/fs.h>#include <linux/sysfs.h>#include <linux/kernel.h>#include <linux/kernel_read_file.h>#include <linux/slab.h>#include <linux/vmalloc.h>#include <linux/elf.h>#include <linux/proc_fs.h>#include <linux/security.h>#include <linux/seq_file.h>#include <linux/syscalls.h>#include <linux/fcntl.h>#include <linux/rcupdate.h>#include <linux/capability.h>#include <linux/cpu.h>#include <linux/moduleparam.h>#include <linux/errno.h>#include <linux/err.h>#include <linux/vermagic.h>#include <linux/notifier.h>#include <linux/sched.h>#include <linux/device.h>#include <linux/string.h>#include <linux/mutex.h>#include <linux/rculist.h>#include <linux/uaccess.h>#include <asm/cacheflush.h>#include <linux/set_memory.h>#include <asm/mmu_context.h>#include <linux/license.h>#include <asm/sections.h>#include <linux/tracepoint.h>#include <linux/ftrace.h>#include <linux/livepatch.h>#include <linux/async.h>#include <linux/percpu.h>#include <linux/kmemleak.h>#include <linux/jump_label.h>#include <linux/pfn.h>#include <linux/bsearch.h>#include <linux/dynamic_debug.h>#include <linux/audit.h>#include <uapi/linux/module.h>#include "module-internal.h" #define CREATE_TRACE_POINTS#include <trace/events/module.h> #ifndef ARCH_SHF_SMALL#define ARCH_SHF_SMALL 0#endif /* * Modules' sections will be aligned on page boundaries * to ensure complete separation of code and data, but * only when CONFIG_ARCH_HAS_STRICT_MODULE_RWX=y */#ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX# define debug_align(X) ALIGN(X, PAGE_SIZE)#else# define debug_align(X) (X)#endif /* If this is set, the section belongs in the init part of the module */#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1)) /* * Mutex protects: * 1) List of modules (also safely readable with preempt_disable), * 2) module_use links, * 3) module_addr_min/module_addr_max. * (delete and add uses RCU list operations). */static DEFINE_MUTEX(module_mutex);static LIST_HEAD(modules); /* Work queue for freeing init sections in success case */static void do_free_init(struct work_struct *w);static DECLARE_WORK(init_free_wq, do_free_init);static LLIST_HEAD(init_free_list); #ifdef CONFIG_MODULES_TREE_LOOKUP /* * Use a latched RB-tree for __module_address(); this allows us to use * RCU-sched lookups of the address from any context. * * This is conditional on PERF_EVENTS || TRACING because those can really hit * __module_address() hard by doing a lot of stack unwinding; potentially from * NMI context. */ static __always_inline unsigned long __mod_tree_val(struct latch_tree_node *n){	struct module_layout *layout = container_of(n, struct module_layout, mtn.node); 	return (unsigned long)layout->base;} static __always_inline unsigned long __mod_tree_size(struct latch_tree_node *n){	struct module_layout *layout = container_of(n, struct module_layout, mtn.node); 	return (unsigned long)layout->size;} static __always_inline boolmod_tree_less(struct latch_tree_node *a, struct latch_tree_node *b){	return __mod_tree_val(a) < __mod_tree_val(b);} static __always_inline intmod_tree_comp(void *key, struct latch_tree_node *n){	unsigned long val = (unsigned long)key;	unsigned long start, end; 	start = __mod_tree_val(n);	if (val < start)		return -1; 	end = start + __mod_tree_size(n);	if (val >= end)		return 1; 	return 0;} static const struct latch_tree_ops mod_tree_ops = {	.less = mod_tree_less,	.comp = mod_tree_comp,}; static struct mod_tree_root {	struct latch_tree_root root;	unsigned long addr_min;	unsigned long addr_max;} mod_tree __cacheline_aligned = {	.addr_min = -1UL,}; #define module_addr_min mod_tree.addr_min#define module_addr_max mod_tree.addr_max static noinline void __mod_tree_insert(struct mod_tree_node *node){	latch_tree_insert(&node->node, &mod_tree.root, &mod_tree_ops);} static void __mod_tree_remove(struct mod_tree_node *node){	latch_tree_erase(&node->node, &mod_tree.root, &mod_tree_ops);} /* * These modifications: insert, remove_init and remove; are serialized by the * module_mutex. */static void mod_tree_insert(struct module *mod){	mod->core_layout.mtn.mod = mod;	mod->init_layout.mtn.mod = mod; 	__mod_tree_insert(&mod->core_layout.mtn);	if (mod->init_layout.size)		__mod_tree_insert(&mod->init_layout.mtn);} static void mod_tree_remove_init(struct module *mod){	if (mod->init_layout.size)		__mod_tree_remove(&mod->init_layout.mtn);} static void mod_tree_remove(struct module *mod){	__mod_tree_remove(&mod->core_layout.mtn);	mod_tree_remove_init(mod);} static struct module *mod_find(unsigned long addr){	struct latch_tree_node *ltn; 	ltn = latch_tree_find((void *)addr, &mod_tree.root, &mod_tree_ops);	if (!ltn)		return NULL; 	return container_of(ltn, struct mod_tree_node, node)->mod;} #else /* MODULES_TREE_LOOKUP */ static unsigned long module_addr_min = -1UL, module_addr_max = 0; static void mod_tree_insert(struct module *mod) { }static void mod_tree_remove_init(struct module *mod) { }static void mod_tree_remove(struct module *mod) { } static struct module *mod_find(unsigned long addr){	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 /* MODULES_TREE_LOOKUP */ /* * Bounds of module text, for speeding up __module_address. * Protected by module_mutex. */static void __mod_update_bounds(void *base, unsigned int size){	unsigned long min = (unsigned long)base;	unsigned long max = min + size; 	if (min < module_addr_min)		module_addr_min = min;	if (max > module_addr_max)		module_addr_max = max;} static void mod_update_bounds(struct module *mod){	__mod_update_bounds(mod->core_layout.base, mod->core_layout.size);	if (mod->init_layout.size)		__mod_update_bounds(mod->init_layout.base, mod->init_layout.size);} #ifdef CONFIG_KGDB_KDBstruct list_head *kdb_modules = &modules; /* kdb needs the list of modules */#endif /* CONFIG_KGDB_KDB */ static 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 bool sig_enforce = IS_ENABLED(CONFIG_MODULE_SIG_FORCE);module_param(sig_enforce, bool_enable_only, 0644); /* * Export sig_enforce kernel cmdline parameter to allow other subsystems rely * on that instead of directly to CONFIG_MODULE_SIG_FORCE config. */bool is_module_sig_enforced(void){	return sig_enforce;}EXPORT_SYMBOL(is_module_sig_enforced); void set_module_sig_enforced(void){	sig_enforce = true;} /* Block module loading/unloading? */int modules_disabled = 0;core_param(nomodule, modules_disabled, bint, 0); /* Waiting for a module to finish initializing? */static DECLARE_WAIT_QUEUE_HEAD(module_wq); static BLOCKING_NOTIFIER_HEAD(module_notify_list); int register_module_notifier(struct notifier_block *nb){	return blocking_notifier_chain_register(&module_notify_list, nb);}EXPORT_SYMBOL(register_module_notifier); int unregister_module_notifier(struct notifier_block *nb){	return blocking_notifier_chain_unregister(&module_notify_list, nb);}EXPORT_SYMBOL(unregister_module_notifier); /* * We require a truly strong try_module_get(): 0 means success. * Otherwise an error is returned due to ongoing or failed * initialization etc. */static inline int strong_try_module_get(struct module *mod){	BUG_ON(mod && mod->state == MODULE_STATE_UNFORMED);	if (mod && mod->state == MODULE_STATE_COMING)		return -EBUSY;	if (try_module_get(mod))		return 0;	else		return -ENOENT;} static inline void add_taint_module(struct module *mod, unsigned flag,				    enum lockdep_ok lockdep_ok){	add_taint(flag, lockdep_ok);	set_bit(flag, &mod->taints);} /* * A thread that wants to hold a reference to a module only while it * is running can call this to safely exit.  nfsd and lockd use this. */void __noreturn __module_put_and_exit(struct module *mod, long code){	module_put(mod);	do_exit(code);}EXPORT_SYMBOL(__module_put_and_exit); /* Find a module section: 0 means not found. */static unsigned int find_sec(const struct load_info *info, const char *name){	unsigned int i; 	for (i = 1; i < info->hdr->e_shnum; i++) {		Elf_Shdr *shdr = &info->sechdrs[i];		/* Alloc bit cleared means "ignore it." */		if ((shdr->sh_flags & SHF_ALLOC)		    && strcmp(info->secstrings + shdr->sh_name, name) == 0)			return i;	}	return 0;} /* Find a module section, or NULL. */static void *section_addr(const struct load_info *info, const char *name){	/* Section 0 has sh_addr 0. */	return (void *)info->sechdrs[find_sec(info, name)].sh_addr;} /* Find a module section, or NULL.  Fill in number of "objects" in section. */static void *section_objs(const struct load_info *info,			  const char *name,			  size_t object_size,			  unsigned int *num){	unsigned int sec = find_sec(info, name); 	/* Section 0 has sh_addr 0 and sh_size 0. */	*num = info->sechdrs[sec].sh_size / object_size;	return (void *)info->sechdrs[sec].sh_addr;} /* Find a module section: 0 means not found. Ignores SHF_ALLOC flag. */static unsigned int find_any_sec(const struct load_info *info, const char *name){	unsigned int i; 	for (i = 1; i < info->hdr->e_shnum; i++) {		Elf_Shdr *shdr = &info->sechdrs[i];		if (strcmp(info->secstrings + shdr->sh_name, name) == 0)			return i;	}	return 0;} /* * Find a module section, or NULL. Fill in number of "objects" in section. * Ignores SHF_ALLOC flag. */static __maybe_unused void *any_section_objs(const struct load_info *info,					     const char *name,					     size_t object_size,					     unsigned int *num){	unsigned int sec = find_any_sec(info, name); 	/* Section 0 has sh_addr 0 and sh_size 0. */	*num = info->sechdrs[sec].sh_size / object_size;	return (void *)info->sechdrs[sec].sh_addr;} /* 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[]; #ifndef CONFIG_MODVERSIONS#define symversion(base, idx) NULL#else#define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)#endif struct symsearch {	const struct kernel_symbol *start, *stop;	const s32 *crcs;	enum mod_license {		NOT_GPL_ONLY,		GPL_ONLY,	} license;}; 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;}; static bool check_exported_symbol(const struct symsearch *syms,				  struct module *owner,				  unsigned int symnum, void *data){	struct find_symbol_arg *fsa = data; 	if (!fsa->gplok && syms->license == GPL_ONLY)		return false;	fsa->owner = owner;	fsa->crc = symversion(syms->crcs, symnum);	fsa->sym = &syms->start[symnum];	fsa->license = syms->license;	return true;} static 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} static const char *kernel_symbol_name(const struct kernel_symbol *sym){#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS	return offset_to_ptr(&sym->name_offset);#else	return sym->name;#endif} static const char *kernel_symbol_namespace(const struct kernel_symbol *sym){#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS	if (!sym->namespace_offset)		return NULL;	return offset_to_ptr(&sym->namespace_offset);#else	return sym->namespace;#endif} static int cmp_name(const void *name, const void *sym){	return strcmp(name, kernel_symbol_name(sym));} static bool find_exported_symbol_in_section(const struct symsearch *syms,					    struct module *owner,					    void *data){	struct find_symbol_arg *fsa = data;	struct kernel_symbol *sym; 	sym = bsearch(fsa->name, syms->start, syms->stop - syms->start,			sizeof(struct kernel_symbol), cmp_name); 

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