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Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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#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
/* * Use highest 4 bits of sh_entsize to store the mod_mem_type of this * section. This leaves 28 bits for offset on 32-bit systems, which is * about 256 MiB (WARN_ON_ONCE if we exceed that). */
#define SH_ENTSIZE_TYPE_BITS 4#define SH_ENTSIZE_TYPE_SHIFT (BITS_PER_LONG - SH_ENTSIZE_TYPE_BITS)#define SH_ENTSIZE_TYPE_MASK ((1UL << SH_ENTSIZE_TYPE_BITS) - 1)#define SH_ENTSIZE_OFFSET_MASK ((1UL << (BITS_PER_LONG - SH_ENTSIZE_TYPE_BITS)) - 1)
/* Maximum number of characters written by module_flags() */#define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4)
struct kernel_symbol {#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS int value_offset; int name_offset; int namespace_offset;#else unsigned long value; const char *name; const char *namespace;#endif};
extern struct mutex module_mutex;extern struct list_head modules;
extern const struct module_attribute *const modinfo_attrs[];extern const 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 u32 __start___kcrctab[];extern const u8 __start___kflagstab[];
#define KMOD_PATH_LEN 256extern char modprobe_path[];
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; bool sig_ok;#ifdef CONFIG_KALLSYMS unsigned long mod_kallsyms_init_off;#endif#ifdef CONFIG_MODULE_DECOMPRESS#ifdef CONFIG_MODULE_STATS unsigned long compressed_len;#endif struct page **pages; unsigned int max_pages; unsigned int used_pages;#endif struct { unsigned int sym; unsigned int str; unsigned int mod; unsigned int vers; unsigned int info; unsigned int pcpu; unsigned int vers_ext_crc; unsigned int vers_ext_name; } 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 u32 *crc; const struct kernel_symbol *sym; enum mod_license license;};
/* modules using other modules */struct module_use { struct list_head source_list; struct list_head target_list; struct module *source, *target;};
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_and_type(struct module *mod, enum mod_mem_type type, 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);
char *module_next_tag_pair(char *string, unsigned long *secsize);
#define for_each_modinfo_entry(entry, info, name) \ for (entry = get_modinfo(info, name); entry; entry = get_next_modinfo(info, name, entry))
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}
/** * enum fail_dup_mod_reason - state at which a duplicate module was detected * * @FAIL_DUP_MOD_BECOMING: the module is read properly, passes all checks but * we've determined that another module with the same name is already loaded * or being processed on our &modules list. This happens on early_mod_check() * right before layout_and_allocate(). The kernel would have already * vmalloc()'d space for the entire module through finit_module(). If * decompression was used two vmap() spaces were used. These failures can * happen when userspace has not seen the module present on the kernel and * tries to load the module multiple times at same time. * @FAIL_DUP_MOD_LOAD: the module has been read properly, passes all validation * checks and the kernel determines that the module was unique and because * of this allocated yet another private kernel copy of the module space in * layout_and_allocate() but after this determined in add_unformed_module() * that another module with the same name is already loaded or being processed. * These failures should be mitigated as much as possible and are indicative * of really fast races in loading modules. Without module decompression * they waste twice as much vmap space. With module decompression three * times the module's size vmap space is wasted. */enum fail_dup_mod_reason { FAIL_DUP_MOD_BECOMING = 0, FAIL_DUP_MOD_LOAD,};
#ifdef CONFIG_MODULE_DEBUGFSextern struct dentry *mod_debugfs_root;#endif
#ifdef CONFIG_MODULE_STATS
#define mod_stat_add_long(count, var) atomic_long_add(count, var)#define mod_stat_inc(name) atomic_inc(name)
extern atomic_long_t total_mod_size;extern atomic_long_t total_text_size;extern atomic_long_t invalid_kread_bytes;extern atomic_long_t invalid_decompress_bytes;
extern atomic_t modcount;extern atomic_t failed_kreads;extern atomic_t failed_decompress;struct mod_fail_load { struct list_head list; char name[MODULE_NAME_LEN]; atomic_long_t count; unsigned long dup_fail_mask;};
int try_add_failed_module(const char *name, enum fail_dup_mod_reason reason);void mod_stat_bump_invalid(struct load_info *info, int flags);void mod_stat_bump_becoming(struct load_info *info, int flags);
#else
#define mod_stat_add_long(name, var)#define mod_stat_inc(name)
static inline int try_add_failed_module(const char *name, enum fail_dup_mod_reason reason){ return 0;}
static inline void mod_stat_bump_invalid(struct load_info *info, int flags){}
static inline void mod_stat_bump_becoming(struct load_info *info, int flags){}
#endif /* CONFIG_MODULE_STATS */
#ifdef CONFIG_MODULE_DEBUG_AUTOLOAD_DUPSbool kmod_dup_request_exists_wait(char *module_name, bool wait, int *dup_ret);void kmod_dup_request_announce(char *module_name, int ret);#elsestatic inline bool kmod_dup_request_exists_wait(char *module_name, bool wait, int *dup_ret){ return false;}
static inline void kmod_dup_request_announce(char *module_name, int ret){}#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;#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC unsigned long data_addr_min; unsigned long data_addr_max;#endif};
extern struct mod_tree_root mod_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 */
int module_enable_rodata_ro(const struct module *mod);int module_enable_rodata_ro_after_init(const struct module *mod);int module_enable_data_nx(const struct module *mod);int module_enable_text_rox(const struct module *mod);int module_enforce_rwx_sections(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs, const char *secstrings, const struct module *mod);void module_mark_ro_after_init(const Elf_Ehdr *hdr, Elf_Shdr *sechdrs, const char *secstrings);
#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);
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 u32 *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);struct modversion_info_ext { size_t remaining; const u32 *crc; const char *name;};void modversion_ext_start(const struct load_info *info, struct modversion_info_ext *ver);void modversion_ext_advance(struct modversion_info_ext *ver);#define for_each_modversion_info_ext(ver, info) \ for (modversion_ext_start(info, &ver); ver.remaining > 0; modversion_ext_advance(&ver))#else /* !CONFIG_MODVERSIONS */static inline int check_version(const struct load_info *info, const char *symname, struct module *mod, const u32 *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 */