internal.h (8724B)
1/* SPDX-License-Identifier: GPL-2.0-or-later */ 2/* Module internals 3 * 4 * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. 5 * Written by David Howells (dhowells@redhat.com) 6 */ 7 8#include <linux/elf.h> 9#include <linux/compiler.h> 10#include <linux/module.h> 11#include <linux/mutex.h> 12#include <linux/rculist.h> 13#include <linux/rcupdate.h> 14 15#ifndef ARCH_SHF_SMALL 16#define ARCH_SHF_SMALL 0 17#endif 18 19/* If this is set, the section belongs in the init part of the module */ 20#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG - 1)) 21/* Maximum number of characters written by module_flags() */ 22#define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4) 23 24#ifndef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC 25#define data_layout core_layout 26#endif 27 28/* 29 * Modules' sections will be aligned on page boundaries 30 * to ensure complete separation of code and data, but 31 * only when CONFIG_STRICT_MODULE_RWX=y 32 */ 33#ifdef CONFIG_STRICT_MODULE_RWX 34# define strict_align(X) PAGE_ALIGN(X) 35#else 36# define strict_align(X) (X) 37#endif 38 39extern struct mutex module_mutex; 40extern struct list_head modules; 41 42extern struct module_attribute *modinfo_attrs[]; 43extern size_t modinfo_attrs_count; 44 45/* Provided by the linker */ 46extern const struct kernel_symbol __start___ksymtab[]; 47extern const struct kernel_symbol __stop___ksymtab[]; 48extern const struct kernel_symbol __start___ksymtab_gpl[]; 49extern const struct kernel_symbol __stop___ksymtab_gpl[]; 50extern const s32 __start___kcrctab[]; 51extern const s32 __start___kcrctab_gpl[]; 52 53struct load_info { 54 const char *name; 55 /* pointer to module in temporary copy, freed at end of load_module() */ 56 struct module *mod; 57 Elf_Ehdr *hdr; 58 unsigned long len; 59 Elf_Shdr *sechdrs; 60 char *secstrings, *strtab; 61 unsigned long symoffs, stroffs, init_typeoffs, core_typeoffs; 62 struct _ddebug *debug; 63 unsigned int num_debug; 64 bool sig_ok; 65#ifdef CONFIG_KALLSYMS 66 unsigned long mod_kallsyms_init_off; 67#endif 68#ifdef CONFIG_MODULE_DECOMPRESS 69 struct page **pages; 70 unsigned int max_pages; 71 unsigned int used_pages; 72#endif 73 struct { 74 unsigned int sym, str, mod, vers, info, pcpu; 75 } index; 76}; 77 78enum mod_license { 79 NOT_GPL_ONLY, 80 GPL_ONLY, 81}; 82 83struct find_symbol_arg { 84 /* Input */ 85 const char *name; 86 bool gplok; 87 bool warn; 88 89 /* Output */ 90 struct module *owner; 91 const s32 *crc; 92 const struct kernel_symbol *sym; 93 enum mod_license license; 94}; 95 96int mod_verify_sig(const void *mod, struct load_info *info); 97int try_to_force_load(struct module *mod, const char *reason); 98bool find_symbol(struct find_symbol_arg *fsa); 99struct module *find_module_all(const char *name, size_t len, bool even_unformed); 100int cmp_name(const void *name, const void *sym); 101long module_get_offset(struct module *mod, unsigned int *size, Elf_Shdr *sechdr, 102 unsigned int section); 103char *module_flags(struct module *mod, char *buf); 104size_t module_flags_taint(unsigned long taints, char *buf); 105 106static inline void module_assert_mutex_or_preempt(void) 107{ 108#ifdef CONFIG_LOCKDEP 109 if (unlikely(!debug_locks)) 110 return; 111 112 WARN_ON_ONCE(!rcu_read_lock_sched_held() && 113 !lockdep_is_held(&module_mutex)); 114#endif 115} 116 117static inline unsigned long kernel_symbol_value(const struct kernel_symbol *sym) 118{ 119#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS 120 return (unsigned long)offset_to_ptr(&sym->value_offset); 121#else 122 return sym->value; 123#endif 124} 125 126#ifdef CONFIG_LIVEPATCH 127int copy_module_elf(struct module *mod, struct load_info *info); 128void free_module_elf(struct module *mod); 129#else /* !CONFIG_LIVEPATCH */ 130static inline int copy_module_elf(struct module *mod, struct load_info *info) 131{ 132 return 0; 133} 134 135static inline void free_module_elf(struct module *mod) { } 136#endif /* CONFIG_LIVEPATCH */ 137 138static inline bool set_livepatch_module(struct module *mod) 139{ 140#ifdef CONFIG_LIVEPATCH 141 mod->klp = true; 142 return true; 143#else 144 return false; 145#endif 146} 147 148#ifdef CONFIG_MODULE_UNLOAD_TAINT_TRACKING 149struct mod_unload_taint { 150 struct list_head list; 151 char name[MODULE_NAME_LEN]; 152 unsigned long taints; 153 u64 count; 154}; 155 156int try_add_tainted_module(struct module *mod); 157void print_unloaded_tainted_modules(void); 158#else /* !CONFIG_MODULE_UNLOAD_TAINT_TRACKING */ 159static inline int try_add_tainted_module(struct module *mod) 160{ 161 return 0; 162} 163 164static inline void print_unloaded_tainted_modules(void) 165{ 166} 167#endif /* CONFIG_MODULE_UNLOAD_TAINT_TRACKING */ 168 169#ifdef CONFIG_MODULE_DECOMPRESS 170int module_decompress(struct load_info *info, const void *buf, size_t size); 171void module_decompress_cleanup(struct load_info *info); 172#else 173static inline int module_decompress(struct load_info *info, 174 const void *buf, size_t size) 175{ 176 return -EOPNOTSUPP; 177} 178 179static inline void module_decompress_cleanup(struct load_info *info) 180{ 181} 182#endif 183 184struct mod_tree_root { 185#ifdef CONFIG_MODULES_TREE_LOOKUP 186 struct latch_tree_root root; 187#endif 188 unsigned long addr_min; 189 unsigned long addr_max; 190}; 191 192extern struct mod_tree_root mod_tree; 193extern struct mod_tree_root mod_data_tree; 194 195#ifdef CONFIG_MODULES_TREE_LOOKUP 196void mod_tree_insert(struct module *mod); 197void mod_tree_remove_init(struct module *mod); 198void mod_tree_remove(struct module *mod); 199struct module *mod_find(unsigned long addr, struct mod_tree_root *tree); 200#else /* !CONFIG_MODULES_TREE_LOOKUP */ 201 202static inline void mod_tree_insert(struct module *mod) { } 203static inline void mod_tree_remove_init(struct module *mod) { } 204static inline void mod_tree_remove(struct module *mod) { } 205static inline struct module *mod_find(unsigned long addr, struct mod_tree_root *tree) 206{ 207 struct module *mod; 208 209 list_for_each_entry_rcu(mod, &modules, list, 210 lockdep_is_held(&module_mutex)) { 211 if (within_module(addr, mod)) 212 return mod; 213 } 214 215 return NULL; 216} 217#endif /* CONFIG_MODULES_TREE_LOOKUP */ 218 219void module_enable_ro(const struct module *mod, bool after_init); 220void module_enable_nx(const struct module *mod); 221void module_enable_x(const struct module *mod); 222int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs, 223 char *secstrings, struct module *mod); 224bool module_check_misalignment(const struct module *mod); 225 226#ifdef CONFIG_MODULE_SIG 227int module_sig_check(struct load_info *info, int flags); 228#else /* !CONFIG_MODULE_SIG */ 229static inline int module_sig_check(struct load_info *info, int flags) 230{ 231 return 0; 232} 233#endif /* !CONFIG_MODULE_SIG */ 234 235#ifdef CONFIG_DEBUG_KMEMLEAK 236void kmemleak_load_module(const struct module *mod, const struct load_info *info); 237#else /* !CONFIG_DEBUG_KMEMLEAK */ 238static inline void kmemleak_load_module(const struct module *mod, 239 const struct load_info *info) { } 240#endif /* CONFIG_DEBUG_KMEMLEAK */ 241 242#ifdef CONFIG_KALLSYMS 243void init_build_id(struct module *mod, const struct load_info *info); 244void layout_symtab(struct module *mod, struct load_info *info); 245void add_kallsyms(struct module *mod, const struct load_info *info); 246unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name); 247 248static inline bool sect_empty(const Elf_Shdr *sect) 249{ 250 return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0; 251} 252#else /* !CONFIG_KALLSYMS */ 253static inline void init_build_id(struct module *mod, const struct load_info *info) { } 254static inline void layout_symtab(struct module *mod, struct load_info *info) { } 255static inline void add_kallsyms(struct module *mod, const struct load_info *info) { } 256#endif /* CONFIG_KALLSYMS */ 257 258#ifdef CONFIG_SYSFS 259int mod_sysfs_setup(struct module *mod, const struct load_info *info, 260 struct kernel_param *kparam, unsigned int num_params); 261void mod_sysfs_teardown(struct module *mod); 262void init_param_lock(struct module *mod); 263#else /* !CONFIG_SYSFS */ 264static inline int mod_sysfs_setup(struct module *mod, 265 const struct load_info *info, 266 struct kernel_param *kparam, 267 unsigned int num_params) 268{ 269 return 0; 270} 271 272static inline void mod_sysfs_teardown(struct module *mod) { } 273static inline void init_param_lock(struct module *mod) { } 274#endif /* CONFIG_SYSFS */ 275 276#ifdef CONFIG_MODVERSIONS 277int check_version(const struct load_info *info, 278 const char *symname, struct module *mod, const s32 *crc); 279void module_layout(struct module *mod, struct modversion_info *ver, struct kernel_param *kp, 280 struct kernel_symbol *ks, struct tracepoint * const *tp); 281int check_modstruct_version(const struct load_info *info, struct module *mod); 282int same_magic(const char *amagic, const char *bmagic, bool has_crcs); 283#else /* !CONFIG_MODVERSIONS */ 284static inline int check_version(const struct load_info *info, 285 const char *symname, 286 struct module *mod, 287 const s32 *crc) 288{ 289 return 1; 290} 291 292static inline int check_modstruct_version(const struct load_info *info, 293 struct module *mod) 294{ 295 return 1; 296} 297 298static inline int same_magic(const char *amagic, const char *bmagic, bool has_crcs) 299{ 300 return strcmp(amagic, bmagic) == 0; 301} 302#endif /* CONFIG_MODVERSIONS */