1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #include <stdbool.h> 3 #include <stdio.h> 4 #include <stdlib.h> 5 #include <stdarg.h> 6 #include <string.h> 7 #include <sys/types.h> 8 #include <sys/stat.h> 9 #include <sys/mman.h> 10 #include <fcntl.h> 11 #include <unistd.h> 12 #include <elf.h> 13 14 #include "list.h" 15 #include "elfconfig.h" 16 17 /* On BSD-alike OSes elf.h defines these according to host's word size */ 18 #undef ELF_ST_BIND 19 #undef ELF_ST_TYPE 20 #undef ELF_R_SYM 21 #undef ELF_R_TYPE 22 23 #if KERNEL_ELFCLASS == ELFCLASS32 24 25 #define Elf_Ehdr Elf32_Ehdr 26 #define Elf_Shdr Elf32_Shdr 27 #define Elf_Sym Elf32_Sym 28 #define Elf_Addr Elf32_Addr 29 #define Elf_Sword Elf64_Sword 30 #define Elf_Section Elf32_Half 31 #define ELF_ST_BIND ELF32_ST_BIND 32 #define ELF_ST_TYPE ELF32_ST_TYPE 33 34 #define Elf_Rel Elf32_Rel 35 #define Elf_Rela Elf32_Rela 36 #define ELF_R_SYM ELF32_R_SYM 37 #define ELF_R_TYPE ELF32_R_TYPE 38 #else 39 40 #define Elf_Ehdr Elf64_Ehdr 41 #define Elf_Shdr Elf64_Shdr 42 #define Elf_Sym Elf64_Sym 43 #define Elf_Addr Elf64_Addr 44 #define Elf_Sword Elf64_Sxword 45 #define Elf_Section Elf64_Half 46 #define ELF_ST_BIND ELF64_ST_BIND 47 #define ELF_ST_TYPE ELF64_ST_TYPE 48 49 #define Elf_Rel Elf64_Rel 50 #define Elf_Rela Elf64_Rela 51 #define ELF_R_SYM ELF64_R_SYM 52 #define ELF_R_TYPE ELF64_R_TYPE 53 #endif 54 55 /* The 64-bit MIPS ELF ABI uses an unusual reloc format. */ 56 typedef struct 57 { 58 Elf32_Word r_sym; /* Symbol index */ 59 unsigned char r_ssym; /* Special symbol for 2nd relocation */ 60 unsigned char r_type3; /* 3rd relocation type */ 61 unsigned char r_type2; /* 2nd relocation type */ 62 unsigned char r_type1; /* 1st relocation type */ 63 } _Elf64_Mips_R_Info; 64 65 typedef union 66 { 67 Elf64_Xword r_info_number; 68 _Elf64_Mips_R_Info r_info_fields; 69 } _Elf64_Mips_R_Info_union; 70 71 #define ELF64_MIPS_R_SYM(i) \ 72 ((__extension__ (_Elf64_Mips_R_Info_union)(i)).r_info_fields.r_sym) 73 74 #define ELF64_MIPS_R_TYPE(i) \ 75 ((__extension__ (_Elf64_Mips_R_Info_union)(i)).r_info_fields.r_type1) 76 77 #if KERNEL_ELFDATA != HOST_ELFDATA 78 79 static inline void __endian(const void *src, void *dest, unsigned int size) 80 { 81 unsigned int i; 82 for (i = 0; i < size; i++) 83 ((unsigned char*)dest)[i] = ((unsigned char*)src)[size - i-1]; 84 } 85 86 #define TO_NATIVE(x) \ 87 ({ \ 88 typeof(x) __x; \ 89 __endian(&(x), &(__x), sizeof(__x)); \ 90 __x; \ 91 }) 92 93 #else /* endianness matches */ 94 95 #define TO_NATIVE(x) (x) 96 97 #endif 98 99 #define NOFAIL(ptr) do_nofail((ptr), #ptr) 100 void *do_nofail(void *ptr, const char *expr); 101 102 struct buffer { 103 char *p; 104 int pos; 105 int size; 106 }; 107 108 void __attribute__((format(printf, 2, 3))) 109 buf_printf(struct buffer *buf, const char *fmt, ...); 110 111 void 112 buf_write(struct buffer *buf, const char *s, int len); 113 114 struct module { 115 struct list_head list; 116 struct list_head exported_symbols; 117 struct list_head unresolved_symbols; 118 bool is_gpl_compatible; 119 bool from_dump; /* true if module was loaded from *.symvers */ 120 bool is_vmlinux; 121 bool seen; 122 bool has_init; 123 bool has_cleanup; 124 struct buffer dev_table_buf; 125 char srcversion[25]; 126 // Missing namespace dependencies 127 struct list_head missing_namespaces; 128 // Actual imported namespaces 129 struct list_head imported_namespaces; 130 char name[]; 131 }; 132 133 struct elf_info { 134 size_t size; 135 Elf_Ehdr *hdr; 136 Elf_Shdr *sechdrs; 137 Elf_Sym *symtab_start; 138 Elf_Sym *symtab_stop; 139 char *strtab; 140 char *modinfo; 141 unsigned int modinfo_len; 142 143 /* support for 32bit section numbers */ 144 145 unsigned int num_sections; /* max_secindex + 1 */ 146 unsigned int secindex_strings; 147 /* if Nth symbol table entry has .st_shndx = SHN_XINDEX, 148 * take shndx from symtab_shndx_start[N] instead */ 149 Elf32_Word *symtab_shndx_start; 150 Elf32_Word *symtab_shndx_stop; 151 }; 152 153 static inline int is_shndx_special(unsigned int i) 154 { 155 return i != SHN_XINDEX && i >= SHN_LORESERVE && i <= SHN_HIRESERVE; 156 } 157 158 /* 159 * Move reserved section indices SHN_LORESERVE..SHN_HIRESERVE out of 160 * the way to -256..-1, to avoid conflicting with real section 161 * indices. 162 */ 163 #define SPECIAL(i) ((i) - (SHN_HIRESERVE + 1)) 164 165 /* Accessor for sym->st_shndx, hides ugliness of "64k sections" */ 166 static inline unsigned int get_secindex(const struct elf_info *info, 167 const Elf_Sym *sym) 168 { 169 if (is_shndx_special(sym->st_shndx)) 170 return SPECIAL(sym->st_shndx); 171 if (sym->st_shndx != SHN_XINDEX) 172 return sym->st_shndx; 173 return info->symtab_shndx_start[sym - info->symtab_start]; 174 } 175 176 /* file2alias.c */ 177 void handle_moddevtable(struct module *mod, struct elf_info *info, 178 Elf_Sym *sym, const char *symname); 179 void add_moddevtable(struct buffer *buf, struct module *mod); 180 181 /* sumversion.c */ 182 void get_src_version(const char *modname, char sum[], unsigned sumlen); 183 184 /* from modpost.c */ 185 char *read_text_file(const char *filename); 186 char *get_line(char **stringp); 187 188 enum loglevel { 189 LOG_WARN, 190 LOG_ERROR, 191 LOG_FATAL 192 }; 193 194 void modpost_log(enum loglevel loglevel, const char *fmt, ...); 195 196 /* 197 * warn - show the given message, then let modpost continue running, still 198 * allowing modpost to exit successfully. This should be used when 199 * we still allow to generate vmlinux and modules. 200 * 201 * error - show the given message, then let modpost continue running, but fail 202 * in the end. This should be used when we should stop building vmlinux 203 * or modules, but we can continue running modpost to catch as many 204 * issues as possible. 205 * 206 * fatal - show the given message, and bail out immediately. This should be 207 * used when there is no point to continue running modpost. 208 */ 209 #define warn(fmt, args...) modpost_log(LOG_WARN, fmt, ##args) 210 #define error(fmt, args...) modpost_log(LOG_ERROR, fmt, ##args) 211 #define fatal(fmt, args...) modpost_log(LOG_FATAL, fmt, ##args) 212