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1/* SPDX-License-Identifier: GPL-2.0 */ 2#include <stdio.h> 3#include <stdlib.h> 4#include <stdarg.h> 5#include <string.h> 6#include <sys/types.h> 7#include <sys/stat.h> 8#include <sys/mman.h> 9#include <fcntl.h> 10#include <unistd.h> 11#include <elf.h> 12 13#include "elfconfig.h" 14 15/* On BSD-alike OSes elf.h defines these according to host's word size */ 16#undef ELF_ST_BIND 17#undef ELF_ST_TYPE 18#undef ELF_R_SYM 19#undef ELF_R_TYPE 20 21#if KERNEL_ELFCLASS == ELFCLASS32 22 23#define Elf_Ehdr Elf32_Ehdr 24#define Elf_Shdr Elf32_Shdr 25#define Elf_Sym Elf32_Sym 26#define Elf_Addr Elf32_Addr 27#define Elf_Sword Elf64_Sword 28#define Elf_Section Elf32_Half 29#define ELF_ST_BIND ELF32_ST_BIND 30#define ELF_ST_TYPE ELF32_ST_TYPE 31 32#define Elf_Rel Elf32_Rel 33#define Elf_Rela Elf32_Rela 34#define ELF_R_SYM ELF32_R_SYM 35#define ELF_R_TYPE ELF32_R_TYPE 36#else 37 38#define Elf_Ehdr Elf64_Ehdr 39#define Elf_Shdr Elf64_Shdr 40#define Elf_Sym Elf64_Sym 41#define Elf_Addr Elf64_Addr 42#define Elf_Sword Elf64_Sxword 43#define Elf_Section Elf64_Half 44#define ELF_ST_BIND ELF64_ST_BIND 45#define ELF_ST_TYPE ELF64_ST_TYPE 46 47#define Elf_Rel Elf64_Rel 48#define Elf_Rela Elf64_Rela 49#define ELF_R_SYM ELF64_R_SYM 50#define ELF_R_TYPE ELF64_R_TYPE 51#endif 52 53/* The 64-bit MIPS ELF ABI uses an unusual reloc format. */ 54typedef struct 55{ 56 Elf32_Word r_sym; /* Symbol index */ 57 unsigned char r_ssym; /* Special symbol for 2nd relocation */ 58 unsigned char r_type3; /* 3rd relocation type */ 59 unsigned char r_type2; /* 2nd relocation type */ 60 unsigned char r_type1; /* 1st relocation type */ 61} _Elf64_Mips_R_Info; 62 63typedef union 64{ 65 Elf64_Xword r_info_number; 66 _Elf64_Mips_R_Info r_info_fields; 67} _Elf64_Mips_R_Info_union; 68 69#define ELF64_MIPS_R_SYM(i) \ 70 ((__extension__ (_Elf64_Mips_R_Info_union)(i)).r_info_fields.r_sym) 71 72#define ELF64_MIPS_R_TYPE(i) \ 73 ((__extension__ (_Elf64_Mips_R_Info_union)(i)).r_info_fields.r_type1) 74 75#if KERNEL_ELFDATA != HOST_ELFDATA 76 77static inline void __endian(const void *src, void *dest, unsigned int size) 78{ 79 unsigned int i; 80 for (i = 0; i < size; i++) 81 ((unsigned char*)dest)[i] = ((unsigned char*)src)[size - i-1]; 82} 83 84#define TO_NATIVE(x) \ 85({ \ 86 typeof(x) __x; \ 87 __endian(&(x), &(__x), sizeof(__x)); \ 88 __x; \ 89}) 90 91#else /* endianness matches */ 92 93#define TO_NATIVE(x) (x) 94 95#endif 96 97#define NOFAIL(ptr) do_nofail((ptr), #ptr) 98void *do_nofail(void *ptr, const char *expr); 99 100struct buffer { 101 char *p; 102 int pos; 103 int size; 104}; 105 106void __attribute__((format(printf, 2, 3))) 107buf_printf(struct buffer *buf, const char *fmt, ...); 108 109void 110buf_write(struct buffer *buf, const char *s, int len); 111 112struct namespace_list { 113 struct namespace_list *next; 114 char namespace[0]; 115}; 116 117struct module { 118 struct module *next; 119 const char *name; 120 int gpl_compatible; 121 struct symbol *unres; 122 int seen; 123 int skip; 124 int has_init; 125 int has_cleanup; 126 struct buffer dev_table_buf; 127 char srcversion[25]; 128 int is_dot_o; 129 // Required namespace dependencies 130 struct namespace_list *required_namespaces; 131 // Actual imported namespaces 132 struct namespace_list *imported_namespaces; 133}; 134 135struct elf_info { 136 unsigned long size; 137 Elf_Ehdr *hdr; 138 Elf_Shdr *sechdrs; 139 Elf_Sym *symtab_start; 140 Elf_Sym *symtab_stop; 141 Elf_Section export_sec; 142 Elf_Section export_unused_sec; 143 Elf_Section export_gpl_sec; 144 Elf_Section export_unused_gpl_sec; 145 Elf_Section export_gpl_future_sec; 146 char *ksymtab_strings; 147 char *strtab; 148 char *modinfo; 149 unsigned int modinfo_len; 150 151 /* support for 32bit section numbers */ 152 153 unsigned int num_sections; /* max_secindex + 1 */ 154 unsigned int secindex_strings; 155 /* if Nth symbol table entry has .st_shndx = SHN_XINDEX, 156 * take shndx from symtab_shndx_start[N] instead */ 157 Elf32_Word *symtab_shndx_start; 158 Elf32_Word *symtab_shndx_stop; 159}; 160 161static inline int is_shndx_special(unsigned int i) 162{ 163 return i != SHN_XINDEX && i >= SHN_LORESERVE && i <= SHN_HIRESERVE; 164} 165 166/* 167 * Move reserved section indices SHN_LORESERVE..SHN_HIRESERVE out of 168 * the way to -256..-1, to avoid conflicting with real section 169 * indices. 170 */ 171#define SPECIAL(i) ((i) - (SHN_HIRESERVE + 1)) 172 173/* Accessor for sym->st_shndx, hides ugliness of "64k sections" */ 174static inline unsigned int get_secindex(const struct elf_info *info, 175 const Elf_Sym *sym) 176{ 177 if (is_shndx_special(sym->st_shndx)) 178 return SPECIAL(sym->st_shndx); 179 if (sym->st_shndx != SHN_XINDEX) 180 return sym->st_shndx; 181 return info->symtab_shndx_start[sym - info->symtab_start]; 182} 183 184/* file2alias.c */ 185extern unsigned int cross_build; 186void handle_moddevtable(struct module *mod, struct elf_info *info, 187 Elf_Sym *sym, const char *symname); 188void add_moddevtable(struct buffer *buf, struct module *mod); 189 190/* sumversion.c */ 191void maybe_frob_rcs_version(const char *modfilename, 192 char *version, 193 void *modinfo, 194 unsigned long modinfo_offset); 195void get_src_version(const char *modname, char sum[], unsigned sumlen); 196 197/* from modpost.c */ 198void *grab_file(const char *filename, unsigned long *size); 199char* get_next_line(unsigned long *pos, void *file, unsigned long size); 200void release_file(void *file, unsigned long size); 201 202void fatal(const char *fmt, ...); 203void warn(const char *fmt, ...); 204void merror(const char *fmt, ...);