Linux kernel mirror (for testing)
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linux
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_Section Elf32_Half
30#define ELF_ST_BIND ELF32_ST_BIND
31#define ELF_ST_TYPE ELF32_ST_TYPE
32
33#define Elf_Rel Elf32_Rel
34#define Elf_Rela Elf32_Rela
35#define ELF_R_SYM ELF32_R_SYM
36#define ELF_R_TYPE ELF32_R_TYPE
37#else
38
39#define Elf_Ehdr Elf64_Ehdr
40#define Elf_Shdr Elf64_Shdr
41#define Elf_Sym Elf64_Sym
42#define Elf_Addr Elf64_Addr
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)
98
99#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
100
101void *do_nofail(void *ptr, const char *expr);
102
103struct buffer {
104 char *p;
105 int pos;
106 int size;
107};
108
109void __attribute__((format(printf, 2, 3)))
110buf_printf(struct buffer *buf, const char *fmt, ...);
111
112void
113buf_write(struct buffer *buf, const char *s, int len);
114
115struct module {
116 struct list_head list;
117 struct list_head exported_symbols;
118 struct list_head unresolved_symbols;
119 bool is_gpl_compatible;
120 bool from_dump; /* true if module was loaded from *.symvers */
121 bool is_vmlinux;
122 bool seen;
123 bool has_init;
124 bool has_cleanup;
125 struct buffer dev_table_buf;
126 char srcversion[25];
127 // Missing namespace dependencies
128 struct list_head missing_namespaces;
129 // Actual imported namespaces
130 struct list_head imported_namespaces;
131 char name[];
132};
133
134struct elf_info {
135 size_t size;
136 Elf_Ehdr *hdr;
137 Elf_Shdr *sechdrs;
138 Elf_Sym *symtab_start;
139 Elf_Sym *symtab_stop;
140 unsigned int export_symbol_secndx; /* .export_symbol section */
141 char *strtab;
142 char *modinfo;
143 unsigned int modinfo_len;
144
145 /* support for 32bit section numbers */
146
147 unsigned int num_sections; /* max_secindex + 1 */
148 unsigned int secindex_strings;
149 /* if Nth symbol table entry has .st_shndx = SHN_XINDEX,
150 * take shndx from symtab_shndx_start[N] instead */
151 Elf32_Word *symtab_shndx_start;
152 Elf32_Word *symtab_shndx_stop;
153};
154
155/* Accessor for sym->st_shndx, hides ugliness of "64k sections" */
156static inline unsigned int get_secindex(const struct elf_info *info,
157 const Elf_Sym *sym)
158{
159 unsigned int index = sym->st_shndx;
160
161 /*
162 * Elf{32,64}_Sym::st_shndx is 2 byte. Big section numbers are available
163 * in the .symtab_shndx section.
164 */
165 if (index == SHN_XINDEX)
166 return info->symtab_shndx_start[sym - info->symtab_start];
167
168 /*
169 * Move reserved section indices SHN_LORESERVE..SHN_HIRESERVE out of
170 * the way to UINT_MAX-255..UINT_MAX, to avoid conflicting with real
171 * section indices.
172 */
173 if (index >= SHN_LORESERVE && index <= SHN_HIRESERVE)
174 return index - SHN_HIRESERVE - 1;
175
176 return index;
177}
178
179/* file2alias.c */
180void handle_moddevtable(struct module *mod, struct elf_info *info,
181 Elf_Sym *sym, const char *symname);
182void add_moddevtable(struct buffer *buf, struct module *mod);
183
184/* sumversion.c */
185void get_src_version(const char *modname, char sum[], unsigned sumlen);
186
187/* from modpost.c */
188char *read_text_file(const char *filename);
189char *get_line(char **stringp);
190void *sym_get_data(const struct elf_info *info, const Elf_Sym *sym);
191
192enum loglevel {
193 LOG_WARN,
194 LOG_ERROR,
195 LOG_FATAL
196};
197
198void modpost_log(enum loglevel loglevel, const char *fmt, ...);
199
200/*
201 * warn - show the given message, then let modpost continue running, still
202 * allowing modpost to exit successfully. This should be used when
203 * we still allow to generate vmlinux and modules.
204 *
205 * error - show the given message, then let modpost continue running, but fail
206 * in the end. This should be used when we should stop building vmlinux
207 * or modules, but we can continue running modpost to catch as many
208 * issues as possible.
209 *
210 * fatal - show the given message, and bail out immediately. This should be
211 * used when there is no point to continue running modpost.
212 */
213#define warn(fmt, args...) modpost_log(LOG_WARN, fmt, ##args)
214#define error(fmt, args...) modpost_log(LOG_ERROR, fmt, ##args)
215#define fatal(fmt, args...) modpost_log(LOG_FATAL, fmt, ##args)