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_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. */
56typedef 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
65typedef 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
79static 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
101#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
102
103void *do_nofail(void *ptr, const char *expr);
104
105struct buffer {
106 char *p;
107 int pos;
108 int size;
109};
110
111void __attribute__((format(printf, 2, 3)))
112buf_printf(struct buffer *buf, const char *fmt, ...);
113
114void
115buf_write(struct buffer *buf, const char *s, int len);
116
117struct module {
118 struct list_head list;
119 struct list_head exported_symbols;
120 struct list_head unresolved_symbols;
121 bool is_gpl_compatible;
122 bool from_dump; /* true if module was loaded from *.symvers */
123 bool is_vmlinux;
124 bool seen;
125 bool has_init;
126 bool has_cleanup;
127 struct buffer dev_table_buf;
128 char srcversion[25];
129 // Missing namespace dependencies
130 struct list_head missing_namespaces;
131 // Actual imported namespaces
132 struct list_head imported_namespaces;
133 char name[];
134};
135
136struct elf_info {
137 size_t size;
138 Elf_Ehdr *hdr;
139 Elf_Shdr *sechdrs;
140 Elf_Sym *symtab_start;
141 Elf_Sym *symtab_stop;
142 char *strtab;
143 char *modinfo;
144 unsigned int modinfo_len;
145
146 /* support for 32bit section numbers */
147
148 unsigned int num_sections; /* max_secindex + 1 */
149 unsigned int secindex_strings;
150 /* if Nth symbol table entry has .st_shndx = SHN_XINDEX,
151 * take shndx from symtab_shndx_start[N] instead */
152 Elf32_Word *symtab_shndx_start;
153 Elf32_Word *symtab_shndx_stop;
154};
155
156static inline int is_shndx_special(unsigned int i)
157{
158 return i != SHN_XINDEX && i >= SHN_LORESERVE && i <= SHN_HIRESERVE;
159}
160
161/*
162 * Move reserved section indices SHN_LORESERVE..SHN_HIRESERVE out of
163 * the way to -256..-1, to avoid conflicting with real section
164 * indices.
165 */
166#define SPECIAL(i) ((i) - (SHN_HIRESERVE + 1))
167
168/* Accessor for sym->st_shndx, hides ugliness of "64k sections" */
169static inline unsigned int get_secindex(const struct elf_info *info,
170 const Elf_Sym *sym)
171{
172 if (is_shndx_special(sym->st_shndx))
173 return SPECIAL(sym->st_shndx);
174 if (sym->st_shndx != SHN_XINDEX)
175 return sym->st_shndx;
176 return info->symtab_shndx_start[sym - info->symtab_start];
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);
190
191enum loglevel {
192 LOG_WARN,
193 LOG_ERROR,
194 LOG_FATAL
195};
196
197void modpost_log(enum loglevel loglevel, const char *fmt, ...);
198
199/*
200 * warn - show the given message, then let modpost continue running, still
201 * allowing modpost to exit successfully. This should be used when
202 * we still allow to generate vmlinux and modules.
203 *
204 * error - show the given message, then let modpost continue running, but fail
205 * in the end. This should be used when we should stop building vmlinux
206 * or modules, but we can continue running modpost to catch as many
207 * issues as possible.
208 *
209 * fatal - show the given message, and bail out immediately. This should be
210 * used when there is no point to continue running modpost.
211 */
212#define warn(fmt, args...) modpost_log(LOG_WARN, fmt, ##args)
213#define error(fmt, args...) modpost_log(LOG_ERROR, fmt, ##args)
214#define fatal(fmt, args...) modpost_log(LOG_FATAL, fmt, ##args)