/* SPDX-License-Identifier: GPL-2.0 */
#include <byteswap.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <fcntl.h>
#include <unistd.h>
#include <elf.h>
#include "../../include/linux/module_symbol.h"
#include <list_types.h>
#include "elfconfig.h"
/* On BSD-alike OSes elf.h defines these according to host's word size */
#undef ELF_ST_BIND
#undef ELF_ST_TYPE
#undef ELF_R_SYM
#undef ELF_R_TYPE
#if KERNEL_ELFCLASS == ELFCLASS32
#define Elf_Ehdr Elf32_Ehdr
#define Elf_Shdr Elf32_Shdr
#define Elf_Sym Elf32_Sym
#define Elf_Addr Elf32_Addr
#define Elf_Section Elf32_Half
#define ELF_ST_BIND ELF32_ST_BIND
#define ELF_ST_TYPE ELF32_ST_TYPE
#define Elf_Rel Elf32_Rel
#define Elf_Rela Elf32_Rela
#define ELF_R_SYM ELF32_R_SYM
#define ELF_R_TYPE ELF32_R_TYPE
#else
#define Elf_Ehdr Elf64_Ehdr
#define Elf_Shdr Elf64_Shdr
#define Elf_Sym Elf64_Sym
#define Elf_Addr Elf64_Addr
#define Elf_Section Elf64_Half
#define ELF_ST_BIND ELF64_ST_BIND
#define ELF_ST_TYPE ELF64_ST_TYPE
#define Elf_Rel Elf64_Rel
#define Elf_Rela Elf64_Rela
#define ELF_R_SYM ELF64_R_SYM
#define ELF_R_TYPE ELF64_R_TYPE
#endif
#define bswap(x) \
({ \
_Static_assert(sizeof(x) == 1 || sizeof(x) == 2 || \
sizeof(x) == 4 || sizeof(x) == 8, "bug"); \
(typeof(x))(sizeof(x) == 2 ? bswap_16(x) : \
sizeof(x) == 4 ? bswap_32(x) : \
sizeof(x) == 8 ? bswap_64(x) : \
x); \
})
#if KERNEL_ELFDATA != HOST_ELFDATA
#define TO_NATIVE(x) (bswap(x))
#else /* endianness matches */
#define TO_NATIVE(x) (x)
#endif
#define NOFAIL(ptr) do_nofail((ptr), #ptr)
#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
void *do_nofail(void *ptr, const char *expr);
struct buffer {
char *p;
int pos;
int size;
};
void __attribute__((format(printf, 2, 3)))
buf_printf(struct buffer *buf, const char *fmt, ...);
void
buf_write(struct buffer *buf, const char *s, int len);
struct module {
struct list_head list;
struct list_head exported_symbols;
struct list_head unresolved_symbols;
bool is_gpl_compatible;
bool from_dump; /* true if module was loaded from *.symvers */
bool is_vmlinux;
bool seen;
bool has_init;
bool has_cleanup;
struct buffer dev_table_buf;
char srcversion[25];
// Missing namespace dependencies
struct list_head missing_namespaces;
// Actual imported namespaces
struct list_head imported_namespaces;
char name[];
};
struct elf_info {
size_t size;
Elf_Ehdr *hdr;
Elf_Shdr *sechdrs;
Elf_Sym *symtab_start;
Elf_Sym *symtab_stop;
unsigned int export_symbol_secndx; /* .export_symbol section */
char *strtab;
char *modinfo;
unsigned int modinfo_len;
/* support for 32bit section numbers */
unsigned int num_sections; /* max_secindex + 1 */
unsigned int secindex_strings;
/* if Nth symbol table entry has .st_shndx = SHN_XINDEX,
* take shndx from symtab_shndx_start[N] instead */
Elf32_Word *symtab_shndx_start;
Elf32_Word *symtab_shndx_stop;
struct symsearch *symsearch;
};
/* Accessor for sym->st_shndx, hides ugliness of "64k sections" */
static inline unsigned int get_secindex(const struct elf_info *info,
const Elf_Sym *sym)
{
unsigned int index = sym->st_shndx;
/*
* Elf{32,64}_Sym::st_shndx is 2 byte. Big section numbers are available
* in the .symtab_shndx section.
*/
if (index == SHN_XINDEX)
return info->symtab_shndx_start[sym - info->symtab_start];
/*
* Move reserved section indices SHN_LORESERVE..SHN_HIRESERVE out of
* the way to UINT_MAX-255..UINT_MAX, to avoid conflicting with real
* section indices.
*/
if (index >= SHN_LORESERVE && index <= SHN_HIRESERVE)
return index - SHN_HIRESERVE - 1;
return index;
}
/*
* If there's no name there, ignore it; likewise, ignore it if it's
* one of the magic symbols emitted used by current tools.
*
* Internal symbols created by tools should be ignored by modpost.
*/
static inline bool is_valid_name(struct elf_info *elf, Elf_Sym *sym)
{
const char *name = elf->strtab + sym->st_name;
if (!name || !strlen(name))
return false;
return !is_mapping_symbol(name);
}
/* symsearch.c */
void symsearch_init(struct elf_info *elf);
void symsearch_finish(struct elf_info *elf);
Elf_Sym *symsearch_find_nearest(struct elf_info *elf, Elf_Addr addr,
unsigned int secndx, bool allow_negative,
Elf_Addr min_distance);
/* file2alias.c */
void handle_moddevtable(struct module *mod, struct elf_info *info,
Elf_Sym *sym, const char *symname);
void add_moddevtable(struct buffer *buf, struct module *mod);
/* sumversion.c */
void get_src_version(const char *modname, char sum[], unsigned sumlen);
/* from modpost.c */
char *read_text_file(const char *filename);
char *get_line(char **stringp);
void *sym_get_data(const struct elf_info *info, const Elf_Sym *sym);
enum loglevel {
LOG_WARN,
LOG_ERROR,
};
void __attribute__((format(printf, 2, 3)))
modpost_log(enum loglevel loglevel, const char *fmt, ...);
/*
* warn - show the given message, then let modpost continue running, still
* allowing modpost to exit successfully. This should be used when
* we still allow to generate vmlinux and modules.
*
* error - show the given message, then let modpost continue running, but fail
* in the end. This should be used when we should stop building vmlinux
* or modules, but we can continue running modpost to catch as many
* issues as possible.
*
* fatal - show the given message, and bail out immediately. This should be
* used when there is no point to continue running modpost.
*/
#define warn(fmt, args...) modpost_log(LOG_WARN, fmt, ##args)
#define error(fmt, args...) modpost_log(LOG_ERROR, fmt, ##args)
#define fatal(fmt, args...) do { error(fmt, ##args); exit(1); } while (1)
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