1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * 32-bit compatibility support for ELF format executables and core dumps.
4 *
5 * Copyright (C) 2007 Red Hat, Inc.  All rights reserved.
6 *
7 * Red Hat Author: Roland McGrath.
8 *
9 * This file is used in a 64-bit kernel that wants to support 32-bit ELF.
10 * asm/elf.h is responsible for defining the compat_* and COMPAT_* macros
11 * used below, with definitions appropriate for 32-bit ABI compatibility.
12 *
13 * We use macros to rename the ABI types and machine-dependent
14 * functions used in binfmt_elf.c to compat versions.
15 */
16
17#include <linux/elfcore-compat.h>
18#include <linux/time.h>
19
20#define ELF_COMPAT	1
21
22/*
23 * Rename the basic ELF layout types to refer to the 32-bit class of files.
24 */
25#undef	ELF_CLASS
26#define ELF_CLASS	ELFCLASS32
27
28#undef	elfhdr
29#undef	elf_phdr
30#undef	elf_shdr
31#undef	elf_note
32#undef	elf_addr_t
33#undef	ELF_GNU_PROPERTY_ALIGN
34#define elfhdr		elf32_hdr
35#define elf_phdr	elf32_phdr
36#define elf_shdr	elf32_shdr
37#define elf_note	elf32_note
38#define elf_addr_t	Elf32_Addr
39#define ELF_GNU_PROPERTY_ALIGN	ELF32_GNU_PROPERTY_ALIGN
40
41/*
42 * Some data types as stored in coredump.
43 */
44#define user_long_t		compat_long_t
45#define user_siginfo_t		compat_siginfo_t
46#define copy_siginfo_to_external	copy_siginfo_to_external32
47
48/*
49 * The machine-dependent core note format types are defined in elfcore-compat.h,
50 * which requires asm/elf.h to define compat_elf_gregset_t et al.
51 */
52#define elf_prstatus	compat_elf_prstatus
53#define elf_prstatus_common	compat_elf_prstatus_common
54#define elf_prpsinfo	compat_elf_prpsinfo
55
56#undef ns_to_kernel_old_timeval
57#define ns_to_kernel_old_timeval ns_to_old_timeval32
58
59/*
60 * To use this file, asm/elf.h must define compat_elf_check_arch.
61 * The other following macros can be defined if the compat versions
62 * differ from the native ones, or omitted when they match.
63 */
64
65#undef	elf_check_arch
66#define	elf_check_arch	compat_elf_check_arch
67
68#ifdef	COMPAT_ELF_PLATFORM
69#undef	ELF_PLATFORM
70#define	ELF_PLATFORM		COMPAT_ELF_PLATFORM
71#endif
72
73#ifdef	COMPAT_ELF_HWCAP
74#undef	ELF_HWCAP
75#define	ELF_HWCAP		COMPAT_ELF_HWCAP
76#endif
77
78#ifdef	COMPAT_ELF_HWCAP2
79#undef	ELF_HWCAP2
80#define	ELF_HWCAP2		COMPAT_ELF_HWCAP2
81#endif
82
83#ifdef	COMPAT_ARCH_DLINFO
84#undef	ARCH_DLINFO
85#define	ARCH_DLINFO		COMPAT_ARCH_DLINFO
86#endif
87
88#ifdef	COMPAT_ELF_ET_DYN_BASE
89#undef	ELF_ET_DYN_BASE
90#define	ELF_ET_DYN_BASE		COMPAT_ELF_ET_DYN_BASE
91#endif
92
93#ifdef	COMPAT_ELF_PLAT_INIT
94#undef	ELF_PLAT_INIT
95#define	ELF_PLAT_INIT		COMPAT_ELF_PLAT_INIT
96#endif
97
98#ifdef	COMPAT_SET_PERSONALITY
99#undef	SET_PERSONALITY
100#define	SET_PERSONALITY		COMPAT_SET_PERSONALITY
101#endif
102
103#ifdef	compat_start_thread
104#define COMPAT_START_THREAD(ex, regs, new_ip, new_sp)	\
105	compat_start_thread(regs, new_ip, new_sp)
106#endif
107
108#ifdef	COMPAT_START_THREAD
109#undef	START_THREAD
110#define START_THREAD		COMPAT_START_THREAD
111#endif
112
113#ifdef compat_arch_setup_additional_pages
114#define COMPAT_ARCH_SETUP_ADDITIONAL_PAGES(bprm, ex, interpreter) \
115	compat_arch_setup_additional_pages(bprm, interpreter)
116#endif
117
118#ifdef	COMPAT_ARCH_SETUP_ADDITIONAL_PAGES
119#undef	ARCH_HAS_SETUP_ADDITIONAL_PAGES
120#define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1
121#undef	ARCH_SETUP_ADDITIONAL_PAGES
122#define	ARCH_SETUP_ADDITIONAL_PAGES COMPAT_ARCH_SETUP_ADDITIONAL_PAGES
123#endif
124
125#ifdef	compat_elf_read_implies_exec
126#undef	elf_read_implies_exec
127#define	elf_read_implies_exec compat_elf_read_implies_exec
128#endif
129
130/*
131 * Rename a few of the symbols that binfmt_elf.c will define.
132 * These are all local so the names don't really matter, but it
133 * might make some debugging less confusing not to duplicate them.
134 */
135#define elf_format		compat_elf_format
136#define init_elf_binfmt		init_compat_elf_binfmt
137#define exit_elf_binfmt		exit_compat_elf_binfmt
138#define binfmt_elf_test_cases	compat_binfmt_elf_test_cases
139#define binfmt_elf_test_suite	compat_binfmt_elf_test_suite
140
141/*
142 * We share all the actual code with the native (64-bit) version.
143 */
144#include "binfmt_elf.c"
145