/
linkage.h
151 lines (125 loc) · 4.03 KB
/
linkage.h
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_LINKAGE_H
#define _ASM_X86_LINKAGE_H
#include <linux/stringify.h>
#include <asm/ibt.h>
#undef notrace
#define notrace __attribute__((no_instrument_function))
#ifdef CONFIG_64BIT
/*
* The generic version tends to create spurious ENDBR instructions under
* certain conditions.
*/
#define _THIS_IP_ ({ unsigned long __here; asm ("lea 0(%%rip), %0" : "=r" (__here)); __here; })
#endif
#ifdef CONFIG_X86_32
#define asmlinkage CPP_ASMLINKAGE __attribute__((regparm(0)))
#endif /* CONFIG_X86_32 */
#define __ALIGN .balign CONFIG_FUNCTION_ALIGNMENT, 0x90;
#define __ALIGN_STR __stringify(__ALIGN)
#if defined(CONFIG_CALL_PADDING) && !defined(__DISABLE_EXPORTS) && !defined(BUILD_VDSO)
#define FUNCTION_PADDING .skip CONFIG_FUNCTION_ALIGNMENT, 0x90;
#else
#define FUNCTION_PADDING
#endif
#if (CONFIG_FUNCTION_ALIGNMENT > 8) && !defined(__DISABLE_EXPORTS) && !defined(BUILD_VDSO)
# define __FUNC_ALIGN __ALIGN; FUNCTION_PADDING
#else
# define __FUNC_ALIGN __ALIGN
#endif
#define ASM_FUNC_ALIGN __stringify(__FUNC_ALIGN)
#define SYM_F_ALIGN __FUNC_ALIGN
#ifdef __ASSEMBLY__
#if defined(CONFIG_MITIGATION_RETHUNK) && !defined(__DISABLE_EXPORTS) && !defined(BUILD_VDSO)
#define RET jmp __x86_return_thunk
#else /* CONFIG_MITIGATION_RETPOLINE */
#ifdef CONFIG_MITIGATION_SLS
#define RET ret; int3
#else
#define RET ret
#endif
#endif /* CONFIG_MITIGATION_RETPOLINE */
#else /* __ASSEMBLY__ */
#if defined(CONFIG_MITIGATION_RETHUNK) && !defined(__DISABLE_EXPORTS) && !defined(BUILD_VDSO)
#define ASM_RET "jmp __x86_return_thunk\n\t"
#else /* CONFIG_MITIGATION_RETPOLINE */
#ifdef CONFIG_MITIGATION_SLS
#define ASM_RET "ret; int3\n\t"
#else
#define ASM_RET "ret\n\t"
#endif
#endif /* CONFIG_MITIGATION_RETPOLINE */
#endif /* __ASSEMBLY__ */
/*
* Depending on -fpatchable-function-entry=N,N usage (CONFIG_CALL_PADDING) the
* CFI symbol layout changes.
*
* Without CALL_THUNKS:
*
* .align FUNCTION_ALIGNMENT
* __cfi_##name:
* .skip FUNCTION_PADDING, 0x90
* .byte 0xb8
* .long __kcfi_typeid_##name
* name:
*
* With CALL_THUNKS:
*
* .align FUNCTION_ALIGNMENT
* __cfi_##name:
* .byte 0xb8
* .long __kcfi_typeid_##name
* .skip FUNCTION_PADDING, 0x90
* name:
*
* In both cases the whole thing is FUNCTION_ALIGNMENT aligned and sized.
*/
#ifdef CONFIG_CALL_PADDING
#define CFI_PRE_PADDING
#define CFI_POST_PADDING .skip CONFIG_FUNCTION_PADDING_BYTES, 0x90;
#else
#define CFI_PRE_PADDING .skip CONFIG_FUNCTION_PADDING_BYTES, 0x90;
#define CFI_POST_PADDING
#endif
#define __CFI_TYPE(name) \
SYM_START(__cfi_##name, SYM_L_LOCAL, SYM_A_NONE) \
CFI_PRE_PADDING \
.byte 0xb8 ASM_NL \
.long __kcfi_typeid_##name ASM_NL \
CFI_POST_PADDING \
SYM_FUNC_END(__cfi_##name)
/* UML needs to be able to override memcpy() and friends for KASAN. */
#ifdef CONFIG_UML
# define SYM_FUNC_ALIAS_MEMFUNC SYM_FUNC_ALIAS_WEAK
#else
# define SYM_FUNC_ALIAS_MEMFUNC SYM_FUNC_ALIAS
#endif
/* SYM_TYPED_FUNC_START -- use for indirectly called globals, w/ CFI type */
#define SYM_TYPED_FUNC_START(name) \
SYM_TYPED_START(name, SYM_L_GLOBAL, SYM_F_ALIGN) \
ENDBR
/* SYM_FUNC_START -- use for global functions */
#define SYM_FUNC_START(name) \
SYM_START(name, SYM_L_GLOBAL, SYM_F_ALIGN) \
ENDBR
/* SYM_FUNC_START_NOALIGN -- use for global functions, w/o alignment */
#define SYM_FUNC_START_NOALIGN(name) \
SYM_START(name, SYM_L_GLOBAL, SYM_A_NONE) \
ENDBR
/* SYM_FUNC_START_LOCAL -- use for local functions */
#define SYM_FUNC_START_LOCAL(name) \
SYM_START(name, SYM_L_LOCAL, SYM_F_ALIGN) \
ENDBR
/* SYM_FUNC_START_LOCAL_NOALIGN -- use for local functions, w/o alignment */
#define SYM_FUNC_START_LOCAL_NOALIGN(name) \
SYM_START(name, SYM_L_LOCAL, SYM_A_NONE) \
ENDBR
/* SYM_FUNC_START_WEAK -- use for weak functions */
#define SYM_FUNC_START_WEAK(name) \
SYM_START(name, SYM_L_WEAK, SYM_F_ALIGN) \
ENDBR
/* SYM_FUNC_START_WEAK_NOALIGN -- use for weak functions, w/o alignment */
#define SYM_FUNC_START_WEAK_NOALIGN(name) \
SYM_START(name, SYM_L_WEAK, SYM_A_NONE) \
ENDBR
#endif /* _ASM_X86_LINKAGE_H */