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
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
|
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _PKEYS_X86_H
#define _PKEYS_X86_H
#ifdef __i386__
#ifndef SYS_mprotect_key
# define SYS_mprotect_key 380
#endif
#ifndef SYS_pkey_alloc
# define SYS_pkey_alloc 381
# define SYS_pkey_free 382
#endif
#define REG_IP_IDX REG_EIP
#define si_pkey_offset 0x14
#else
#ifndef SYS_mprotect_key
# define SYS_mprotect_key 329
#endif
#ifndef SYS_pkey_alloc
# define SYS_pkey_alloc 330
# define SYS_pkey_free 331
#endif
#define REG_IP_IDX REG_RIP
#define si_pkey_offset 0x20
#endif
#ifndef PKEY_DISABLE_ACCESS
# define PKEY_DISABLE_ACCESS 0x1
#endif
#ifndef PKEY_DISABLE_WRITE
# define PKEY_DISABLE_WRITE 0x2
#endif
#define NR_PKEYS 16
#define NR_RESERVED_PKEYS 2 /* pkey-0 and exec-only-pkey */
#define PKEY_BITS_PER_PKEY 2
#define HPAGE_SIZE (1UL<<21)
#define PAGE_SIZE 4096
#define MB (1<<20)
static inline void __page_o_noops(void)
{
/* 8-bytes of instruction * 512 bytes = 1 page */
asm(".rept 512 ; nopl 0x7eeeeeee(%eax) ; .endr");
}
static inline u64 __read_pkey_reg(void)
{
unsigned int eax, edx;
unsigned int ecx = 0;
unsigned pkey_reg;
asm volatile(".byte 0x0f,0x01,0xee\n\t"
: "=a" (eax), "=d" (edx)
: "c" (ecx));
pkey_reg = eax;
return pkey_reg;
}
static inline void __write_pkey_reg(u64 pkey_reg)
{
unsigned int eax = pkey_reg;
unsigned int ecx = 0;
unsigned int edx = 0;
dprintf4("%s() changing %016llx to %016llx\n", __func__,
__read_pkey_reg(), pkey_reg);
asm volatile(".byte 0x0f,0x01,0xef\n\t"
: : "a" (eax), "c" (ecx), "d" (edx));
assert(pkey_reg == __read_pkey_reg());
}
static inline void __cpuid(unsigned int *eax, unsigned int *ebx,
unsigned int *ecx, unsigned int *edx)
{
/* ecx is often an input as well as an output. */
asm volatile(
"cpuid;"
: "=a" (*eax),
"=b" (*ebx),
"=c" (*ecx),
"=d" (*edx)
: "0" (*eax), "2" (*ecx));
}
/* Intel-defined CPU features, CPUID level 0x00000007:0 (ecx) */
#define X86_FEATURE_PKU (1<<3) /* Protection Keys for Userspace */
#define X86_FEATURE_OSPKE (1<<4) /* OS Protection Keys Enable */
static inline int cpu_has_pkeys(void)
{
unsigned int eax;
unsigned int ebx;
unsigned int ecx;
unsigned int edx;
eax = 0x7;
ecx = 0x0;
__cpuid(&eax, &ebx, &ecx, &edx);
if (!(ecx & X86_FEATURE_PKU)) {
dprintf2("cpu does not have PKU\n");
return 0;
}
if (!(ecx & X86_FEATURE_OSPKE)) {
dprintf2("cpu does not have OSPKE\n");
return 0;
}
return 1;
}
static inline u32 pkey_bit_position(int pkey)
{
return pkey * PKEY_BITS_PER_PKEY;
}
#define XSTATE_PKEY_BIT (9)
#define XSTATE_PKEY 0x200
#define XSTATE_BV_OFFSET 512
int pkey_reg_xstate_offset(void)
{
unsigned int eax;
unsigned int ebx;
unsigned int ecx;
unsigned int edx;
int xstate_offset;
int xstate_size;
unsigned long XSTATE_CPUID = 0xd;
int leaf;
/* assume that XSTATE_PKEY is set in XCR0 */
leaf = XSTATE_PKEY_BIT;
{
eax = XSTATE_CPUID;
ecx = leaf;
__cpuid(&eax, &ebx, &ecx, &edx);
if (leaf == XSTATE_PKEY_BIT) {
xstate_offset = ebx;
xstate_size = eax;
}
}
if (xstate_size == 0) {
printf("could not find size/offset of PKEY in xsave state\n");
return 0;
}
return xstate_offset;
}
static inline int get_arch_reserved_keys(void)
{
return NR_RESERVED_PKEYS;
}
void expect_fault_on_read_execonly_key(void *p1, int pkey)
{
int ptr_contents;
ptr_contents = read_ptr(p1);
dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents);
expected_pkey_fault(pkey);
}
void *malloc_pkey_with_mprotect_subpage(long size, int prot, u16 pkey)
{
return PTR_ERR_ENOTSUP;
}
#endif /* _PKEYS_X86_H */
|
