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
|
#ifndef _ASM_X86_PKEYS_H
#define _ASM_X86_PKEYS_H
#define arch_max_pkey() (boot_cpu_has(X86_FEATURE_OSPKE) ? 16 : 1)
extern int arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
unsigned long init_val);
/*
* Try to dedicate one of the protection keys to be used as an
* execute-only protection key.
*/
extern int __execute_only_pkey(struct mm_struct *mm);
static inline int execute_only_pkey(struct mm_struct *mm)
{
if (!boot_cpu_has(X86_FEATURE_OSPKE))
return 0;
return __execute_only_pkey(mm);
}
extern int __arch_override_mprotect_pkey(struct vm_area_struct *vma,
int prot, int pkey);
static inline int arch_override_mprotect_pkey(struct vm_area_struct *vma,
int prot, int pkey)
{
if (!boot_cpu_has(X86_FEATURE_OSPKE))
return 0;
return __arch_override_mprotect_pkey(vma, prot, pkey);
}
extern int __arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
unsigned long init_val);
#define ARCH_VM_PKEY_FLAGS (VM_PKEY_BIT0 | VM_PKEY_BIT1 | VM_PKEY_BIT2 | VM_PKEY_BIT3)
#define mm_pkey_allocation_map(mm) (mm->context.pkey_allocation_map)
#define mm_set_pkey_allocated(mm, pkey) do { \
mm_pkey_allocation_map(mm) |= (1U << pkey); \
} while (0)
#define mm_set_pkey_free(mm, pkey) do { \
mm_pkey_allocation_map(mm) &= ~(1U << pkey); \
} while (0)
static inline
bool mm_pkey_is_allocated(struct mm_struct *mm, int pkey)
{
return mm_pkey_allocation_map(mm) & (1U << pkey);
}
/*
* Returns a positive, 4-bit key on success, or -1 on failure.
*/
static inline
int mm_pkey_alloc(struct mm_struct *mm)
{
/*
* Note: this is the one and only place we make sure
* that the pkey is valid as far as the hardware is
* concerned. The rest of the kernel trusts that
* only good, valid pkeys come out of here.
*/
u16 all_pkeys_mask = ((1U << arch_max_pkey()) - 1);
int ret;
/*
* Are we out of pkeys? We must handle this specially
* because ffz() behavior is undefined if there are no
* zeros.
*/
if (mm_pkey_allocation_map(mm) == all_pkeys_mask)
return -1;
ret = ffz(mm_pkey_allocation_map(mm));
mm_set_pkey_allocated(mm, ret);
return ret;
}
static inline
int mm_pkey_free(struct mm_struct *mm, int pkey)
{
/*
* pkey 0 is special, always allocated and can never
* be freed.
*/
if (!pkey)
return -EINVAL;
if (!mm_pkey_is_allocated(mm, pkey))
return -EINVAL;
mm_set_pkey_free(mm, pkey);
return 0;
}
extern int arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
unsigned long init_val);
extern int __arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
unsigned long init_val);
#endif /*_ASM_X86_PKEYS_H */
|
