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
|
// SPDX-License-Identifier: GPL-2.0
#include <vmlinux.h>
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>
#include "bpf_misc.h"
#include "bpf_experimental.h"
SEC("?tc")
__failure __msg("1 bpf_preempt_enable is missing")
int preempt_lock_missing_1(struct __sk_buff *ctx)
{
bpf_preempt_disable();
return 0;
}
SEC("?tc")
__failure __msg("2 bpf_preempt_enable(s) are missing")
int preempt_lock_missing_2(struct __sk_buff *ctx)
{
bpf_preempt_disable();
bpf_preempt_disable();
return 0;
}
SEC("?tc")
__failure __msg("3 bpf_preempt_enable(s) are missing")
int preempt_lock_missing_3(struct __sk_buff *ctx)
{
bpf_preempt_disable();
bpf_preempt_disable();
bpf_preempt_disable();
return 0;
}
SEC("?tc")
__failure __msg("1 bpf_preempt_enable is missing")
int preempt_lock_missing_3_minus_2(struct __sk_buff *ctx)
{
bpf_preempt_disable();
bpf_preempt_disable();
bpf_preempt_disable();
bpf_preempt_enable();
bpf_preempt_enable();
return 0;
}
static __noinline void preempt_disable(void)
{
bpf_preempt_disable();
}
static __noinline void preempt_enable(void)
{
bpf_preempt_enable();
}
SEC("?tc")
__failure __msg("1 bpf_preempt_enable is missing")
int preempt_lock_missing_1_subprog(struct __sk_buff *ctx)
{
preempt_disable();
return 0;
}
SEC("?tc")
__failure __msg("2 bpf_preempt_enable(s) are missing")
int preempt_lock_missing_2_subprog(struct __sk_buff *ctx)
{
preempt_disable();
preempt_disable();
return 0;
}
SEC("?tc")
__failure __msg("1 bpf_preempt_enable is missing")
int preempt_lock_missing_2_minus_1_subprog(struct __sk_buff *ctx)
{
preempt_disable();
preempt_disable();
preempt_enable();
return 0;
}
static __noinline void preempt_balance_subprog(void)
{
preempt_disable();
preempt_enable();
}
SEC("?tc")
__success int preempt_balance(struct __sk_buff *ctx)
{
bpf_guard_preempt();
return 0;
}
SEC("?tc")
__success int preempt_balance_subprog_test(struct __sk_buff *ctx)
{
preempt_balance_subprog();
return 0;
}
SEC("?fentry.s/" SYS_PREFIX "sys_getpgid")
__failure __msg("sleepable helper bpf_copy_from_user#")
int preempt_sleepable_helper(void *ctx)
{
u32 data;
bpf_preempt_disable();
bpf_copy_from_user(&data, sizeof(data), NULL);
bpf_preempt_enable();
return 0;
}
int __noinline preempt_global_subprog(void)
{
preempt_balance_subprog();
return 0;
}
SEC("?tc")
__failure __msg("global function calls are not allowed with preemption disabled")
int preempt_global_subprog_test(struct __sk_buff *ctx)
{
preempt_disable();
preempt_global_subprog();
preempt_enable();
return 0;
}
char _license[] SEC("license") = "GPL";
|
