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
|
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright 2020 Google LLC.
*/
#include "vmlinux.h"
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>
#include <errno.h>
struct {
__uint(type, BPF_MAP_TYPE_ARRAY);
__uint(max_entries, 1);
__type(key, __u32);
__type(value, __u64);
} array SEC(".maps");
struct {
__uint(type, BPF_MAP_TYPE_HASH);
__uint(max_entries, 1);
__type(key, __u32);
__type(value, __u64);
} hash SEC(".maps");
struct {
__uint(type, BPF_MAP_TYPE_LRU_HASH);
__uint(max_entries, 1);
__type(key, __u32);
__type(value, __u64);
} lru_hash SEC(".maps");
char _license[] SEC("license") = "GPL";
int monitored_pid = 0;
int mprotect_count = 0;
int bprm_count = 0;
SEC("lsm/file_mprotect")
int BPF_PROG(test_int_hook, struct vm_area_struct *vma,
unsigned long reqprot, unsigned long prot, int ret)
{
if (ret != 0)
return ret;
__u32 pid = bpf_get_current_pid_tgid() >> 32;
int is_stack = 0;
is_stack = (vma->vm_start <= vma->vm_mm->start_stack &&
vma->vm_end >= vma->vm_mm->start_stack);
if (is_stack && monitored_pid == pid) {
mprotect_count++;
ret = -EPERM;
}
return ret;
}
SEC("lsm.s/bprm_committed_creds")
int BPF_PROG(test_void_hook, struct linux_binprm *bprm)
{
__u32 pid = bpf_get_current_pid_tgid() >> 32;
char args[64];
__u32 key = 0;
__u64 *value;
if (monitored_pid == pid)
bprm_count++;
bpf_copy_from_user(args, sizeof(args), (void *)bprm->vma->vm_mm->arg_start);
bpf_copy_from_user(args, sizeof(args), (void *)bprm->mm->arg_start);
value = bpf_map_lookup_elem(&array, &key);
if (value)
*value = 0;
value = bpf_map_lookup_elem(&hash, &key);
if (value)
*value = 0;
value = bpf_map_lookup_elem(&lru_hash, &key);
if (value)
*value = 0;
return 0;
}
SEC("lsm/task_free") /* lsm/ is ok, lsm.s/ fails */
int BPF_PROG(test_task_free, struct task_struct *task)
{
return 0;
}
int copy_test = 0;
SEC("fentry.s/__x64_sys_setdomainname")
int BPF_PROG(test_sys_setdomainname, struct pt_regs *regs)
{
void *ptr = (void *)PT_REGS_PARM1(regs);
int len = PT_REGS_PARM2(regs);
int buf = 0;
long ret;
ret = bpf_copy_from_user(&buf, sizeof(buf), ptr);
if (len == -2 && ret == 0 && buf == 1234)
copy_test++;
if (len == -3 && ret == -EFAULT)
copy_test++;
if (len == -4 && ret == -EFAULT)
copy_test++;
return 0;
}
|