1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun
3*4882a593Smuzhiyun /*
4*4882a593Smuzhiyun * Copyright 2020 Google LLC.
5*4882a593Smuzhiyun */
6*4882a593Smuzhiyun
7*4882a593Smuzhiyun #include "vmlinux.h"
8*4882a593Smuzhiyun #include <bpf/bpf_helpers.h>
9*4882a593Smuzhiyun #include <bpf/bpf_tracing.h>
10*4882a593Smuzhiyun #include <errno.h>
11*4882a593Smuzhiyun
12*4882a593Smuzhiyun struct {
13*4882a593Smuzhiyun __uint(type, BPF_MAP_TYPE_ARRAY);
14*4882a593Smuzhiyun __uint(max_entries, 1);
15*4882a593Smuzhiyun __type(key, __u32);
16*4882a593Smuzhiyun __type(value, __u64);
17*4882a593Smuzhiyun } array SEC(".maps");
18*4882a593Smuzhiyun
19*4882a593Smuzhiyun struct {
20*4882a593Smuzhiyun __uint(type, BPF_MAP_TYPE_HASH);
21*4882a593Smuzhiyun __uint(max_entries, 1);
22*4882a593Smuzhiyun __type(key, __u32);
23*4882a593Smuzhiyun __type(value, __u64);
24*4882a593Smuzhiyun } hash SEC(".maps");
25*4882a593Smuzhiyun
26*4882a593Smuzhiyun struct {
27*4882a593Smuzhiyun __uint(type, BPF_MAP_TYPE_LRU_HASH);
28*4882a593Smuzhiyun __uint(max_entries, 1);
29*4882a593Smuzhiyun __type(key, __u32);
30*4882a593Smuzhiyun __type(value, __u64);
31*4882a593Smuzhiyun } lru_hash SEC(".maps");
32*4882a593Smuzhiyun
33*4882a593Smuzhiyun char _license[] SEC("license") = "GPL";
34*4882a593Smuzhiyun
35*4882a593Smuzhiyun int monitored_pid = 0;
36*4882a593Smuzhiyun int mprotect_count = 0;
37*4882a593Smuzhiyun int bprm_count = 0;
38*4882a593Smuzhiyun
39*4882a593Smuzhiyun SEC("lsm/file_mprotect")
BPF_PROG(test_int_hook,struct vm_area_struct * vma,unsigned long reqprot,unsigned long prot,int ret)40*4882a593Smuzhiyun int BPF_PROG(test_int_hook, struct vm_area_struct *vma,
41*4882a593Smuzhiyun unsigned long reqprot, unsigned long prot, int ret)
42*4882a593Smuzhiyun {
43*4882a593Smuzhiyun if (ret != 0)
44*4882a593Smuzhiyun return ret;
45*4882a593Smuzhiyun
46*4882a593Smuzhiyun __u32 pid = bpf_get_current_pid_tgid() >> 32;
47*4882a593Smuzhiyun int is_stack = 0;
48*4882a593Smuzhiyun
49*4882a593Smuzhiyun is_stack = (vma->vm_start <= vma->vm_mm->start_stack &&
50*4882a593Smuzhiyun vma->vm_end >= vma->vm_mm->start_stack);
51*4882a593Smuzhiyun
52*4882a593Smuzhiyun if (is_stack && monitored_pid == pid) {
53*4882a593Smuzhiyun mprotect_count++;
54*4882a593Smuzhiyun ret = -EPERM;
55*4882a593Smuzhiyun }
56*4882a593Smuzhiyun
57*4882a593Smuzhiyun return ret;
58*4882a593Smuzhiyun }
59*4882a593Smuzhiyun
60*4882a593Smuzhiyun SEC("lsm.s/bprm_committed_creds")
BPF_PROG(test_void_hook,struct linux_binprm * bprm)61*4882a593Smuzhiyun int BPF_PROG(test_void_hook, struct linux_binprm *bprm)
62*4882a593Smuzhiyun {
63*4882a593Smuzhiyun __u32 pid = bpf_get_current_pid_tgid() >> 32;
64*4882a593Smuzhiyun char args[64];
65*4882a593Smuzhiyun __u32 key = 0;
66*4882a593Smuzhiyun __u64 *value;
67*4882a593Smuzhiyun
68*4882a593Smuzhiyun if (monitored_pid == pid)
69*4882a593Smuzhiyun bprm_count++;
70*4882a593Smuzhiyun
71*4882a593Smuzhiyun bpf_copy_from_user(args, sizeof(args), (void *)bprm->vma->vm_mm->arg_start);
72*4882a593Smuzhiyun bpf_copy_from_user(args, sizeof(args), (void *)bprm->mm->arg_start);
73*4882a593Smuzhiyun
74*4882a593Smuzhiyun value = bpf_map_lookup_elem(&array, &key);
75*4882a593Smuzhiyun if (value)
76*4882a593Smuzhiyun *value = 0;
77*4882a593Smuzhiyun value = bpf_map_lookup_elem(&hash, &key);
78*4882a593Smuzhiyun if (value)
79*4882a593Smuzhiyun *value = 0;
80*4882a593Smuzhiyun value = bpf_map_lookup_elem(&lru_hash, &key);
81*4882a593Smuzhiyun if (value)
82*4882a593Smuzhiyun *value = 0;
83*4882a593Smuzhiyun
84*4882a593Smuzhiyun return 0;
85*4882a593Smuzhiyun }
86*4882a593Smuzhiyun SEC("lsm/task_free") /* lsm/ is ok, lsm.s/ fails */
BPF_PROG(test_task_free,struct task_struct * task)87*4882a593Smuzhiyun int BPF_PROG(test_task_free, struct task_struct *task)
88*4882a593Smuzhiyun {
89*4882a593Smuzhiyun return 0;
90*4882a593Smuzhiyun }
91*4882a593Smuzhiyun
92*4882a593Smuzhiyun int copy_test = 0;
93*4882a593Smuzhiyun
94*4882a593Smuzhiyun SEC("fentry.s/__x64_sys_setdomainname")
BPF_PROG(test_sys_setdomainname,struct pt_regs * regs)95*4882a593Smuzhiyun int BPF_PROG(test_sys_setdomainname, struct pt_regs *regs)
96*4882a593Smuzhiyun {
97*4882a593Smuzhiyun void *ptr = (void *)PT_REGS_PARM1(regs);
98*4882a593Smuzhiyun int len = PT_REGS_PARM2(regs);
99*4882a593Smuzhiyun int buf = 0;
100*4882a593Smuzhiyun long ret;
101*4882a593Smuzhiyun
102*4882a593Smuzhiyun ret = bpf_copy_from_user(&buf, sizeof(buf), ptr);
103*4882a593Smuzhiyun if (len == -2 && ret == 0 && buf == 1234)
104*4882a593Smuzhiyun copy_test++;
105*4882a593Smuzhiyun if (len == -3 && ret == -EFAULT)
106*4882a593Smuzhiyun copy_test++;
107*4882a593Smuzhiyun if (len == -4 && ret == -EFAULT)
108*4882a593Smuzhiyun copy_test++;
109*4882a593Smuzhiyun return 0;
110*4882a593Smuzhiyun }
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