blob: ddbe11b46eef86d5d345c5a8152da8e47f8b8627 (
plain)
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
|
// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2024 Meta Platforms, Inc. and affiliates. */
#include <vmlinux.h>
#include <bpf/bpf_helpers.h>
#include "uptr_test_common.h"
struct task_struct *bpf_task_from_pid(s32 pid) __ksym;
void bpf_task_release(struct task_struct *p) __ksym;
void bpf_cgroup_release(struct cgroup *cgrp) __ksym;
struct {
__uint(type, BPF_MAP_TYPE_TASK_STORAGE);
__uint(map_flags, BPF_F_NO_PREALLOC);
__type(key, int);
__type(value, struct value_type);
} datamap SEC(".maps");
pid_t target_pid = 0;
pid_t parent_pid = 0;
SEC("tp_btf/sys_enter")
int on_enter(__u64 *ctx)
{
struct task_struct *task, *data_task;
struct value_type *ptr;
struct user_data *udata;
struct cgroup *cgrp;
task = bpf_get_current_task_btf();
if (task->pid != target_pid)
return 0;
data_task = bpf_task_from_pid(parent_pid);
if (!data_task)
return 0;
ptr = bpf_task_storage_get(&datamap, data_task, 0, 0);
bpf_task_release(data_task);
if (!ptr)
return 0;
cgrp = bpf_kptr_xchg(&ptr->cgrp, NULL);
if (cgrp) {
int lvl = cgrp->level;
bpf_cgroup_release(cgrp);
return lvl;
}
udata = ptr->udata;
if (!udata || udata->result)
return 0;
udata->result = MAGIC_VALUE + udata->a + udata->b;
udata = ptr->nested.udata;
if (udata && !udata->nested_result)
udata->nested_result = udata->result;
return 0;
}
char _license[] SEC("license") = "GPL";
|
