map_excl.c

 1// SPDX-License-Identifier: GPL-2.0
 2/* Copyright (C) 2025 Google LLC. */
 3#include <linux/bpf.h>
 4#include <time.h>
 5#include <bpf/bpf_helpers.h>
 6
 7#include "bpf_misc.h"
 8
 9struct {
10	__uint(type, BPF_MAP_TYPE_ARRAY);
11	__type(key, __u32);
12	__type(value, __u32);
13	__uint(max_entries, 1);
14} excl_map SEC(".maps");
15
16char _license[] SEC("license") = "GPL";
17
18SEC("?fentry.s/" SYS_PREFIX "sys_getpgid")
19int should_have_access(void *ctx)
20{
21	int key = 0, value = 0xdeadbeef;
22
23	bpf_map_update_elem(&excl_map, &key, &value, 0);
24	return 0;
25}
26
27SEC("?fentry.s/" SYS_PREFIX "sys_getpgid")
28int should_not_have_access(void *ctx)
29{
30	int key = 0, value = 0xdeadbeef;
31
32	bpf_map_update_elem(&excl_map, &key, &value, 0);
33	return 0;
34}