1// SPDX-License-Identifier: GPL-2.0
2// Copyright (c) 2019 Facebook
3
4#include <linux/bpf.h>
5#include <stdint.h>
6#include <bpf/bpf_helpers.h>
7#include <bpf/bpf_core_read.h>
8
9char _license[] SEC("license") = "GPL";
10
11struct {
12 char in[256];
13 char out[256];
14} data = {};
15
16struct core_reloc_nesting_substruct {
17 int a;
18};
19
20union core_reloc_nesting_subunion {
21 int b;
22};
23
24/* int a.a.a and b.b.b accesses */
25struct core_reloc_nesting {
26 union {
27 struct core_reloc_nesting_substruct a;
28 } a;
29 struct {
30 union core_reloc_nesting_subunion b;
31 } b;
32};
33
34#define CORE_READ(dst, src) bpf_core_read(dst, sizeof(*(dst)), src)
35
36SEC("raw_tracepoint/sys_enter")
37int test_core_nesting(void *ctx)
38{
39 struct core_reloc_nesting *in = (void *)&data.in;
40 struct core_reloc_nesting *out = (void *)&data.out;
41
42 if (CORE_READ(&out->a.a.a, &in->a.a.a))
43 return 1;
44 if (CORE_READ(&out->b.b.b, &in->b.b.b))
45 return 1;
46
47 return 0;
48}
49
50

source code of linux/tools/testing/selftests/bpf/progs/test_core_reloc_nesting.c