1// SPDX-License-Identifier: GPL-2.0
2#include <linux/bpf.h>
3#include <bpf/bpf_helpers.h>
4#include "bpf_misc.h"
5
6#define __unused __attribute__((unused))
7
8struct {
9	__uint(type, BPF_MAP_TYPE_PROG_ARRAY);
10	__uint(max_entries, 1);
11	__uint(key_size, sizeof(__u32));
12	__uint(value_size, sizeof(__u32));
13} jmp_table SEC(".maps");
14
15int done = 0;
16
17SEC("tc")
18int classifier_0(struct __sk_buff *skb __unused)
19{
20	done = 1;
21	return 0;
22}
23
24static __noinline
25int subprog_tail(struct __sk_buff *skb)
26{
27	/* Don't propagate the constant to the caller */
28	volatile int ret = 1;
29
30	bpf_tail_call_static(skb, &jmp_table, 0);
31	return ret;
32}
33
34SEC("tc")
35int entry(struct __sk_buff *skb)
36{
37	/* Have data on stack which size is not a multiple of 8 */
38	volatile char arr[1] = {};
39
40	__sink(arr[0]);
41
42	return subprog_tail(skb);
43}
44
45char __license[] SEC("license") = "GPL";
46