1// SPDX-License-Identifier: GPL-2.0-only
 2
 3#include <sys/socket.h>
 4#include <linux/bpf.h>
 5#include <bpf/bpf_helpers.h>
 6
 7int invocations = 0, in_use = 0;
 8
 9struct {
10	__uint(type, BPF_MAP_TYPE_SK_STORAGE);
11	__uint(map_flags, BPF_F_NO_PREALLOC);
12	__type(key, int);
13	__type(value, int);
14} sk_map SEC(".maps");
15
16SEC("cgroup/sock_create")
17int sock(struct bpf_sock *ctx)
18{
19	int *sk_storage;
20
21	if (ctx->type != SOCK_DGRAM)
22		return 1;
23
24	sk_storage = bpf_sk_storage_get(&sk_map, ctx, 0,
25					BPF_SK_STORAGE_GET_F_CREATE);
26	if (!sk_storage)
27		return 0;
28	*sk_storage = 0xdeadbeef;
29
30	__sync_fetch_and_add(&invocations, 1);
31
32	if (in_use > 0) {
33		/* BPF_CGROUP_INET_SOCK_RELEASE is _not_ called
34		 * when we return an error from the BPF
35		 * program!
36		 */
37		return 0;
38	}
39
40	__sync_fetch_and_add(&in_use, 1);
41	return 1;
42}
43
44SEC("cgroup/sock_release")
45int sock_release(struct bpf_sock *ctx)
46{
47	int *sk_storage;
48
49	if (ctx->type != SOCK_DGRAM)
50		return 1;
51
52	sk_storage = bpf_sk_storage_get(&sk_map, ctx, 0, 0);
53	if (!sk_storage || *sk_storage != 0xdeadbeef)
54		return 0;
55
56	__sync_fetch_and_add(&invocations, 1);
57	__sync_fetch_and_add(&in_use, -1);
58	return 1;
59}

 1// SPDX-License-Identifier: GPL-2.0-only
 2
 3#include <sys/socket.h>
 4#include <linux/bpf.h>
 5#include <bpf/bpf_helpers.h>
 6
 7int invocations = 0, in_use = 0;
 8
 9struct {
10	__uint(type, BPF_MAP_TYPE_SK_STORAGE);
11	__uint(map_flags, BPF_F_NO_PREALLOC);
12	__type(key, int);
13	__type(value, int);
14} sk_map SEC(".maps");
15
16SEC("cgroup/sock_create")
17int sock(struct bpf_sock *ctx)
18{
19	int *sk_storage;
20
21	if (ctx->type != SOCK_DGRAM)
22		return 1;
23
24	sk_storage = bpf_sk_storage_get(&sk_map, ctx, 0,
25					BPF_SK_STORAGE_GET_F_CREATE);
26	if (!sk_storage)
27		return 0;
28	*sk_storage = 0xdeadbeef;
29
30	__sync_fetch_and_add(&invocations, 1);
31
32	if (in_use > 0) {
33		/* BPF_CGROUP_INET_SOCK_RELEASE is _not_ called
34		 * when we return an error from the BPF
35		 * program!
36		 */
37		return 0;
38	}
39
40	__sync_fetch_and_add(&in_use, 1);
41	return 1;
42}
43
44SEC("cgroup/sock_release")
45int sock_release(struct bpf_sock *ctx)
46{
47	int *sk_storage;
48
49	if (ctx->type != SOCK_DGRAM)
50		return 1;
51
52	sk_storage = bpf_sk_storage_get(&sk_map, ctx, 0, 0);
53	if (!sk_storage || *sk_storage != 0xdeadbeef)
54		return 0;
55
56	__sync_fetch_and_add(&invocations, 1);
57	__sync_fetch_and_add(&in_use, -1);
58	return 1;
59}