xref: /linux/tools/testing/selftests/bpf/progs/task_local_storage_exit_creds.c (revision 164666fa66669d437bdcc8d5f1744a2aee73be41)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2021 Facebook */
3 
4 #include "vmlinux.h"
5 #include <bpf/bpf_helpers.h>
6 #include <bpf/bpf_tracing.h>
7 
8 char _license[] SEC("license") = "GPL";
9 
10 struct {
11 	__uint(type, BPF_MAP_TYPE_TASK_STORAGE);
12 	__uint(map_flags, BPF_F_NO_PREALLOC);
13 	__type(key, int);
14 	__type(value, __u64);
15 } task_storage SEC(".maps");
16 
17 int valid_ptr_count = 0;
18 int null_ptr_count = 0;
19 
20 SEC("fentry/exit_creds")
21 int BPF_PROG(trace_exit_creds, struct task_struct *task)
22 {
23 	__u64 *ptr;
24 
25 	ptr = bpf_task_storage_get(&task_storage, task, 0,
26 				   BPF_LOCAL_STORAGE_GET_F_CREATE);
27 	if (ptr)
28 		__sync_fetch_and_add(&valid_ptr_count, 1);
29 	else
30 		__sync_fetch_and_add(&null_ptr_count, 1);
31 	return 0;
32 }
33