41 lines
768 B
C
41 lines
768 B
C
// SPDX-License-Identifier: GPL-2.0
|
|
// Copyright (c) 2020 Facebook
|
|
|
|
#include <linux/ptrace.h>
|
|
#include <linux/bpf.h>
|
|
#include <bpf/bpf_helpers.h>
|
|
#include <bpf/bpf_tracing.h>
|
|
|
|
#define VAR_NUM 2
|
|
|
|
struct hmap_elem {
|
|
struct bpf_spin_lock lock;
|
|
int var[VAR_NUM];
|
|
};
|
|
|
|
struct {
|
|
__uint(type, BPF_MAP_TYPE_HASH);
|
|
__uint(max_entries, 1);
|
|
__type(key, __u32);
|
|
__type(value, struct hmap_elem);
|
|
} hash_map SEC(".maps");
|
|
|
|
SEC("freplace/handle_kprobe")
|
|
int new_handle_kprobe(struct pt_regs *ctx)
|
|
{
|
|
struct hmap_elem zero = {}, *val;
|
|
int key = 0;
|
|
|
|
val = bpf_map_lookup_elem(&hash_map, &key);
|
|
if (!val)
|
|
return 1;
|
|
/* spin_lock in hash map */
|
|
bpf_spin_lock(&val->lock);
|
|
val->var[0] = 99;
|
|
bpf_spin_unlock(&val->lock);
|
|
|
|
return 0;
|
|
}
|
|
|
|
char _license[] SEC("license") = "GPL";
|