| // 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"; |