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