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1// SPDX-License-Identifier: GPL-2.02/* Copyright (c) 2021 Facebook */3 4#include "vmlinux.h"5#include <bpf/bpf_helpers.h>6#include <bpf/bpf_tracing.h>7 8char _license[] SEC("license") = "GPL";9 10struct {11 __uint(type, BPF_MAP_TYPE_TASK_STORAGE);12 __uint(map_flags, BPF_F_NO_PREALLOC);13 __type(key, int);14 __type(value, long);15} enter_id SEC(".maps");16 17#define MAGIC_VALUE 0xabcd123418 19pid_t target_pid = 0;20int mismatch_cnt = 0;21int enter_cnt = 0;22int exit_cnt = 0;23 24SEC("tp_btf/sys_enter")25int BPF_PROG(on_enter, struct pt_regs *regs, long id)26{27 struct task_struct *task;28 long *ptr;29 30 task = bpf_get_current_task_btf();31 if (task->pid != target_pid)32 return 0;33 34 ptr = bpf_task_storage_get(&enter_id, task, 0,35 BPF_LOCAL_STORAGE_GET_F_CREATE);36 if (!ptr)37 return 0;38 39 __sync_fetch_and_add(&enter_cnt, 1);40 *ptr = MAGIC_VALUE + enter_cnt;41 42 return 0;43}44 45SEC("tp_btf/sys_exit")46int BPF_PROG(on_exit, struct pt_regs *regs, long id)47{48 struct task_struct *task;49 long *ptr;50 51 task = bpf_get_current_task_btf();52 if (task->pid != target_pid)53 return 0;54 55 ptr = bpf_task_storage_get(&enter_id, task, 0,56 BPF_LOCAL_STORAGE_GET_F_CREATE);57 if (!ptr)58 return 0;59 60 __sync_fetch_and_add(&exit_cnt, 1);61 if (*ptr != MAGIC_VALUE + exit_cnt)62 __sync_fetch_and_add(&mismatch_cnt, 1);63 return 0;64}65