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1// SPDX-License-Identifier: GPL-2.02/* Copyright (C) 2024. Huawei Technologies Co., Ltd */3#include "vmlinux.h"4#include <linux/types.h>5#include <bpf/bpf_helpers.h>6 7#include "bpf_misc.h"8 9int target_pid = 0;10void *user_ptr = 0;11int read_ret[9];12 13char _license[] SEC("license") = "GPL";14 15/*16 * This is the only kfunc, the others are helpers17 */18int bpf_copy_from_user_str(void *dst, u32, const void *, u64) __weak __ksym;19 20SEC("fentry/" SYS_PREFIX "sys_nanosleep")21int do_probe_read(void *ctx)22{23 char buf[8];24 25 if ((bpf_get_current_pid_tgid() >> 32) != target_pid)26 return 0;27 28 read_ret[0] = bpf_probe_read_kernel(buf, sizeof(buf), user_ptr);29 read_ret[1] = bpf_probe_read_kernel_str(buf, sizeof(buf), user_ptr);30 read_ret[2] = bpf_probe_read(buf, sizeof(buf), user_ptr);31 read_ret[3] = bpf_probe_read_str(buf, sizeof(buf), user_ptr);32 read_ret[4] = bpf_probe_read_user(buf, sizeof(buf), user_ptr);33 read_ret[5] = bpf_probe_read_user_str(buf, sizeof(buf), user_ptr);34 35 return 0;36}37 38SEC("fentry.s/" SYS_PREFIX "sys_nanosleep")39int do_copy_from_user(void *ctx)40{41 char buf[8];42 43 if ((bpf_get_current_pid_tgid() >> 32) != target_pid)44 return 0;45 46 read_ret[6] = bpf_copy_from_user(buf, sizeof(buf), user_ptr);47 read_ret[7] = bpf_copy_from_user_task(buf, sizeof(buf), user_ptr,48 bpf_get_current_task_btf(), 0);49 read_ret[8] = bpf_copy_from_user_str((char *)buf, sizeof(buf), user_ptr, 0);50 51 return 0;52}53