1 // SPDX-License-Identifier: GPL-2.0 2 /* 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 9 int target_pid = 0; 10 void *user_ptr = 0; 11 int read_ret[9]; 12 13 char _license[] SEC("license") = "GPL"; 14 15 /* 16 * This is the only kfunc, the others are helpers 17 */ 18 int bpf_copy_from_user_str(void *dst, u32, const void *, u64) __weak __ksym; 19 20 SEC("fentry/" SYS_PREFIX "sys_nanosleep") 21 int 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 38 SEC("fentry.s/" SYS_PREFIX "sys_nanosleep") 39 int 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