xref: /linux/tools/testing/selftests/bpf/progs/read_vsyscall.c (revision eb01fe7abbe2d0b38824d2a93fdb4cc3eaf2ccc1)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (C) 2024. Huawei Technologies Co., Ltd */
3 #include <linux/types.h>
4 #include <bpf/bpf_helpers.h>
5 
6 #include "bpf_misc.h"
7 
8 int target_pid = 0;
9 void *user_ptr = 0;
10 int read_ret[8];
11 
12 char _license[] SEC("license") = "GPL";
13 
14 SEC("fentry/" SYS_PREFIX "sys_nanosleep")
15 int do_probe_read(void *ctx)
16 {
17 	char buf[8];
18 
19 	if ((bpf_get_current_pid_tgid() >> 32) != target_pid)
20 		return 0;
21 
22 	read_ret[0] = bpf_probe_read_kernel(buf, sizeof(buf), user_ptr);
23 	read_ret[1] = bpf_probe_read_kernel_str(buf, sizeof(buf), user_ptr);
24 	read_ret[2] = bpf_probe_read(buf, sizeof(buf), user_ptr);
25 	read_ret[3] = bpf_probe_read_str(buf, sizeof(buf), user_ptr);
26 	read_ret[4] = bpf_probe_read_user(buf, sizeof(buf), user_ptr);
27 	read_ret[5] = bpf_probe_read_user_str(buf, sizeof(buf), user_ptr);
28 
29 	return 0;
30 }
31 
32 SEC("fentry.s/" SYS_PREFIX "sys_nanosleep")
33 int do_copy_from_user(void *ctx)
34 {
35 	char buf[8];
36 
37 	if ((bpf_get_current_pid_tgid() >> 32) != target_pid)
38 		return 0;
39 
40 	read_ret[6] = bpf_copy_from_user(buf, sizeof(buf), user_ptr);
41 	read_ret[7] = bpf_copy_from_user_task(buf, sizeof(buf), user_ptr,
42 					      bpf_get_current_task_btf(), 0);
43 
44 	return 0;
45 }
46