xref: /linux/tools/testing/selftests/bpf/progs/trace_printk.c (revision 0fc8f6200d2313278fbf4539bbab74677c685531)
1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (c) 2020, Oracle and/or its affiliates.
3 
4 #include "vmlinux.h"
5 #include <bpf/bpf_helpers.h>
6 #include <bpf/bpf_tracing.h>
7 #include "bpf_misc.h"
8 
9 char _license[] SEC("license") = "GPL";
10 
11 int trace_printk_ret = 0;
12 int trace_printk_ran = 0;
13 int trace_printk_invalid_spec_ret = 0;
14 int trace_printk_utf8_ret = 0;
15 int trace_printk_utf8_ran = 0;
16 
17 const char fmt[] = "Testing,testing %d\n";
18 static const char utf8_fmt[] = "中文,测试 %d\n";
19 /* Non-ASCII bytes after '%' must still be rejected. */
20 static const char invalid_spec_fmt[] = "%\x80\n";
21 
22 SEC("fentry/" SYS_PREFIX "sys_nanosleep")
23 int sys_enter(void *ctx)
24 {
25 	trace_printk_ret = bpf_trace_printk(fmt, sizeof(fmt),
26 					    ++trace_printk_ran);
27 	trace_printk_utf8_ret = bpf_trace_printk(utf8_fmt, sizeof(utf8_fmt),
28 						 ++trace_printk_utf8_ran);
29 	trace_printk_invalid_spec_ret = bpf_trace_printk(invalid_spec_fmt,
30 							 sizeof(invalid_spec_fmt));
31 	return 0;
32 }
33