tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0
2#include <vmlinux.h>
3#include <bpf/bpf_helpers.h>
4#include <bpf/bpf_tracing.h>
5#include <stdbool.h>
6#include "bpf_misc.h"
7
8char _license[] SEC("license") = "GPL";
9
10int pid = 0;
11
12int idx_entry = 0;
13int idx_return = 0;
14
15__u64 test_uprobe_cookie_entry[6];
16__u64 test_uprobe_cookie_return[3];
17
18static int check_cookie(struct pt_regs *ctx)
19{
20 __u64 *cookie = bpf_session_cookie(ctx);
21
22 if (bpf_session_is_return(ctx)) {
23 if (idx_return >= ARRAY_SIZE(test_uprobe_cookie_return))
24 return 1;
25 test_uprobe_cookie_return[idx_return++] = *cookie;
26 return 0;
27 }
28
29 if (idx_entry >= ARRAY_SIZE(test_uprobe_cookie_entry))
30 return 1;
31 *cookie = test_uprobe_cookie_entry[idx_entry];
32 return idx_entry++ % 2;
33}
34
35
36SEC("uprobe.session//proc/self/exe:uprobe_session_recursive")
37int uprobe_recursive(struct pt_regs *ctx)
38{
39 if (bpf_get_current_pid_tgid() >> 32 != pid)
40 return 1;
41
42 return check_cookie(ctx);
43}