1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/bpf.h>
3 #include <bpf/bpf_helpers.h>
4 #include <bpf/bpf_tracing.h>
5 #include <stdbool.h>
6 #include "bpf_kfuncs.h"
7 #include "bpf_misc.h"
8
9 char _license[] SEC("license") = "GPL";
10
11 extern const void bpf_fentry_test1 __ksym;
12 extern const void bpf_fentry_test2 __ksym;
13 extern const void bpf_fentry_test3 __ksym;
14 extern const void bpf_fentry_test4 __ksym;
15 extern const void bpf_fentry_test5 __ksym;
16 extern const void bpf_fentry_test6 __ksym;
17 extern const void bpf_fentry_test7 __ksym;
18 extern const void bpf_fentry_test8 __ksym;
19
20 int pid = 0;
21
22 __u64 kprobe_session_result[8];
23
24 static int session_check(void *ctx)
25 {
26 unsigned int i;
27 __u64 addr;
28 const void *kfuncs[] = {
29 &bpf_fentry_test1,
30 &bpf_fentry_test2,
31 &bpf_fentry_test3,
32 &bpf_fentry_test4,
33 &bpf_fentry_test5,
34 &bpf_fentry_test6,
35 &bpf_fentry_test7,
36 &bpf_fentry_test8,
37 };
38
39 if (bpf_get_current_pid_tgid() >> 32 != pid)
40 return 1;
41
42 addr = bpf_get_func_ip(ctx);
43
44 for (i = 0; i < ARRAY_SIZE(kfuncs); i++) {
45 if (kfuncs[i] == (void *) addr) {
46 kprobe_session_result[i]++;
47 break;
48 }
49 }
50
51 /*
52 * Force probes for function bpf_fentry_test[5-8] not to
53 * install and execute the return probe
54 */
55 if (((const void *) addr == &bpf_fentry_test5) ||
56 ((const void *) addr == &bpf_fentry_test6) ||
57 ((const void *) addr == &bpf_fentry_test7) ||
58 ((const void *) addr == &bpf_fentry_test8))
59 return 1;
60
61 return 0;
62 }
63
64 /*
65 * No tests in here, just to trigger 'bpf_fentry_test*'
66 * through tracing test_run
67 */
68 SEC("fentry/bpf_modify_return_test")
69 int BPF_PROG(trigger)
70 {
71 return 0;
72 }
73
74 SEC("kprobe.session/bpf_fentry_test*")
75 int test_kprobe(struct pt_regs *ctx)
76 {
77 return session_check(ctx);
78 }
79
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