xref: /linux/tools/testing/selftests/sched_ext/non_scx_kfunc_deny.c (revision 06bc7ff0a1e0f2b0102e1314e3527a7ec0997851)
1*5897ca15SCheng-Yang Chou /* SPDX-License-Identifier: GPL-2.0 */
2*5897ca15SCheng-Yang Chou /*
3*5897ca15SCheng-Yang Chou  * Verify that context-sensitive SCX kfuncs (even "unlocked" ones) are
4*5897ca15SCheng-Yang Chou  * restricted to only SCX struct_ops programs. Non-SCX struct_ops programs,
5*5897ca15SCheng-Yang Chou  * such as TCP congestion control programs, should be rejected by the BPF
6*5897ca15SCheng-Yang Chou  * verifier when attempting to call these kfuncs.
7*5897ca15SCheng-Yang Chou  *
8*5897ca15SCheng-Yang Chou  * Copyright (C) 2026 Ching-Chun (Jim) Huang <jserv@ccns.ncku.edu.tw>
9*5897ca15SCheng-Yang Chou  * Copyright (C) 2026 Cheng-Yang Chou <yphbchou0911@gmail.com>
10*5897ca15SCheng-Yang Chou  */
11*5897ca15SCheng-Yang Chou 
12*5897ca15SCheng-Yang Chou #include <bpf/bpf.h>
13*5897ca15SCheng-Yang Chou #include <scx/common.h>
14*5897ca15SCheng-Yang Chou #include <unistd.h>
15*5897ca15SCheng-Yang Chou #include <errno.h>
16*5897ca15SCheng-Yang Chou #include <stdio.h>
17*5897ca15SCheng-Yang Chou #include "non_scx_kfunc_deny.bpf.skel.h"
18*5897ca15SCheng-Yang Chou #include "scx_test.h"
19*5897ca15SCheng-Yang Chou 
run(void * ctx)20*5897ca15SCheng-Yang Chou static enum scx_test_status run(void *ctx)
21*5897ca15SCheng-Yang Chou {
22*5897ca15SCheng-Yang Chou 	struct non_scx_kfunc_deny *skel;
23*5897ca15SCheng-Yang Chou 	int err;
24*5897ca15SCheng-Yang Chou 
25*5897ca15SCheng-Yang Chou 	skel = non_scx_kfunc_deny__open();
26*5897ca15SCheng-Yang Chou 	if (!skel) {
27*5897ca15SCheng-Yang Chou 		SCX_ERR("Failed to open skel");
28*5897ca15SCheng-Yang Chou 		return SCX_TEST_FAIL;
29*5897ca15SCheng-Yang Chou 	}
30*5897ca15SCheng-Yang Chou 
31*5897ca15SCheng-Yang Chou 	err = non_scx_kfunc_deny__load(skel);
32*5897ca15SCheng-Yang Chou 	non_scx_kfunc_deny__destroy(skel);
33*5897ca15SCheng-Yang Chou 
34*5897ca15SCheng-Yang Chou 	if (err == 0) {
35*5897ca15SCheng-Yang Chou 		SCX_ERR("non-SCX BPF program loaded when it should have been rejected");
36*5897ca15SCheng-Yang Chou 		return SCX_TEST_FAIL;
37*5897ca15SCheng-Yang Chou 	}
38*5897ca15SCheng-Yang Chou 
39*5897ca15SCheng-Yang Chou 	return SCX_TEST_PASS;
40*5897ca15SCheng-Yang Chou }
41*5897ca15SCheng-Yang Chou 
42*5897ca15SCheng-Yang Chou struct scx_test non_scx_kfunc_deny = {
43*5897ca15SCheng-Yang Chou 	.name = "non_scx_kfunc_deny",
44*5897ca15SCheng-Yang Chou 	.description = "Verify that non-SCX struct_ops programs cannot call SCX kfuncs",
45*5897ca15SCheng-Yang Chou 	.run = run,
46*5897ca15SCheng-Yang Chou };
47*5897ca15SCheng-Yang Chou REGISTER_SCX_TEST(&non_scx_kfunc_deny)
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