1 // SPDX-License-Identifier: GPL-2.0-only
2 #define _GNU_SOURCE
3 #include <test_progs.h>
4 
5 struct inst {
6 	struct bpf_object *obj;
7 	struct bpf_link   *link;
8 };
9 
load_prog(char * file,char * name,struct inst * inst)10 static struct bpf_program *load_prog(char *file, char *name, struct inst *inst)
11 {
12 	struct bpf_object *obj;
13 	struct bpf_program *prog;
14 	int err;
15 
16 	obj = bpf_object__open_file(file, NULL);
17 	if (!ASSERT_OK_PTR(obj, "obj_open_file"))
18 		return NULL;
19 
20 	inst->obj = obj;
21 
22 	err = bpf_object__load(obj);
23 	if (!ASSERT_OK(err, "obj_load"))
24 		return NULL;
25 
26 	prog = bpf_object__find_program_by_name(obj, name);
27 	if (!ASSERT_OK_PTR(prog, "obj_find_prog"))
28 		return NULL;
29 
30 	return prog;
31 }
32 
33 /* TODO: use different target function to run in concurrent mode */
serial_test_trampoline_count(void)34 void serial_test_trampoline_count(void)
35 {
36 	char *file = "test_trampoline_count.bpf.o";
37 	char *const progs[] = { "fentry_test", "fmod_ret_test", "fexit_test" };
38 	int bpf_max_tramp_links, err, i, prog_fd;
39 	struct bpf_program *prog;
40 	struct bpf_link *link;
41 	struct inst *inst;
42 	LIBBPF_OPTS(bpf_test_run_opts, opts);
43 
44 	bpf_max_tramp_links = get_bpf_max_tramp_links();
45 	if (!ASSERT_GE(bpf_max_tramp_links, 1, "bpf_max_tramp_links"))
46 		return;
47 	inst = calloc(bpf_max_tramp_links + 1, sizeof(*inst));
48 	if (!ASSERT_OK_PTR(inst, "inst"))
49 		return;
50 
51 	/* attach 'allowed' trampoline programs */
52 	for (i = 0; i < bpf_max_tramp_links; i++) {
53 		prog = load_prog(file, progs[i % ARRAY_SIZE(progs)], &inst[i]);
54 		if (!prog)
55 			goto cleanup;
56 
57 		link = bpf_program__attach(prog);
58 		if (!ASSERT_OK_PTR(link, "attach_prog"))
59 			goto cleanup;
60 
61 		inst[i].link = link;
62 	}
63 
64 	/* and try 1 extra.. */
65 	prog = load_prog(file, "fmod_ret_test", &inst[i]);
66 	if (!prog)
67 		goto cleanup;
68 
69 	/* ..that needs to fail */
70 	link = bpf_program__attach(prog);
71 	if (!ASSERT_ERR_PTR(link, "attach_prog")) {
72 		inst[i].link = link;
73 		goto cleanup;
74 	}
75 
76 	/* with E2BIG error */
77 	if (!ASSERT_EQ(libbpf_get_error(link), -E2BIG, "E2BIG"))
78 		goto cleanup;
79 	if (!ASSERT_EQ(link, NULL, "ptr_is_null"))
80 		goto cleanup;
81 
82 	/* and finally execute the probe */
83 	prog_fd = bpf_program__fd(prog);
84 	if (!ASSERT_GE(prog_fd, 0, "bpf_program__fd"))
85 		goto cleanup;
86 
87 	err = bpf_prog_test_run_opts(prog_fd, &opts);
88 	if (!ASSERT_OK(err, "bpf_prog_test_run_opts"))
89 		goto cleanup;
90 
91 	ASSERT_EQ(opts.retval & 0xffff, 4, "bpf_modify_return_test.result");
92 	ASSERT_EQ(opts.retval >> 16, 1, "bpf_modify_return_test.side_effect");
93 
94 cleanup:
95 	for (; i >= 0; i--) {
96 		bpf_link__destroy(inst[i].link);
97 		bpf_object__close(inst[i].obj);
98 	}
99 	free(inst);
100 }
101