1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
|
// SPDX-License-Identifier: GPL-2.0-only
#define _GNU_SOURCE
#include <sched.h>
#include <sys/prctl.h>
#include <test_progs.h>
#define MAX_TRAMP_PROGS 38
struct inst {
struct bpf_object *obj;
struct bpf_link *link_fentry;
struct bpf_link *link_fexit;
};
static int test_task_rename(void)
{
int fd, duration = 0, err;
char buf[] = "test_overhead";
fd = open("/proc/self/comm", O_WRONLY|O_TRUNC);
if (CHECK(fd < 0, "open /proc", "err %d", errno))
return -1;
err = write(fd, buf, sizeof(buf));
if (err < 0) {
CHECK(err < 0, "task rename", "err %d", errno);
close(fd);
return -1;
}
close(fd);
return 0;
}
static struct bpf_link *load(struct bpf_object *obj, const char *name)
{
struct bpf_program *prog;
int duration = 0;
prog = bpf_object__find_program_by_name(obj, name);
if (CHECK(!prog, "find_probe", "prog '%s' not found\n", name))
return ERR_PTR(-EINVAL);
return bpf_program__attach_trace(prog);
}
/* TODO: use different target function to run in concurrent mode */
void serial_test_trampoline_count(void)
{
const char *fentry_name = "prog1";
const char *fexit_name = "prog2";
const char *object = "test_trampoline_count.o";
struct inst inst[MAX_TRAMP_PROGS] = {};
int err, i = 0, duration = 0;
struct bpf_object *obj;
struct bpf_link *link;
char comm[16] = {};
/* attach 'allowed' trampoline programs */
for (i = 0; i < MAX_TRAMP_PROGS; i++) {
obj = bpf_object__open_file(object, NULL);
if (!ASSERT_OK_PTR(obj, "obj_open_file")) {
obj = NULL;
goto cleanup;
}
err = bpf_object__load(obj);
if (CHECK(err, "obj_load", "err %d\n", err))
goto cleanup;
inst[i].obj = obj;
obj = NULL;
if (rand() % 2) {
link = load(inst[i].obj, fentry_name);
if (!ASSERT_OK_PTR(link, "attach_prog")) {
link = NULL;
goto cleanup;
}
inst[i].link_fentry = link;
} else {
link = load(inst[i].obj, fexit_name);
if (!ASSERT_OK_PTR(link, "attach_prog")) {
link = NULL;
goto cleanup;
}
inst[i].link_fexit = link;
}
}
/* and try 1 extra.. */
obj = bpf_object__open_file(object, NULL);
if (!ASSERT_OK_PTR(obj, "obj_open_file")) {
obj = NULL;
goto cleanup;
}
err = bpf_object__load(obj);
if (CHECK(err, "obj_load", "err %d\n", err))
goto cleanup_extra;
/* ..that needs to fail */
link = load(obj, fentry_name);
err = libbpf_get_error(link);
if (!ASSERT_ERR_PTR(link, "cannot attach over the limit")) {
bpf_link__destroy(link);
goto cleanup_extra;
}
/* with E2BIG error */
ASSERT_EQ(err, -E2BIG, "proper error check");
ASSERT_EQ(link, NULL, "ptr_is_null");
/* and finaly execute the probe */
if (CHECK_FAIL(prctl(PR_GET_NAME, comm, 0L, 0L, 0L)))
goto cleanup_extra;
CHECK_FAIL(test_task_rename());
CHECK_FAIL(prctl(PR_SET_NAME, comm, 0L, 0L, 0L));
cleanup_extra:
bpf_object__close(obj);
cleanup:
if (i >= MAX_TRAMP_PROGS)
i = MAX_TRAMP_PROGS - 1;
for (; i >= 0; i--) {
bpf_link__destroy(inst[i].link_fentry);
bpf_link__destroy(inst[i].link_fexit);
bpf_object__close(inst[i].obj);
}
}
|
