1 // SPDX-License-Identifier: GPL-2.0
2
3 #include <test_progs.h>
4 #include "cgroup_helpers.h"
5 #include "testing_helpers.h"
6 #include "test_cgroup_link.skel.h"
7
8 static __u32 duration = 0;
9 #define PING_CMD "ping -q -c1 -w1 127.0.0.1 > /dev/null"
10
11 static struct test_cgroup_link *skel = NULL;
12
13 int ping_and_check(int exp_calls, int exp_alt_calls)
14 {
15 skel->bss->calls = 0;
16 skel->bss->alt_calls = 0;
17 CHECK_FAIL(system(PING_CMD));
18 if (CHECK(skel->bss->calls != exp_calls, "call_cnt",
19 "exp %d, got %d\n", exp_calls, skel->bss->calls))
20 return -EINVAL;
21 if (CHECK(skel->bss->alt_calls != exp_alt_calls, "alt_call_cnt",
22 "exp %d, got %d\n", exp_alt_calls, skel->bss->alt_calls))
23 return -EINVAL;
24 return 0;
25 }
26
27 void serial_test_cgroup_link(void)
28 {
29 struct {
30 const char *path;
31 int fd;
32 } cgs[] = {
33 { "/cg1" },
34 { "/cg1/cg2" },
35 { "/cg1/cg2/cg3" },
36 { "/cg1/cg2/cg3/cg4" },
37 };
38 int last_cg = ARRAY_SIZE(cgs) - 1, cg_nr = ARRAY_SIZE(cgs);
39 DECLARE_LIBBPF_OPTS(bpf_link_update_opts, link_upd_opts);
40 struct bpf_link *links[ARRAY_SIZE(cgs)] = {}, *tmp_link;
41 __u32 prog_ids[ARRAY_SIZE(cgs)], prog_cnt = 0, attach_flags, prog_id;
42 struct bpf_link_info info;
43 int i = 0, err, prog_fd;
44 bool detach_legacy = false;
45
46 skel = test_cgroup_link__open_and_load();
47 if (CHECK(!skel, "skel_open_load", "failed to open/load skeleton\n"))
48 return;
49 prog_fd = bpf_program__fd(skel->progs.egress);
50
51 err = setup_cgroup_environment();
52 if (CHECK(err, "cg_init", "failed: %d\n", err))
53 goto cleanup;
54
55 for (i = 0; i < cg_nr; i++) {
56 cgs[i].fd = create_and_get_cgroup(cgs[i].path);
57 if (!ASSERT_GE(cgs[i].fd, 0, "cg_create"))
58 goto cleanup;
59 }
60
61 err = join_cgroup(cgs[last_cg].path);
62 if (CHECK(err, "cg_join", "fail: %d\n", err))
63 goto cleanup;
64
65 for (i = 0; i < cg_nr; i++) {
66 links[i] = bpf_program__attach_cgroup(skel->progs.egress,
67 cgs[i].fd);
68 if (!ASSERT_OK_PTR(links[i], "cg_attach"))
69 goto cleanup;
70 }
71
72 ping_and_check(cg_nr, 0);
73
74 /* query the number of attached progs and attach flags in root cg */
75 err = bpf_prog_query(cgs[0].fd, BPF_CGROUP_INET_EGRESS,
76 0, &attach_flags, NULL, &prog_cnt);
77 CHECK_FAIL(err);
78 CHECK_FAIL(attach_flags != BPF_F_ALLOW_MULTI);
79 if (CHECK(prog_cnt != 1, "effect_cnt", "exp %d, got %d\n", 1, prog_cnt))
80 goto cleanup;
81
82 /* query the number of effective progs in last cg */
83 err = bpf_prog_query(cgs[last_cg].fd, BPF_CGROUP_INET_EGRESS,
84 BPF_F_QUERY_EFFECTIVE, NULL, NULL,
85 &prog_cnt);
86 CHECK_FAIL(err);
87 if (CHECK(prog_cnt != cg_nr, "effect_cnt", "exp %d, got %d\n",
88 cg_nr, prog_cnt))
89 goto cleanup;
90
91 /* query the effective prog IDs in last cg */
92 err = bpf_prog_query(cgs[last_cg].fd, BPF_CGROUP_INET_EGRESS,
93 BPF_F_QUERY_EFFECTIVE, NULL, prog_ids,
94 &prog_cnt);
95 CHECK_FAIL(err);
96 if (CHECK(prog_cnt != cg_nr, "effect_cnt", "exp %d, got %d\n",
97 cg_nr, prog_cnt))
98 goto cleanup;
99 for (i = 1; i < prog_cnt; i++) {
100 CHECK(prog_ids[i - 1] != prog_ids[i], "prog_id_check",
101 "idx %d, prev id %d, cur id %d\n",
102 i, prog_ids[i - 1], prog_ids[i]);
103 }
104
105 /* detach bottom program and ping again */
106 bpf_link__destroy(links[last_cg]);
107 links[last_cg] = NULL;
108
109 ping_and_check(cg_nr - 1, 0);
110
111 /* mix in with non link-based multi-attachments */
112 err = bpf_prog_attach(prog_fd, cgs[last_cg].fd,
113 BPF_CGROUP_INET_EGRESS, BPF_F_ALLOW_MULTI);
114 if (CHECK(err, "cg_attach_legacy", "errno=%d\n", errno))
115 goto cleanup;
116 detach_legacy = true;
117
118 links[last_cg] = bpf_program__attach_cgroup(skel->progs.egress,
119 cgs[last_cg].fd);
120 if (!ASSERT_OK_PTR(links[last_cg], "cg_attach"))
121 goto cleanup;
122
123 ping_and_check(cg_nr + 1, 0);
124
125 /* detach link */
126 bpf_link__destroy(links[last_cg]);
127 links[last_cg] = NULL;
128
129 /* detach legacy */
130 err = bpf_prog_detach2(prog_fd, cgs[last_cg].fd, BPF_CGROUP_INET_EGRESS);
131 if (CHECK(err, "cg_detach_legacy", "errno=%d\n", errno))
132 goto cleanup;
133 detach_legacy = false;
134
135 /* attach legacy exclusive prog attachment */
136 err = bpf_prog_attach(prog_fd, cgs[last_cg].fd,
137 BPF_CGROUP_INET_EGRESS, 0);
138 if (CHECK(err, "cg_attach_exclusive", "errno=%d\n", errno))
139 goto cleanup;
140 detach_legacy = true;
141
142 /* attempt to mix in with multi-attach bpf_link */
143 tmp_link = bpf_program__attach_cgroup(skel->progs.egress,
144 cgs[last_cg].fd);
145 if (!ASSERT_ERR_PTR(tmp_link, "cg_attach_fail")) {
146 bpf_link__destroy(tmp_link);
147 goto cleanup;
148 }
149
150 ping_and_check(cg_nr, 0);
151
152 /* detach */
153 err = bpf_prog_detach2(prog_fd, cgs[last_cg].fd, BPF_CGROUP_INET_EGRESS);
154 if (CHECK(err, "cg_detach_legacy", "errno=%d\n", errno))
155 goto cleanup;
156 detach_legacy = false;
157
158 ping_and_check(cg_nr - 1, 0);
159
160 /* attach back link-based one */
161 links[last_cg] = bpf_program__attach_cgroup(skel->progs.egress,
162 cgs[last_cg].fd);
163 if (!ASSERT_OK_PTR(links[last_cg], "cg_attach"))
164 goto cleanup;
165
166 ping_and_check(cg_nr, 0);
167
168 /* check legacy exclusive prog can't be attached */
169 err = bpf_prog_attach(prog_fd, cgs[last_cg].fd,
170 BPF_CGROUP_INET_EGRESS, 0);
171 if (CHECK(!err, "cg_attach_exclusive", "unexpected success")) {
172 bpf_prog_detach2(prog_fd, cgs[last_cg].fd, BPF_CGROUP_INET_EGRESS);
173 goto cleanup;
174 }
175
176 /* replace BPF programs inside their links for all but first link */
177 for (i = 1; i < cg_nr; i++) {
178 err = bpf_link__update_program(links[i], skel->progs.egress_alt);
179 if (CHECK(err, "prog_upd", "link #%d\n", i))
180 goto cleanup;
181 }
182
183 ping_and_check(1, cg_nr - 1);
184
185 /* Attempt program update with wrong expected BPF program */
186 link_upd_opts.old_prog_fd = bpf_program__fd(skel->progs.egress_alt);
187 link_upd_opts.flags = BPF_F_REPLACE;
188 err = bpf_link_update(bpf_link__fd(links[0]),
189 bpf_program__fd(skel->progs.egress_alt),
190 &link_upd_opts);
191 if (CHECK(err == 0 || errno != EPERM, "prog_cmpxchg1",
192 "unexpectedly succeeded, err %d, errno %d\n", err, -errno))
193 goto cleanup;
194
195 /* Compare-exchange single link program from egress to egress_alt */
196 link_upd_opts.old_prog_fd = bpf_program__fd(skel->progs.egress);
197 link_upd_opts.flags = BPF_F_REPLACE;
198 err = bpf_link_update(bpf_link__fd(links[0]),
199 bpf_program__fd(skel->progs.egress_alt),
200 &link_upd_opts);
201 if (CHECK(err, "prog_cmpxchg2", "errno %d\n", -errno))
202 goto cleanup;
203
204 /* ping */
205 ping_and_check(0, cg_nr);
206
207 /* close cgroup FDs before detaching links */
208 for (i = 0; i < cg_nr; i++) {
209 if (cgs[i].fd > 0) {
210 close(cgs[i].fd);
211 cgs[i].fd = -1;
212 }
213 }
214
215 /* BPF programs should still get called */
216 ping_and_check(0, cg_nr);
217
218 prog_id = link_info_prog_id(links[0], &info);
219 CHECK(prog_id == 0, "link_info", "failed\n");
220 CHECK(info.cgroup.cgroup_id == 0, "cgroup_id", "unexpected %llu\n", info.cgroup.cgroup_id);
221
222 err = bpf_link__detach(links[0]);
223 if (CHECK(err, "link_detach", "failed %d\n", err))
224 goto cleanup;
225
226 /* cgroup_id should be zero in link_info */
227 prog_id = link_info_prog_id(links[0], &info);
228 CHECK(prog_id == 0, "link_info", "failed\n");
229 CHECK(info.cgroup.cgroup_id != 0, "cgroup_id", "unexpected %llu\n", info.cgroup.cgroup_id);
230
231 /* First BPF program shouldn't be called anymore */
232 ping_and_check(0, cg_nr - 1);
233
234 /* leave cgroup and remove them, don't detach programs */
235 cleanup_cgroup_environment();
236
237 /* BPF programs should have been auto-detached */
238 ping_and_check(0, 0);
239
240 cleanup:
241 if (detach_legacy)
242 bpf_prog_detach2(prog_fd, cgs[last_cg].fd,
243 BPF_CGROUP_INET_EGRESS);
244
245 for (i = 0; i < cg_nr; i++) {
246 bpf_link__destroy(links[i]);
247 }
248 test_cgroup_link__destroy(skel);
249
250 for (i = 0; i < cg_nr; i++) {
251 if (cgs[i].fd > 0)
252 close(cgs[i].fd);
253 }
254 cleanup_cgroup_environment();
255 }
256
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