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 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 effective progs and attach flags in root cg */ 75 err = bpf_prog_query(cgs[0].fd, BPF_CGROUP_INET_EGRESS, 76 BPF_F_QUERY_EFFECTIVE, &attach_flags, NULL, 77 &prog_cnt); 78 CHECK_FAIL(err); 79 CHECK_FAIL(attach_flags != BPF_F_ALLOW_MULTI); 80 if (CHECK(prog_cnt != 1, "effect_cnt", "exp %d, got %d\n", 1, prog_cnt)) 81 goto cleanup; 82 83 /* query the number of effective progs in last cg */ 84 err = bpf_prog_query(cgs[last_cg].fd, BPF_CGROUP_INET_EGRESS, 85 BPF_F_QUERY_EFFECTIVE, NULL, NULL, 86 &prog_cnt); 87 CHECK_FAIL(err); 88 CHECK_FAIL(attach_flags != BPF_F_ALLOW_MULTI); 89 if (CHECK(prog_cnt != cg_nr, "effect_cnt", "exp %d, got %d\n", 90 cg_nr, prog_cnt)) 91 goto cleanup; 92 93 /* query the effective prog IDs in last cg */ 94 err = bpf_prog_query(cgs[last_cg].fd, BPF_CGROUP_INET_EGRESS, 95 BPF_F_QUERY_EFFECTIVE, &attach_flags, 96 prog_ids, &prog_cnt); 97 CHECK_FAIL(err); 98 CHECK_FAIL(attach_flags != BPF_F_ALLOW_MULTI); 99 if (CHECK(prog_cnt != cg_nr, "effect_cnt", "exp %d, got %d\n", 100 cg_nr, prog_cnt)) 101 goto cleanup; 102 for (i = 1; i < prog_cnt; i++) { 103 CHECK(prog_ids[i - 1] != prog_ids[i], "prog_id_check", 104 "idx %d, prev id %d, cur id %d\n", 105 i, prog_ids[i - 1], prog_ids[i]); 106 } 107 108 /* detach bottom program and ping again */ 109 bpf_link__destroy(links[last_cg]); 110 links[last_cg] = NULL; 111 112 ping_and_check(cg_nr - 1, 0); 113 114 /* mix in with non link-based multi-attachments */ 115 err = bpf_prog_attach(prog_fd, cgs[last_cg].fd, 116 BPF_CGROUP_INET_EGRESS, BPF_F_ALLOW_MULTI); 117 if (CHECK(err, "cg_attach_legacy", "errno=%d\n", errno)) 118 goto cleanup; 119 detach_legacy = true; 120 121 links[last_cg] = bpf_program__attach_cgroup(skel->progs.egress, 122 cgs[last_cg].fd); 123 if (!ASSERT_OK_PTR(links[last_cg], "cg_attach")) 124 goto cleanup; 125 126 ping_and_check(cg_nr + 1, 0); 127 128 /* detach link */ 129 bpf_link__destroy(links[last_cg]); 130 links[last_cg] = NULL; 131 132 /* detach legacy */ 133 err = bpf_prog_detach2(prog_fd, cgs[last_cg].fd, BPF_CGROUP_INET_EGRESS); 134 if (CHECK(err, "cg_detach_legacy", "errno=%d\n", errno)) 135 goto cleanup; 136 detach_legacy = false; 137 138 /* attach legacy exclusive prog attachment */ 139 err = bpf_prog_attach(prog_fd, cgs[last_cg].fd, 140 BPF_CGROUP_INET_EGRESS, 0); 141 if (CHECK(err, "cg_attach_exclusive", "errno=%d\n", errno)) 142 goto cleanup; 143 detach_legacy = true; 144 145 /* attempt to mix in with multi-attach bpf_link */ 146 tmp_link = bpf_program__attach_cgroup(skel->progs.egress, 147 cgs[last_cg].fd); 148 if (!ASSERT_ERR_PTR(tmp_link, "cg_attach_fail")) { 149 bpf_link__destroy(tmp_link); 150 goto cleanup; 151 } 152 153 ping_and_check(cg_nr, 0); 154 155 /* detach */ 156 err = bpf_prog_detach2(prog_fd, cgs[last_cg].fd, BPF_CGROUP_INET_EGRESS); 157 if (CHECK(err, "cg_detach_legacy", "errno=%d\n", errno)) 158 goto cleanup; 159 detach_legacy = false; 160 161 ping_and_check(cg_nr - 1, 0); 162 163 /* attach back link-based one */ 164 links[last_cg] = bpf_program__attach_cgroup(skel->progs.egress, 165 cgs[last_cg].fd); 166 if (!ASSERT_OK_PTR(links[last_cg], "cg_attach")) 167 goto cleanup; 168 169 ping_and_check(cg_nr, 0); 170 171 /* check legacy exclusive prog can't be attached */ 172 err = bpf_prog_attach(prog_fd, cgs[last_cg].fd, 173 BPF_CGROUP_INET_EGRESS, 0); 174 if (CHECK(!err, "cg_attach_exclusive", "unexpected success")) { 175 bpf_prog_detach2(prog_fd, cgs[last_cg].fd, BPF_CGROUP_INET_EGRESS); 176 goto cleanup; 177 } 178 179 /* replace BPF programs inside their links for all but first link */ 180 for (i = 1; i < cg_nr; i++) { 181 err = bpf_link__update_program(links[i], skel->progs.egress_alt); 182 if (CHECK(err, "prog_upd", "link #%d\n", i)) 183 goto cleanup; 184 } 185 186 ping_and_check(1, cg_nr - 1); 187 188 /* Attempt program update with wrong expected BPF program */ 189 link_upd_opts.old_prog_fd = bpf_program__fd(skel->progs.egress_alt); 190 link_upd_opts.flags = BPF_F_REPLACE; 191 err = bpf_link_update(bpf_link__fd(links[0]), 192 bpf_program__fd(skel->progs.egress_alt), 193 &link_upd_opts); 194 if (CHECK(err == 0 || errno != EPERM, "prog_cmpxchg1", 195 "unexpectedly succeeded, err %d, errno %d\n", err, -errno)) 196 goto cleanup; 197 198 /* Compare-exchange single link program from egress to egress_alt */ 199 link_upd_opts.old_prog_fd = bpf_program__fd(skel->progs.egress); 200 link_upd_opts.flags = BPF_F_REPLACE; 201 err = bpf_link_update(bpf_link__fd(links[0]), 202 bpf_program__fd(skel->progs.egress_alt), 203 &link_upd_opts); 204 if (CHECK(err, "prog_cmpxchg2", "errno %d\n", -errno)) 205 goto cleanup; 206 207 /* ping */ 208 ping_and_check(0, cg_nr); 209 210 /* close cgroup FDs before detaching links */ 211 for (i = 0; i < cg_nr; i++) { 212 if (cgs[i].fd > 0) { 213 close(cgs[i].fd); 214 cgs[i].fd = -1; 215 } 216 } 217 218 /* BPF programs should still get called */ 219 ping_and_check(0, cg_nr); 220 221 prog_id = link_info_prog_id(links[0], &info); 222 CHECK(prog_id == 0, "link_info", "failed\n"); 223 CHECK(info.cgroup.cgroup_id == 0, "cgroup_id", "unexpected %llu\n", info.cgroup.cgroup_id); 224 225 err = bpf_link__detach(links[0]); 226 if (CHECK(err, "link_detach", "failed %d\n", err)) 227 goto cleanup; 228 229 /* cgroup_id should be zero in link_info */ 230 prog_id = link_info_prog_id(links[0], &info); 231 CHECK(prog_id == 0, "link_info", "failed\n"); 232 CHECK(info.cgroup.cgroup_id != 0, "cgroup_id", "unexpected %llu\n", info.cgroup.cgroup_id); 233 234 /* First BPF program shouldn't be called anymore */ 235 ping_and_check(0, cg_nr - 1); 236 237 /* leave cgroup and remove them, don't detach programs */ 238 cleanup_cgroup_environment(); 239 240 /* BPF programs should have been auto-detached */ 241 ping_and_check(0, 0); 242 243 cleanup: 244 if (detach_legacy) 245 bpf_prog_detach2(prog_fd, cgs[last_cg].fd, 246 BPF_CGROUP_INET_EGRESS); 247 248 for (i = 0; i < cg_nr; i++) { 249 bpf_link__destroy(links[i]); 250 } 251 test_cgroup_link__destroy(skel); 252 253 for (i = 0; i < cg_nr; i++) { 254 if (cgs[i].fd > 0) 255 close(cgs[i].fd); 256 } 257 cleanup_cgroup_environment(); 258 } 259