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