// SPDX-License-Identifier: GPL-2.0 #include #include "cgroup_helpers.h" #define PING_CMD "ping -q -c1 -w1 127.0.0.1 > /dev/null" static char bpf_log_buf[BPF_LOG_BUF_SIZE]; static int map_fd = -1; static int prog_load_cnt(int verdict, int val) { int cgroup_storage_fd, percpu_cgroup_storage_fd; if (map_fd < 0) map_fd = bpf_create_map(BPF_MAP_TYPE_ARRAY, 4, 8, 1, 0); if (map_fd < 0) { printf("failed to create map '%s'\n", strerror(errno)); return -1; } cgroup_storage_fd = bpf_create_map(BPF_MAP_TYPE_CGROUP_STORAGE, sizeof(struct bpf_cgroup_storage_key), 8, 0, 0); if (cgroup_storage_fd < 0) { printf("failed to create map '%s'\n", strerror(errno)); return -1; } percpu_cgroup_storage_fd = bpf_create_map( BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE, sizeof(struct bpf_cgroup_storage_key), 8, 0, 0); if (percpu_cgroup_storage_fd < 0) { printf("failed to create map '%s'\n", strerror(errno)); return -1; } struct bpf_insn prog[] = { BPF_MOV32_IMM(BPF_REG_0, 0), BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_0, -4), /* *(u32 *)(fp - 4) = r0 */ BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -4), /* r2 = fp - 4 */ BPF_LD_MAP_FD(BPF_REG_1, map_fd), BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem), BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2), BPF_MOV64_IMM(BPF_REG_1, val), /* r1 = 1 */ BPF_ATOMIC_OP(BPF_DW, BPF_ADD, BPF_REG_0, BPF_REG_1, 0), BPF_LD_MAP_FD(BPF_REG_1, cgroup_storage_fd), BPF_MOV64_IMM(BPF_REG_2, 0), BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_get_local_storage), BPF_MOV64_IMM(BPF_REG_1, val), BPF_ATOMIC_OP(BPF_W, BPF_ADD, BPF_REG_0, BPF_REG_1, 0), BPF_LD_MAP_FD(BPF_REG_1, percpu_cgroup_storage_fd), BPF_MOV64_IMM(BPF_REG_2, 0), BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_get_local_storage), BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_0, 0), BPF_ALU64_IMM(BPF_ADD, BPF_REG_3, 0x1), BPF_STX_MEM(BPF_W, BPF_REG_0, BPF_REG_3, 0), BPF_MOV64_IMM(BPF_REG_0, verdict), /* r0 = verdict */ BPF_EXIT_INSN(), }; size_t insns_cnt = sizeof(prog) / sizeof(struct bpf_insn); int ret; ret = bpf_load_program(BPF_PROG_TYPE_CGROUP_SKB, prog, insns_cnt, "GPL", 0, bpf_log_buf, BPF_LOG_BUF_SIZE); close(cgroup_storage_fd); return ret; } void serial_test_cgroup_attach_multi(void) { __u32 prog_ids[4], prog_cnt = 0, attach_flags, saved_prog_id; int cg1 = 0, cg2 = 0, cg3 = 0, cg4 = 0, cg5 = 0, key = 0; DECLARE_LIBBPF_OPTS(bpf_prog_attach_opts, attach_opts); int allow_prog[7] = {-1}; unsigned long long value; __u32 duration = 0; int i = 0; for (i = 0; i < ARRAY_SIZE(allow_prog); i++) { allow_prog[i] = prog_load_cnt(1, 1 << i); if (CHECK(allow_prog[i] < 0, "prog_load", "verifier output:\n%s\n-------\n", bpf_log_buf)) goto err; } if (CHECK_FAIL(setup_cgroup_environment())) goto err; cg1 = create_and_get_cgroup("/cg1"); if (CHECK_FAIL(cg1 < 0)) goto err; cg2 = create_and_get_cgroup("/cg1/cg2"); if (CHECK_FAIL(cg2 < 0)) goto err; cg3 = create_and_get_cgroup("/cg1/cg2/cg3"); if (CHECK_FAIL(cg3 < 0)) goto err; cg4 = create_and_get_cgroup("/cg1/cg2/cg3/cg4"); if (CHECK_FAIL(cg4 < 0)) goto err; cg5 = create_and_get_cgroup("/cg1/cg2/cg3/cg4/cg5"); if (CHECK_FAIL(cg5 < 0)) goto err; if (CHECK_FAIL(join_cgroup("/cg1/cg2/cg3/cg4/cg5"))) goto err; if (CHECK(bpf_prog_attach(allow_prog[0], cg1, BPF_CGROUP_INET_EGRESS, BPF_F_ALLOW_MULTI), "prog0_attach_to_cg1_multi", "errno=%d\n", errno)) goto err; if (CHECK(!bpf_prog_attach(allow_prog[0], cg1, BPF_CGROUP_INET_EGRESS, BPF_F_ALLOW_MULTI), "fail_same_prog_attach_to_cg1", "unexpected success\n")) goto err; if (CHECK(bpf_prog_attach(allow_prog[1], cg1, BPF_CGROUP_INET_EGRESS, BPF_F_ALLOW_MULTI), "prog1_attach_to_cg1_multi", "errno=%d\n", errno)) goto err; if (CHECK(bpf_prog_attach(allow_prog[2], cg2, BPF_CGROUP_INET_EGRESS, BPF_F_ALLOW_OVERRIDE), "prog2_attach_to_cg2_override", "errno=%d\n", errno)) goto err; if (CHECK(bpf_prog_attach(allow_prog[3], cg3, BPF_CGROUP_INET_EGRESS, BPF_F_ALLOW_MULTI), "prog3_attach_to_cg3_multi", "errno=%d\n", errno)) goto err; if (CHECK(bpf_prog_attach(allow_prog[4], cg4, BPF_CGROUP_INET_EGRESS, BPF_F_ALLOW_OVERRIDE), "prog4_attach_to_cg4_override", "errno=%d\n", errno)) goto err; if (CHECK(bpf_prog_attach(allow_prog[5], cg5, BPF_CGROUP_INET_EGRESS, 0), "prog5_attach_to_cg5_none", "errno=%d\n", errno)) goto err; CHECK_FAIL(system(PING_CMD)); CHECK_FAIL(bpf_map_lookup_elem(map_fd, &key, &value)); CHECK_FAIL(value != 1 + 2 + 8 + 32); /* query the number of effective progs in cg5 */ CHECK_FAIL(bpf_prog_query(cg5, BPF_CGROUP_INET_EGRESS, BPF_F_QUERY_EFFECTIVE, NULL, NULL, &prog_cnt)); CHECK_FAIL(prog_cnt != 4); /* retrieve prog_ids of effective progs in cg5 */ CHECK_FAIL(bpf_prog_query(cg5, BPF_CGROUP_INET_EGRESS, BPF_F_QUERY_EFFECTIVE, &attach_flags, prog_ids, &prog_cnt)); CHECK_FAIL(prog_cnt != 4); CHECK_FAIL(attach_flags != 0); saved_prog_id = prog_ids[0]; /* check enospc handling */ prog_ids[0] = 0; prog_cnt = 2; CHECK_FAIL(bpf_prog_query(cg5, BPF_CGROUP_INET_EGRESS, BPF_F_QUERY_EFFECTIVE, &attach_flags, prog_ids, &prog_cnt) >= 0); CHECK_FAIL(errno != ENOSPC); CHECK_FAIL(prog_cnt != 4); /* check that prog_ids are returned even when buffer is too small */ CHECK_FAIL(prog_ids[0] != saved_prog_id); /* retrieve prog_id of single attached prog in cg5 */ prog_ids[0] = 0; CHECK_FAIL(bpf_prog_query(cg5, BPF_CGROUP_INET_EGRESS, 0, NULL, prog_ids, &prog_cnt)); CHECK_FAIL(prog_cnt != 1); CHECK_FAIL(prog_ids[0] != saved_prog_id); /* detach bottom program and ping again */ if (CHECK(bpf_prog_detach2(-1, cg5, BPF_CGROUP_INET_EGRESS), "prog_detach_from_cg5", "errno=%d\n", errno)) goto err; value = 0; CHECK_FAIL(bpf_map_update_elem(map_fd, &key, &value, 0)); CHECK_FAIL(system(PING_CMD)); CHECK_FAIL(bpf_map_lookup_elem(map_fd, &key, &value)); CHECK_FAIL(value != 1 + 2 + 8 + 16); /* test replace */ attach_opts.flags = BPF_F_ALLOW_OVERRIDE | BPF_F_REPLACE; attach_opts.replace_prog_fd = allow_prog[0]; if (CHECK(!bpf_prog_attach_xattr(allow_prog[6], cg1, BPF_CGROUP_INET_EGRESS, &attach_opts), "fail_prog_replace_override", "unexpected success\n")) goto err; CHECK_FAIL(errno != EINVAL); attach_opts.flags = BPF_F_REPLACE; if (CHECK(!bpf_prog_attach_xattr(allow_prog[6], cg1, BPF_CGROUP_INET_EGRESS, &attach_opts), "fail_prog_replace_no_multi", "unexpected success\n")) goto err; CHECK_FAIL(errno != EINVAL); attach_opts.flags = BPF_F_ALLOW_MULTI | BPF_F_REPLACE; attach_opts.replace_prog_fd = -1; if (CHECK(!bpf_prog_attach_xattr(allow_prog[6], cg1, BPF_CGROUP_INET_EGRESS, &attach_opts), "fail_prog_replace_bad_fd", "unexpected success\n")) goto err; CHECK_FAIL(errno != EBADF); /* replacing a program that is not attached to cgroup should fail */ attach_opts.replace_prog_fd = allow_prog[3]; if (CHECK(!bpf_prog_attach_xattr(allow_prog[6], cg1, BPF_CGROUP_INET_EGRESS, &attach_opts), "fail_prog_replace_no_ent", "unexpected success\n")) goto err; CHECK_FAIL(errno != ENOENT); /* replace 1st from the top program */ attach_opts.replace_prog_fd = allow_prog[0]; if (CHECK(bpf_prog_attach_xattr(allow_prog[6], cg1, BPF_CGROUP_INET_EGRESS, &attach_opts), "prog_replace", "errno=%d\n", errno)) goto err; /* replace program with itself */ attach_opts.replace_prog_fd = allow_prog[6]; if (CHECK(bpf_prog_attach_xattr(allow_prog[6], cg1, BPF_CGROUP_INET_EGRESS, &attach_opts), "prog_replace", "errno=%d\n", errno)) goto err; value = 0; CHECK_FAIL(bpf_map_update_elem(map_fd, &key, &value, 0)); CHECK_FAIL(system(PING_CMD)); CHECK_FAIL(bpf_map_lookup_elem(map_fd, &key, &value)); CHECK_FAIL(value != 64 + 2 + 8 + 16); /* detach 3rd from bottom program and ping again */ if (CHECK(!bpf_prog_detach2(0, cg3, BPF_CGROUP_INET_EGRESS), "fail_prog_detach_from_cg3", "unexpected success\n")) goto err; if (CHECK(bpf_prog_detach2(allow_prog[3], cg3, BPF_CGROUP_INET_EGRESS), "prog3_detach_from_cg3", "errno=%d\n", errno)) goto err; value = 0; CHECK_FAIL(bpf_map_update_elem(map_fd, &key, &value, 0)); CHECK_FAIL(system(PING_CMD)); CHECK_FAIL(bpf_map_lookup_elem(map_fd, &key, &value)); CHECK_FAIL(value != 64 + 2 + 16); /* detach 2nd from bottom program and ping again */ if (CHECK(bpf_prog_detach2(-1, cg4, BPF_CGROUP_INET_EGRESS), "prog_detach_from_cg4", "errno=%d\n", errno)) goto err; value = 0; CHECK_FAIL(bpf_map_update_elem(map_fd, &key, &value, 0)); CHECK_FAIL(system(PING_CMD)); CHECK_FAIL(bpf_map_lookup_elem(map_fd, &key, &value)); CHECK_FAIL(value != 64 + 2 + 4); prog_cnt = 4; CHECK_FAIL(bpf_prog_query(cg5, BPF_CGROUP_INET_EGRESS, BPF_F_QUERY_EFFECTIVE, &attach_flags, prog_ids, &prog_cnt)); CHECK_FAIL(prog_cnt != 3); CHECK_FAIL(attach_flags != 0); CHECK_FAIL(bpf_prog_query(cg5, BPF_CGROUP_INET_EGRESS, 0, NULL, prog_ids, &prog_cnt)); CHECK_FAIL(prog_cnt != 0); err: for (i = 0; i < ARRAY_SIZE(allow_prog); i++) if (allow_prog[i] >= 0) close(allow_prog[i]); close(cg1); close(cg2); close(cg3); close(cg4); close(cg5); cleanup_cgroup_environment(); }