LXR linux/tools/testing/selftests/bpf/prog_tests/cgroup_attach

   1// SPDX-License-Identifier: GPL-2.0
   2
   3#include <test_progs.h>
   4
   5#include "cgroup_helpers.h"
   6
   7#define PING_CMD        "ping -q -c1 -w1 127.0.0.1 > /dev/null"
   8
   9static char bpf_log_buf[BPF_LOG_BUF_SIZE];
  10
  11static int map_fd = -1;
  12
  13static int prog_load_cnt(int verdict, int val)
  14{
  15        int cgroup_storage_fd, percpu_cgroup_storage_fd;
  16
  17        if (map_fd < 0)
  18                map_fd = bpf_create_map(BPF_MAP_TYPE_ARRAY, 4, 8, 1, 0);
  19        if (map_fd < 0) {
  20                printf("failed to create map '%s'\n", strerror(errno));
  21                return -1;
  22        }
  23
  24        cgroup_storage_fd = bpf_create_map(BPF_MAP_TYPE_CGROUP_STORAGE,
  25                                sizeof(struct bpf_cgroup_storage_key), 8, 0, 0);
  26        if (cgroup_storage_fd < 0) {
  27                printf("failed to create map '%s'\n", strerror(errno));
  28                return -1;
  29        }
  30
  31        percpu_cgroup_storage_fd = bpf_create_map(
  32                BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE,
  33                sizeof(struct bpf_cgroup_storage_key), 8, 0, 0);
  34        if (percpu_cgroup_storage_fd < 0) {
  35                printf("failed to create map '%s'\n", strerror(errno));
  36                return -1;
  37        }
  38
  39        struct bpf_insn prog[] = {
  40                BPF_MOV32_IMM(BPF_REG_0, 0),
  41                BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_0, -4), /* *(u32 *)(fp - 4) = r0 */
  42                BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
  43                BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -4), /* r2 = fp - 4 */
  44                BPF_LD_MAP_FD(BPF_REG_1, map_fd),
  45                BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
  46                BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
  47                BPF_MOV64_IMM(BPF_REG_1, val), /* r1 = 1 */
  48                BPF_ATOMIC_OP(BPF_DW, BPF_ADD, BPF_REG_0, BPF_REG_1, 0),
  49
  50                BPF_LD_MAP_FD(BPF_REG_1, cgroup_storage_fd),
  51                BPF_MOV64_IMM(BPF_REG_2, 0),
  52                BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_get_local_storage),
  53                BPF_MOV64_IMM(BPF_REG_1, val),
  54                BPF_ATOMIC_OP(BPF_W, BPF_ADD, BPF_REG_0, BPF_REG_1, 0),
  55
  56                BPF_LD_MAP_FD(BPF_REG_1, percpu_cgroup_storage_fd),
  57                BPF_MOV64_IMM(BPF_REG_2, 0),
  58                BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_get_local_storage),
  59                BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_0, 0),
  60                BPF_ALU64_IMM(BPF_ADD, BPF_REG_3, 0x1),
  61                BPF_STX_MEM(BPF_W, BPF_REG_0, BPF_REG_3, 0),
  62
  63                BPF_MOV64_IMM(BPF_REG_0, verdict), /* r0 = verdict */
  64                BPF_EXIT_INSN(),
  65        };
  66        size_t insns_cnt = sizeof(prog) / sizeof(struct bpf_insn);
  67        int ret;
  68
  69        ret = bpf_load_program(BPF_PROG_TYPE_CGROUP_SKB,
  70                               prog, insns_cnt, "GPL", 0,
  71                               bpf_log_buf, BPF_LOG_BUF_SIZE);
  72
  73        close(cgroup_storage_fd);
  74        return ret;
  75}
  76
  77void test_cgroup_attach_multi(void)
  78{
  79        __u32 prog_ids[4], prog_cnt = 0, attach_flags, saved_prog_id;
  80        int cg1 = 0, cg2 = 0, cg3 = 0, cg4 = 0, cg5 = 0, key = 0;
  81        DECLARE_LIBBPF_OPTS(bpf_prog_attach_opts, attach_opts);
  82        int allow_prog[7] = {-1};
  83        unsigned long long value;
  84        __u32 duration = 0;
  85        int i = 0;
  86
  87        for (i = 0; i < ARRAY_SIZE(allow_prog); i++) {
  88                allow_prog[i] = prog_load_cnt(1, 1 << i);
  89                if (CHECK(allow_prog[i] < 0, "prog_load",
  90                          "verifier output:\n%s\n-------\n", bpf_log_buf))
  91                        goto err;
  92        }
  93
  94        if (CHECK_FAIL(setup_cgroup_environment()))
  95                goto err;
  96
  97        cg1 = create_and_get_cgroup("/cg1");
  98        if (CHECK_FAIL(cg1 < 0))
  99                goto err;
 100        cg2 = create_and_get_cgroup("/cg1/cg2");
 101        if (CHECK_FAIL(cg2 < 0))
 102                goto err;
 103        cg3 = create_and_get_cgroup("/cg1/cg2/cg3");
 104        if (CHECK_FAIL(cg3 < 0))
 105                goto err;
 106        cg4 = create_and_get_cgroup("/cg1/cg2/cg3/cg4");
 107        if (CHECK_FAIL(cg4 < 0))
 108                goto err;
 109        cg5 = create_and_get_cgroup("/cg1/cg2/cg3/cg4/cg5");
 110        if (CHECK_FAIL(cg5 < 0))
 111                goto err;
 112
 113        if (CHECK_FAIL(join_cgroup("/cg1/cg2/cg3/cg4/cg5")))
 114                goto err;
 115
 116        if (CHECK(bpf_prog_attach(allow_prog[0], cg1, BPF_CGROUP_INET_EGRESS,
 117                                  BPF_F_ALLOW_MULTI),
 118                  "prog0_attach_to_cg1_multi", "errno=%d\n", errno))
 119                goto err;
 120
 121        if (CHECK(!bpf_prog_attach(allow_prog[0], cg1, BPF_CGROUP_INET_EGRESS,
 122                                   BPF_F_ALLOW_MULTI),
 123                  "fail_same_prog_attach_to_cg1", "unexpected success\n"))
 124                goto err;
 125
 126        if (CHECK(bpf_prog_attach(allow_prog[1], cg1, BPF_CGROUP_INET_EGRESS,
 127                                  BPF_F_ALLOW_MULTI),
 128                  "prog1_attach_to_cg1_multi", "errno=%d\n", errno))
 129                goto err;
 130
 131        if (CHECK(bpf_prog_attach(allow_prog[2], cg2, BPF_CGROUP_INET_EGRESS,
 132                                  BPF_F_ALLOW_OVERRIDE),
 133                  "prog2_attach_to_cg2_override", "errno=%d\n", errno))
 134                goto err;
 135
 136        if (CHECK(bpf_prog_attach(allow_prog[3], cg3, BPF_CGROUP_INET_EGRESS,
 137                                  BPF_F_ALLOW_MULTI),
 138                  "prog3_attach_to_cg3_multi", "errno=%d\n", errno))
 139                goto err;
 140
 141        if (CHECK(bpf_prog_attach(allow_prog[4], cg4, BPF_CGROUP_INET_EGRESS,
 142                            BPF_F_ALLOW_OVERRIDE),
 143                  "prog4_attach_to_cg4_override", "errno=%d\n", errno))
 144                goto err;
 145
 146        if (CHECK(bpf_prog_attach(allow_prog[5], cg5, BPF_CGROUP_INET_EGRESS, 0),
 147                  "prog5_attach_to_cg5_none", "errno=%d\n", errno))
 148                goto err;
 149
 150        CHECK_FAIL(system(PING_CMD));
 151        CHECK_FAIL(bpf_map_lookup_elem(map_fd, &key, &value));
 152        CHECK_FAIL(value != 1 + 2 + 8 + 32);
 153
 154        /* query the number of effective progs in cg5 */
 155        CHECK_FAIL(bpf_prog_query(cg5, BPF_CGROUP_INET_EGRESS,
 156                                  BPF_F_QUERY_EFFECTIVE, NULL, NULL, &prog_cnt));
 157        CHECK_FAIL(prog_cnt != 4);
 158        /* retrieve prog_ids of effective progs in cg5 */
 159        CHECK_FAIL(bpf_prog_query(cg5, BPF_CGROUP_INET_EGRESS,
 160                                  BPF_F_QUERY_EFFECTIVE, &attach_flags,
 161                                  prog_ids, &prog_cnt));
 162        CHECK_FAIL(prog_cnt != 4);
 163        CHECK_FAIL(attach_flags != 0);
 164        saved_prog_id = prog_ids[0];
 165        /* check enospc handling */
 166        prog_ids[0] = 0;
 167        prog_cnt = 2;
 168        CHECK_FAIL(bpf_prog_query(cg5, BPF_CGROUP_INET_EGRESS,
 169                                  BPF_F_QUERY_EFFECTIVE, &attach_flags,
 170                                  prog_ids, &prog_cnt) >= 0);
 171        CHECK_FAIL(errno != ENOSPC);
 172        CHECK_FAIL(prog_cnt != 4);
 173        /* check that prog_ids are returned even when buffer is too small */
 174        CHECK_FAIL(prog_ids[0] != saved_prog_id);
 175        /* retrieve prog_id of single attached prog in cg5 */
 176        prog_ids[0] = 0;
 177        CHECK_FAIL(bpf_prog_query(cg5, BPF_CGROUP_INET_EGRESS, 0, NULL,
 178                                  prog_ids, &prog_cnt));
 179        CHECK_FAIL(prog_cnt != 1);
 180        CHECK_FAIL(prog_ids[0] != saved_prog_id);
 181
 182        /* detach bottom program and ping again */
 183        if (CHECK(bpf_prog_detach2(-1, cg5, BPF_CGROUP_INET_EGRESS),
 184                  "prog_detach_from_cg5", "errno=%d\n", errno))
 185                goto err;
 186
 187        value = 0;
 188        CHECK_FAIL(bpf_map_update_elem(map_fd, &key, &value, 0));
 189        CHECK_FAIL(system(PING_CMD));
 190        CHECK_FAIL(bpf_map_lookup_elem(map_fd, &key, &value));
 191        CHECK_FAIL(value != 1 + 2 + 8 + 16);
 192
 193        /* test replace */
 194
 195        attach_opts.flags = BPF_F_ALLOW_OVERRIDE | BPF_F_REPLACE;
 196        attach_opts.replace_prog_fd = allow_prog[0];
 197        if (CHECK(!bpf_prog_attach_xattr(allow_prog[6], cg1,
 198                                         BPF_CGROUP_INET_EGRESS, &attach_opts),
 199                  "fail_prog_replace_override", "unexpected success\n"))
 200                goto err;
 201        CHECK_FAIL(errno != EINVAL);
 202
 203        attach_opts.flags = BPF_F_REPLACE;
 204        if (CHECK(!bpf_prog_attach_xattr(allow_prog[6], cg1,
 205                                         BPF_CGROUP_INET_EGRESS, &attach_opts),
 206                  "fail_prog_replace_no_multi", "unexpected success\n"))
 207                goto err;
 208        CHECK_FAIL(errno != EINVAL);
 209
 210        attach_opts.flags = BPF_F_ALLOW_MULTI | BPF_F_REPLACE;
 211        attach_opts.replace_prog_fd = -1;
 212        if (CHECK(!bpf_prog_attach_xattr(allow_prog[6], cg1,
 213                                         BPF_CGROUP_INET_EGRESS, &attach_opts),
 214                  "fail_prog_replace_bad_fd", "unexpected success\n"))
 215                goto err;
 216        CHECK_FAIL(errno != EBADF);
 217
 218        /* replacing a program that is not attached to cgroup should fail  */
 219        attach_opts.replace_prog_fd = allow_prog[3];
 220        if (CHECK(!bpf_prog_attach_xattr(allow_prog[6], cg1,
 221                                         BPF_CGROUP_INET_EGRESS, &attach_opts),
 222                  "fail_prog_replace_no_ent", "unexpected success\n"))
 223                goto err;
 224        CHECK_FAIL(errno != ENOENT);
 225
 226        /* replace 1st from the top program */
 227        attach_opts.replace_prog_fd = allow_prog[0];
 228        if (CHECK(bpf_prog_attach_xattr(allow_prog[6], cg1,
 229                                        BPF_CGROUP_INET_EGRESS, &attach_opts),
 230                  "prog_replace", "errno=%d\n", errno))
 231                goto err;
 232
 233        /* replace program with itself */
 234        attach_opts.replace_prog_fd = allow_prog[6];
 235        if (CHECK(bpf_prog_attach_xattr(allow_prog[6], cg1,
 236                                        BPF_CGROUP_INET_EGRESS, &attach_opts),
 237                  "prog_replace", "errno=%d\n", errno))
 238                goto err;
 239
 240        value = 0;
 241        CHECK_FAIL(bpf_map_update_elem(map_fd, &key, &value, 0));
 242        CHECK_FAIL(system(PING_CMD));
 243        CHECK_FAIL(bpf_map_lookup_elem(map_fd, &key, &value));
 244        CHECK_FAIL(value != 64 + 2 + 8 + 16);
 245
 246        /* detach 3rd from bottom program and ping again */
 247        if (CHECK(!bpf_prog_detach2(0, cg3, BPF_CGROUP_INET_EGRESS),
 248                  "fail_prog_detach_from_cg3", "unexpected success\n"))
 249                goto err;
 250
 251        if (CHECK(bpf_prog_detach2(allow_prog[3], cg3, BPF_CGROUP_INET_EGRESS),
 252                  "prog3_detach_from_cg3", "errno=%d\n", errno))
 253                goto err;
 254
 255        value = 0;
 256        CHECK_FAIL(bpf_map_update_elem(map_fd, &key, &value, 0));
 257        CHECK_FAIL(system(PING_CMD));
 258        CHECK_FAIL(bpf_map_lookup_elem(map_fd, &key, &value));
 259        CHECK_FAIL(value != 64 + 2 + 16);
 260
 261        /* detach 2nd from bottom program and ping again */
 262        if (CHECK(bpf_prog_detach2(-1, cg4, BPF_CGROUP_INET_EGRESS),
 263                  "prog_detach_from_cg4", "errno=%d\n", errno))
 264                goto err;
 265
 266        value = 0;
 267        CHECK_FAIL(bpf_map_update_elem(map_fd, &key, &value, 0));
 268        CHECK_FAIL(system(PING_CMD));
 269        CHECK_FAIL(bpf_map_lookup_elem(map_fd, &key, &value));
 270        CHECK_FAIL(value != 64 + 2 + 4);
 271
 272        prog_cnt = 4;
 273        CHECK_FAIL(bpf_prog_query(cg5, BPF_CGROUP_INET_EGRESS,
 274                                  BPF_F_QUERY_EFFECTIVE, &attach_flags,
 275                                  prog_ids, &prog_cnt));
 276        CHECK_FAIL(prog_cnt != 3);
 277        CHECK_FAIL(attach_flags != 0);
 278        CHECK_FAIL(bpf_prog_query(cg5, BPF_CGROUP_INET_EGRESS, 0, NULL,
 279                                  prog_ids, &prog_cnt));
 280        CHECK_FAIL(prog_cnt != 0);
 281
 282err:
 283        for (i = 0; i < ARRAY_SIZE(allow_prog); i++)
 284                if (allow_prog[i] >= 0)
 285                        close(allow_prog[i]);
 286        close(cg1);
 287        close(cg2);
 288        close(cg3);
 289        close(cg4);
 290        close(cg5);
 291        cleanup_cgroup_environment();
 292}
 293