diff options
Diffstat (limited to 'tools/testing/selftests/bpf/test_loader.c')
-rw-r--r-- | tools/testing/selftests/bpf/test_loader.c | 536 |
1 files changed, 453 insertions, 83 deletions
diff --git a/tools/testing/selftests/bpf/test_loader.c b/tools/testing/selftests/bpf/test_loader.c index bf41390157bf..47e9e076bc8f 100644 --- a/tools/testing/selftests/bpf/test_loader.c +++ b/tools/testing/selftests/bpf/test_loader.c @@ -1,9 +1,14 @@ // SPDX-License-Identifier: GPL-2.0-only /* Copyright (c) 2022 Meta Platforms, Inc. and affiliates. */ +#include <linux/capability.h> #include <stdlib.h> #include <test_progs.h> #include <bpf/btf.h> +#include "autoconf_helper.h" +#include "unpriv_helpers.h" +#include "cap_helpers.h" + #define str_has_pfx(str, pfx) \ (strncmp(str, pfx, __builtin_constant_p(pfx) ? sizeof(pfx) - 1 : strlen(pfx)) == 0) @@ -12,16 +17,48 @@ #define TEST_TAG_EXPECT_FAILURE "comment:test_expect_failure" #define TEST_TAG_EXPECT_SUCCESS "comment:test_expect_success" #define TEST_TAG_EXPECT_MSG_PFX "comment:test_expect_msg=" +#define TEST_TAG_EXPECT_FAILURE_UNPRIV "comment:test_expect_failure_unpriv" +#define TEST_TAG_EXPECT_SUCCESS_UNPRIV "comment:test_expect_success_unpriv" +#define TEST_TAG_EXPECT_MSG_PFX_UNPRIV "comment:test_expect_msg_unpriv=" #define TEST_TAG_LOG_LEVEL_PFX "comment:test_log_level=" #define TEST_TAG_PROG_FLAGS_PFX "comment:test_prog_flags=" +#define TEST_TAG_DESCRIPTION_PFX "comment:test_description=" +#define TEST_TAG_RETVAL_PFX "comment:test_retval=" +#define TEST_TAG_RETVAL_PFX_UNPRIV "comment:test_retval_unpriv=" -struct test_spec { - const char *name; +/* Warning: duplicated in bpf_misc.h */ +#define POINTER_VALUE 0xcafe4all +#define TEST_DATA_LEN 64 + +#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS +#define EFFICIENT_UNALIGNED_ACCESS 1 +#else +#define EFFICIENT_UNALIGNED_ACCESS 0 +#endif + +static int sysctl_unpriv_disabled = -1; + +enum mode { + PRIV = 1, + UNPRIV = 2 +}; + +struct test_subspec { + char *name; bool expect_failure; const char **expect_msgs; size_t expect_msg_cnt; + int retval; + bool execute; +}; + +struct test_spec { + const char *prog_name; + struct test_subspec priv; + struct test_subspec unpriv; int log_level; int prog_flags; + int mode_mask; }; static int tester_init(struct test_loader *tester) @@ -44,17 +81,87 @@ void test_loader_fini(struct test_loader *tester) free(tester->log_buf); } +static void free_test_spec(struct test_spec *spec) +{ + free(spec->priv.name); + free(spec->unpriv.name); + free(spec->priv.expect_msgs); + free(spec->unpriv.expect_msgs); +} + +static int push_msg(const char *msg, struct test_subspec *subspec) +{ + void *tmp; + + tmp = realloc(subspec->expect_msgs, (1 + subspec->expect_msg_cnt) * sizeof(void *)); + if (!tmp) { + ASSERT_FAIL("failed to realloc memory for messages\n"); + return -ENOMEM; + } + subspec->expect_msgs = tmp; + subspec->expect_msgs[subspec->expect_msg_cnt++] = msg; + + return 0; +} + +static int parse_int(const char *str, int *val, const char *name) +{ + char *end; + long tmp; + + errno = 0; + if (str_has_pfx(str, "0x")) + tmp = strtol(str + 2, &end, 16); + else + tmp = strtol(str, &end, 10); + if (errno || end[0] != '\0') { + PRINT_FAIL("failed to parse %s from '%s'\n", name, str); + return -EINVAL; + } + *val = tmp; + return 0; +} + +static int parse_retval(const char *str, int *val, const char *name) +{ + struct { + char *name; + int val; + } named_values[] = { + { "INT_MIN" , INT_MIN }, + { "POINTER_VALUE", POINTER_VALUE }, + { "TEST_DATA_LEN", TEST_DATA_LEN }, + }; + int i; + + for (i = 0; i < ARRAY_SIZE(named_values); ++i) { + if (strcmp(str, named_values[i].name) != 0) + continue; + *val = named_values[i].val; + return 0; + } + + return parse_int(str, val, name); +} + +/* Uses btf_decl_tag attributes to describe the expected test + * behavior, see bpf_misc.h for detailed description of each attribute + * and attribute combinations. + */ static int parse_test_spec(struct test_loader *tester, struct bpf_object *obj, struct bpf_program *prog, struct test_spec *spec) { + const char *description = NULL; + bool has_unpriv_result = false; + bool has_unpriv_retval = false; + int func_id, i, err = 0; struct btf *btf; - int func_id, i; memset(spec, 0, sizeof(*spec)); - spec->name = bpf_program__name(prog); + spec->prog_name = bpf_program__name(prog); btf = bpf_object__btf(obj); if (!btf) { @@ -62,16 +169,16 @@ static int parse_test_spec(struct test_loader *tester, return -EINVAL; } - func_id = btf__find_by_name_kind(btf, spec->name, BTF_KIND_FUNC); + func_id = btf__find_by_name_kind(btf, spec->prog_name, BTF_KIND_FUNC); if (func_id < 0) { - ASSERT_FAIL("failed to find FUNC BTF type for '%s'", spec->name); + ASSERT_FAIL("failed to find FUNC BTF type for '%s'", spec->prog_name); return -EINVAL; } for (i = 1; i < btf__type_cnt(btf); i++) { + const char *s, *val, *msg; const struct btf_type *t; - const char *s, *val; - char *e; + int tmp; t = btf__type_by_id(btf, i); if (!btf_is_decl_tag(t)) @@ -81,31 +188,54 @@ static int parse_test_spec(struct test_loader *tester, continue; s = btf__str_by_offset(btf, t->name_off); - if (strcmp(s, TEST_TAG_EXPECT_FAILURE) == 0) { - spec->expect_failure = true; + if (str_has_pfx(s, TEST_TAG_DESCRIPTION_PFX)) { + description = s + sizeof(TEST_TAG_DESCRIPTION_PFX) - 1; + } else if (strcmp(s, TEST_TAG_EXPECT_FAILURE) == 0) { + spec->priv.expect_failure = true; + spec->mode_mask |= PRIV; } else if (strcmp(s, TEST_TAG_EXPECT_SUCCESS) == 0) { - spec->expect_failure = false; + spec->priv.expect_failure = false; + spec->mode_mask |= PRIV; + } else if (strcmp(s, TEST_TAG_EXPECT_FAILURE_UNPRIV) == 0) { + spec->unpriv.expect_failure = true; + spec->mode_mask |= UNPRIV; + has_unpriv_result = true; + } else if (strcmp(s, TEST_TAG_EXPECT_SUCCESS_UNPRIV) == 0) { + spec->unpriv.expect_failure = false; + spec->mode_mask |= UNPRIV; + has_unpriv_result = true; } else if (str_has_pfx(s, TEST_TAG_EXPECT_MSG_PFX)) { - void *tmp; - const char **msg; - - tmp = realloc(spec->expect_msgs, - (1 + spec->expect_msg_cnt) * sizeof(void *)); - if (!tmp) { - ASSERT_FAIL("failed to realloc memory for messages\n"); - return -ENOMEM; - } - spec->expect_msgs = tmp; - msg = &spec->expect_msgs[spec->expect_msg_cnt++]; - *msg = s + sizeof(TEST_TAG_EXPECT_MSG_PFX) - 1; + msg = s + sizeof(TEST_TAG_EXPECT_MSG_PFX) - 1; + err = push_msg(msg, &spec->priv); + if (err) + goto cleanup; + spec->mode_mask |= PRIV; + } else if (str_has_pfx(s, TEST_TAG_EXPECT_MSG_PFX_UNPRIV)) { + msg = s + sizeof(TEST_TAG_EXPECT_MSG_PFX_UNPRIV) - 1; + err = push_msg(msg, &spec->unpriv); + if (err) + goto cleanup; + spec->mode_mask |= UNPRIV; + } else if (str_has_pfx(s, TEST_TAG_RETVAL_PFX)) { + val = s + sizeof(TEST_TAG_RETVAL_PFX) - 1; + err = parse_retval(val, &spec->priv.retval, "__retval"); + if (err) + goto cleanup; + spec->priv.execute = true; + spec->mode_mask |= PRIV; + } else if (str_has_pfx(s, TEST_TAG_RETVAL_PFX_UNPRIV)) { + val = s + sizeof(TEST_TAG_RETVAL_PFX_UNPRIV) - 1; + err = parse_retval(val, &spec->unpriv.retval, "__retval_unpriv"); + if (err) + goto cleanup; + spec->mode_mask |= UNPRIV; + spec->unpriv.execute = true; + has_unpriv_retval = true; } else if (str_has_pfx(s, TEST_TAG_LOG_LEVEL_PFX)) { val = s + sizeof(TEST_TAG_LOG_LEVEL_PFX) - 1; - errno = 0; - spec->log_level = strtol(val, &e, 0); - if (errno || e[0] != '\0') { - ASSERT_FAIL("failed to parse test log level from '%s'", s); - return -EINVAL; - } + err = parse_int(val, &spec->log_level, "test log level"); + if (err) + goto cleanup; } else if (str_has_pfx(s, TEST_TAG_PROG_FLAGS_PFX)) { val = s + sizeof(TEST_TAG_PROG_FLAGS_PFX) - 1; if (strcmp(val, "BPF_F_STRICT_ALIGNMENT") == 0) { @@ -121,17 +251,74 @@ static int parse_test_spec(struct test_loader *tester, } else if (strcmp(val, "BPF_F_XDP_HAS_FRAGS") == 0) { spec->prog_flags |= BPF_F_XDP_HAS_FRAGS; } else /* assume numeric value */ { - errno = 0; - spec->prog_flags |= strtol(val, &e, 0); - if (errno || e[0] != '\0') { - ASSERT_FAIL("failed to parse test prog flags from '%s'", s); - return -EINVAL; - } + err = parse_int(val, &tmp, "test prog flags"); + if (err) + goto cleanup; + spec->prog_flags |= tmp; + } + } + } + + if (spec->mode_mask == 0) + spec->mode_mask = PRIV; + + if (!description) + description = spec->prog_name; + + if (spec->mode_mask & PRIV) { + spec->priv.name = strdup(description); + if (!spec->priv.name) { + PRINT_FAIL("failed to allocate memory for priv.name\n"); + err = -ENOMEM; + goto cleanup; + } + } + + if (spec->mode_mask & UNPRIV) { + int descr_len = strlen(description); + const char *suffix = " @unpriv"; + char *name; + + name = malloc(descr_len + strlen(suffix) + 1); + if (!name) { + PRINT_FAIL("failed to allocate memory for unpriv.name\n"); + err = -ENOMEM; + goto cleanup; + } + + strcpy(name, description); + strcpy(&name[descr_len], suffix); + spec->unpriv.name = name; + } + + if (spec->mode_mask & (PRIV | UNPRIV)) { + if (!has_unpriv_result) + spec->unpriv.expect_failure = spec->priv.expect_failure; + + if (!has_unpriv_retval) { + spec->unpriv.retval = spec->priv.retval; + spec->unpriv.execute = spec->priv.execute; + } + + if (!spec->unpriv.expect_msgs) { + size_t sz = spec->priv.expect_msg_cnt * sizeof(void *); + + spec->unpriv.expect_msgs = malloc(sz); + if (!spec->unpriv.expect_msgs) { + PRINT_FAIL("failed to allocate memory for unpriv.expect_msgs\n"); + err = -ENOMEM; + goto cleanup; } + memcpy(spec->unpriv.expect_msgs, spec->priv.expect_msgs, sz); + spec->unpriv.expect_msg_cnt = spec->priv.expect_msg_cnt; } } return 0; + +cleanup: + free_test_spec(spec); + return err; } static void prepare_case(struct test_loader *tester, @@ -148,7 +335,7 @@ static void prepare_case(struct test_loader *tester, bpf_program__set_log_buf(prog, tester->log_buf, tester->log_buf_sz); - /* Make sure we set at least minimal log level, unless test requirest + /* Make sure we set at least minimal log level, unless test requires * even higher level already. Make sure to preserve independent log * level 4 (verifier stats), though. */ @@ -172,18 +359,18 @@ static void emit_verifier_log(const char *log_buf, bool force) } static void validate_case(struct test_loader *tester, - struct test_spec *spec, + struct test_subspec *subspec, struct bpf_object *obj, struct bpf_program *prog, int load_err) { int i, j; - for (i = 0; i < spec->expect_msg_cnt; i++) { + for (i = 0; i < subspec->expect_msg_cnt; i++) { char *match; const char *expect_msg; - expect_msg = spec->expect_msgs[i]; + expect_msg = subspec->expect_msgs[i]; match = strstr(tester->log_buf + tester->next_match_pos, expect_msg); if (!ASSERT_OK_PTR(match, "expect_msg")) { @@ -191,7 +378,8 @@ static void validate_case(struct test_loader *tester, if (env.verbosity == VERBOSE_NONE) emit_verifier_log(tester->log_buf, true /*force*/); for (j = 0; j < i; j++) - fprintf(stderr, "MATCHED MSG: '%s'\n", spec->expect_msgs[j]); + fprintf(stderr, + "MATCHED MSG: '%s'\n", subspec->expect_msgs[j]); fprintf(stderr, "EXPECTED MSG: '%s'\n", expect_msg); return; } @@ -200,17 +388,229 @@ static void validate_case(struct test_loader *tester, } } +struct cap_state { + __u64 old_caps; + bool initialized; +}; + +static int drop_capabilities(struct cap_state *caps) +{ + const __u64 caps_to_drop = (1ULL << CAP_SYS_ADMIN | 1ULL << CAP_NET_ADMIN | + 1ULL << CAP_PERFMON | 1ULL << CAP_BPF); + int err; + + err = cap_disable_effective(caps_to_drop, &caps->old_caps); + if (err) { + PRINT_FAIL("failed to drop capabilities: %i, %s\n", err, strerror(err)); + return err; + } + + caps->initialized = true; + return 0; +} + +static int restore_capabilities(struct cap_state *caps) +{ + int err; + + if (!caps->initialized) + return 0; + + err = cap_enable_effective(caps->old_caps, NULL); + if (err) + PRINT_FAIL("failed to restore capabilities: %i, %s\n", err, strerror(err)); + caps->initialized = false; + return err; +} + +static bool can_execute_unpriv(struct test_loader *tester, struct test_spec *spec) +{ + if (sysctl_unpriv_disabled < 0) + sysctl_unpriv_disabled = get_unpriv_disabled() ? 1 : 0; + if (sysctl_unpriv_disabled) + return false; + if ((spec->prog_flags & BPF_F_ANY_ALIGNMENT) && !EFFICIENT_UNALIGNED_ACCESS) + return false; + return true; +} + +static bool is_unpriv_capable_map(struct bpf_map *map) +{ + enum bpf_map_type type; + __u32 flags; + + type = bpf_map__type(map); + + switch (type) { + case BPF_MAP_TYPE_HASH: + case BPF_MAP_TYPE_PERCPU_HASH: + case BPF_MAP_TYPE_HASH_OF_MAPS: + flags = bpf_map__map_flags(map); + return !(flags & BPF_F_ZERO_SEED); + case BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE: + case BPF_MAP_TYPE_ARRAY: + case BPF_MAP_TYPE_RINGBUF: + case BPF_MAP_TYPE_PROG_ARRAY: + case BPF_MAP_TYPE_CGROUP_ARRAY: + case BPF_MAP_TYPE_PERCPU_ARRAY: + case BPF_MAP_TYPE_USER_RINGBUF: + case BPF_MAP_TYPE_ARRAY_OF_MAPS: + case BPF_MAP_TYPE_CGROUP_STORAGE: + case BPF_MAP_TYPE_PERF_EVENT_ARRAY: + return true; + default: + return false; + } +} + +static int do_prog_test_run(int fd_prog, int *retval) +{ + __u8 tmp_out[TEST_DATA_LEN << 2] = {}; + __u8 tmp_in[TEST_DATA_LEN] = {}; + int err, saved_errno; + LIBBPF_OPTS(bpf_test_run_opts, topts, + .data_in = tmp_in, + .data_size_in = sizeof(tmp_in), + .data_out = tmp_out, + .data_size_out = sizeof(tmp_out), + .repeat = 1, + ); + + err = bpf_prog_test_run_opts(fd_prog, &topts); + saved_errno = errno; + + if (err) { + PRINT_FAIL("FAIL: Unexpected bpf_prog_test_run error: %d (%s) ", + saved_errno, strerror(saved_errno)); + return err; + } + + ASSERT_OK(0, "bpf_prog_test_run"); + *retval = topts.retval; + + return 0; +} + +static bool should_do_test_run(struct test_spec *spec, struct test_subspec *subspec) +{ + if (!subspec->execute) + return false; + + if (subspec->expect_failure) + return false; + + if ((spec->prog_flags & BPF_F_ANY_ALIGNMENT) && !EFFICIENT_UNALIGNED_ACCESS) { + if (env.verbosity != VERBOSE_NONE) + printf("alignment prevents execution\n"); + return false; + } + + return true; +} + /* this function is forced noinline and has short generic name to look better * in test_progs output (in case of a failure) */ static noinline void run_subtest(struct test_loader *tester, - const char *skel_name, - skel_elf_bytes_fn elf_bytes_factory) + struct bpf_object_open_opts *open_opts, + const void *obj_bytes, + size_t obj_byte_cnt, + struct test_spec *spec, + bool unpriv) +{ + struct test_subspec *subspec = unpriv ? &spec->unpriv : &spec->priv; + struct cap_state caps = {}; + struct bpf_program *tprog; + struct bpf_object *tobj; + struct bpf_map *map; + int retval; + int err; + + if (!test__start_subtest(subspec->name)) + return; + + if (unpriv) { + if (!can_execute_unpriv(tester, spec)) { + test__skip(); + test__end_subtest(); + return; + } + if (drop_capabilities(&caps)) { + test__end_subtest(); + return; + } + } + + tobj = bpf_object__open_mem(obj_bytes, obj_byte_cnt, open_opts); + if (!ASSERT_OK_PTR(tobj, "obj_open_mem")) /* shouldn't happen */ + goto subtest_cleanup; + + bpf_object__for_each_program(tprog, tobj) + bpf_program__set_autoload(tprog, false); + + bpf_object__for_each_program(tprog, tobj) { + /* only load specified program */ + if (strcmp(bpf_program__name(tprog), spec->prog_name) == 0) { + bpf_program__set_autoload(tprog, true); + break; + } + } + + prepare_case(tester, spec, tobj, tprog); + + /* By default bpf_object__load() automatically creates all + * maps declared in the skeleton. Some map types are only + * allowed in priv mode. Disable autoload for such maps in + * unpriv mode. + */ + bpf_object__for_each_map(map, tobj) + bpf_map__set_autocreate(map, !unpriv || is_unpriv_capable_map(map)); + + err = bpf_object__load(tobj); + if (subspec->expect_failure) { + if (!ASSERT_ERR(err, "unexpected_load_success")) { + emit_verifier_log(tester->log_buf, false /*force*/); + goto tobj_cleanup; + } + } else { + if (!ASSERT_OK(err, "unexpected_load_failure")) { + emit_verifier_log(tester->log_buf, true /*force*/); + goto tobj_cleanup; + } + } + + emit_verifier_log(tester->log_buf, false /*force*/); + validate_case(tester, subspec, tobj, tprog, err); + + if (should_do_test_run(spec, subspec)) { + /* For some reason test_verifier executes programs + * with all capabilities restored. Do the same here. + */ + if (!restore_capabilities(&caps)) + goto tobj_cleanup; + + do_prog_test_run(bpf_program__fd(tprog), &retval); + if (retval != subspec->retval && subspec->retval != POINTER_VALUE) { + PRINT_FAIL("Unexpected retval: %d != %d\n", retval, subspec->retval); + goto tobj_cleanup; + } + } + +tobj_cleanup: + bpf_object__close(tobj); +subtest_cleanup: + test__end_subtest(); + restore_capabilities(&caps); +} + +static void process_subtest(struct test_loader *tester, + const char *skel_name, + skel_elf_bytes_fn elf_bytes_factory) { LIBBPF_OPTS(bpf_object_open_opts, open_opts, .object_name = skel_name); - struct bpf_object *obj = NULL, *tobj; - struct bpf_program *prog, *tprog; + struct bpf_object *obj = NULL; + struct bpf_program *prog; const void *obj_bytes; size_t obj_byte_cnt; int err; @@ -224,52 +624,22 @@ void run_subtest(struct test_loader *tester, return; bpf_object__for_each_program(prog, obj) { - const char *prog_name = bpf_program__name(prog); struct test_spec spec; - if (!test__start_subtest(prog_name)) - continue; - /* if we can't derive test specification, go to the next test */ err = parse_test_spec(tester, obj, prog, &spec); - if (!ASSERT_OK(err, "parse_test_spec")) + if (err) { + PRINT_FAIL("Can't parse test spec for program '%s'\n", + bpf_program__name(prog)); continue; - - tobj = bpf_object__open_mem(obj_bytes, obj_byte_cnt, &open_opts); - if (!ASSERT_OK_PTR(tobj, "obj_open_mem")) /* shouldn't happen */ - continue; - - bpf_object__for_each_program(tprog, tobj) - bpf_program__set_autoload(tprog, false); - - bpf_object__for_each_program(tprog, tobj) { - /* only load specified program */ - if (strcmp(bpf_program__name(tprog), prog_name) == 0) { - bpf_program__set_autoload(tprog, true); - break; - } - } - - prepare_case(tester, &spec, tobj, tprog); - - err = bpf_object__load(tobj); - if (spec.expect_failure) { - if (!ASSERT_ERR(err, "unexpected_load_success")) { - emit_verifier_log(tester->log_buf, false /*force*/); - goto tobj_cleanup; - } - } else { - if (!ASSERT_OK(err, "unexpected_load_failure")) { - emit_verifier_log(tester->log_buf, true /*force*/); - goto tobj_cleanup; - } } - emit_verifier_log(tester->log_buf, false /*force*/); - validate_case(tester, &spec, tobj, tprog, err); + if (spec.mode_mask & PRIV) + run_subtest(tester, &open_opts, obj_bytes, obj_byte_cnt, &spec, false); + if (spec.mode_mask & UNPRIV) + run_subtest(tester, &open_opts, obj_bytes, obj_byte_cnt, &spec, true); -tobj_cleanup: - bpf_object__close(tobj); + free_test_spec(&spec); } bpf_object__close(obj); @@ -280,5 +650,5 @@ void test_loader__run_subtests(struct test_loader *tester, skel_elf_bytes_fn elf_bytes_factory) { /* see comment in run_subtest() for why we do this function nesting */ - run_subtest(tester, skel_name, elf_bytes_factory); + process_subtest(tester, skel_name, elf_bytes_factory); } |