diff options
| -rw-r--r-- | tools/lib/bpf/libbpf.c | 126 | ||||
| -rw-r--r-- | tools/testing/selftests/bpf/prog_tests/section_names.c | 42 |
2 files changed, 109 insertions, 59 deletions
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index ff9174282a8c..8f480e29a6b0 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -178,6 +178,8 @@ struct bpf_capabilities { __u32 array_mmap:1; /* BTF_FUNC_GLOBAL is supported */ __u32 btf_func_global:1; + /* kernel support for expected_attach_type in BPF_PROG_LOAD */ + __u32 exp_attach_type:1; }; enum reloc_type { @@ -194,6 +196,22 @@ struct reloc_desc { int sym_off; }; +struct bpf_sec_def; + +typedef struct bpf_link *(*attach_fn_t)(const struct bpf_sec_def *sec, + struct bpf_program *prog); + +struct bpf_sec_def { + const char *sec; + size_t len; + enum bpf_prog_type prog_type; + enum bpf_attach_type expected_attach_type; + bool is_exp_attach_type_optional; + bool is_attachable; + bool is_attach_btf; + attach_fn_t attach_fn; +}; + /* * bpf_prog should be a better name but it has been used in * linux/filter.h. @@ -204,6 +222,7 @@ struct bpf_program { char *name; int prog_ifindex; char *section_name; + const struct bpf_sec_def *sec_def; /* section_name with / replaced by _; makes recursive pinning * in bpf_object__pin_programs easier */ @@ -3316,6 +3335,37 @@ static int bpf_object__probe_array_mmap(struct bpf_object *obj) } static int +bpf_object__probe_exp_attach_type(struct bpf_object *obj) +{ + struct bpf_load_program_attr attr; + struct bpf_insn insns[] = { + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }; + int fd; + + memset(&attr, 0, sizeof(attr)); + /* use any valid combination of program type and (optional) + * non-zero expected attach type (i.e., not a BPF_CGROUP_INET_INGRESS) + * to see if kernel supports expected_attach_type field for + * BPF_PROG_LOAD command + */ + attr.prog_type = BPF_PROG_TYPE_CGROUP_SOCK; + attr.expected_attach_type = BPF_CGROUP_INET_SOCK_CREATE; + attr.insns = insns; + attr.insns_cnt = ARRAY_SIZE(insns); + attr.license = "GPL"; + + fd = bpf_load_program_xattr(&attr, NULL, 0); + if (fd >= 0) { + obj->caps.exp_attach_type = 1; + close(fd); + return 1; + } + return 0; +} + +static int bpf_object__probe_caps(struct bpf_object *obj) { int (*probe_fn[])(struct bpf_object *obj) = { @@ -3325,6 +3375,7 @@ bpf_object__probe_caps(struct bpf_object *obj) bpf_object__probe_btf_func_global, bpf_object__probe_btf_datasec, bpf_object__probe_array_mmap, + bpf_object__probe_exp_attach_type, }; int i, ret; @@ -4861,7 +4912,12 @@ load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt, memset(&load_attr, 0, sizeof(struct bpf_load_program_attr)); load_attr.prog_type = prog->type; - load_attr.expected_attach_type = prog->expected_attach_type; + /* old kernels might not support specifying expected_attach_type */ + if (!prog->caps->exp_attach_type && prog->sec_def && + prog->sec_def->is_exp_attach_type_optional) + load_attr.expected_attach_type = 0; + else + load_attr.expected_attach_type = prog->expected_attach_type; if (prog->caps->name) load_attr.name = prog->name; load_attr.insns = insns; @@ -5062,6 +5118,8 @@ bpf_object__load_progs(struct bpf_object *obj, int log_level) return 0; } +static const struct bpf_sec_def *find_sec_def(const char *sec_name); + static struct bpf_object * __bpf_object__open(const char *path, const void *obj_buf, size_t obj_buf_sz, const struct bpf_object_open_opts *opts) @@ -5117,24 +5175,17 @@ __bpf_object__open(const char *path, const void *obj_buf, size_t obj_buf_sz, bpf_object__elf_finish(obj); bpf_object__for_each_program(prog, obj) { - enum bpf_prog_type prog_type; - enum bpf_attach_type attach_type; - - if (prog->type != BPF_PROG_TYPE_UNSPEC) - continue; - - err = libbpf_prog_type_by_name(prog->section_name, &prog_type, - &attach_type); - if (err == -ESRCH) + prog->sec_def = find_sec_def(prog->section_name); + if (!prog->sec_def) /* couldn't guess, but user might manually specify */ continue; - if (err) - goto out; - bpf_program__set_type(prog, prog_type); - bpf_program__set_expected_attach_type(prog, attach_type); - if (prog_type == BPF_PROG_TYPE_TRACING || - prog_type == BPF_PROG_TYPE_EXT) + bpf_program__set_type(prog, prog->sec_def->prog_type); + bpf_program__set_expected_attach_type(prog, + prog->sec_def->expected_attach_type); + + if (prog->sec_def->prog_type == BPF_PROG_TYPE_TRACING || + prog->sec_def->prog_type == BPF_PROG_TYPE_EXT) prog->attach_prog_fd = OPTS_GET(opts, attach_prog_fd, 0); } @@ -6223,23 +6274,32 @@ void bpf_program__set_expected_attach_type(struct bpf_program *prog, prog->expected_attach_type = type; } -#define BPF_PROG_SEC_IMPL(string, ptype, eatype, is_attachable, btf, atype) \ - { string, sizeof(string) - 1, ptype, eatype, is_attachable, btf, atype } +#define BPF_PROG_SEC_IMPL(string, ptype, eatype, eatype_optional, \ + attachable, attach_btf) \ + { \ + .sec = string, \ + .len = sizeof(string) - 1, \ + .prog_type = ptype, \ + .expected_attach_type = eatype, \ + .is_exp_attach_type_optional = eatype_optional, \ + .is_attachable = attachable, \ + .is_attach_btf = attach_btf, \ + } /* Programs that can NOT be attached. */ #define BPF_PROG_SEC(string, ptype) BPF_PROG_SEC_IMPL(string, ptype, 0, 0, 0, 0) /* Programs that can be attached. */ #define BPF_APROG_SEC(string, ptype, atype) \ - BPF_PROG_SEC_IMPL(string, ptype, 0, 1, 0, atype) + BPF_PROG_SEC_IMPL(string, ptype, atype, true, 1, 0) /* Programs that must specify expected attach type at load time. */ #define BPF_EAPROG_SEC(string, ptype, eatype) \ - BPF_PROG_SEC_IMPL(string, ptype, eatype, 1, 0, eatype) + BPF_PROG_SEC_IMPL(string, ptype, eatype, false, 1, 0) /* Programs that use BTF to identify attach point */ #define BPF_PROG_BTF(string, ptype, eatype) \ - BPF_PROG_SEC_IMPL(string, ptype, eatype, 0, 1, 0) + BPF_PROG_SEC_IMPL(string, ptype, eatype, false, 0, 1) /* Programs that can be attached but attach type can't be identified by section * name. Kept for backward compatibility. @@ -6253,11 +6313,6 @@ void bpf_program__set_expected_attach_type(struct bpf_program *prog, __VA_ARGS__ \ } -struct bpf_sec_def; - -typedef struct bpf_link *(*attach_fn_t)(const struct bpf_sec_def *sec, - struct bpf_program *prog); - static struct bpf_link *attach_kprobe(const struct bpf_sec_def *sec, struct bpf_program *prog); static struct bpf_link *attach_tp(const struct bpf_sec_def *sec, @@ -6269,17 +6324,6 @@ static struct bpf_link *attach_trace(const struct bpf_sec_def *sec, static struct bpf_link *attach_lsm(const struct bpf_sec_def *sec, struct bpf_program *prog); -struct bpf_sec_def { - const char *sec; - size_t len; - enum bpf_prog_type prog_type; - enum bpf_attach_type expected_attach_type; - bool is_attachable; - bool is_attach_btf; - enum bpf_attach_type attach_type; - attach_fn_t attach_fn; -}; - static const struct bpf_sec_def section_defs[] = { BPF_PROG_SEC("socket", BPF_PROG_TYPE_SOCKET_FILTER), BPF_PROG_SEC("sk_reuseport", BPF_PROG_TYPE_SK_REUSEPORT), @@ -6713,7 +6757,7 @@ int libbpf_attach_type_by_name(const char *name, continue; if (!section_defs[i].is_attachable) return -EINVAL; - *attach_type = section_defs[i].attach_type; + *attach_type = section_defs[i].expected_attach_type; return 0; } pr_debug("failed to guess attach type based on ELF section name '%s'\n", name); @@ -7542,7 +7586,6 @@ static struct bpf_link *attach_lsm(const struct bpf_sec_def *sec, struct bpf_link * bpf_program__attach_cgroup(struct bpf_program *prog, int cgroup_fd) { - const struct bpf_sec_def *sec_def; enum bpf_attach_type attach_type; char errmsg[STRERR_BUFSIZE]; struct bpf_link *link; @@ -7561,11 +7604,6 @@ bpf_program__attach_cgroup(struct bpf_program *prog, int cgroup_fd) link->detach = &bpf_link__detach_fd; attach_type = bpf_program__get_expected_attach_type(prog); - if (!attach_type) { - sec_def = find_sec_def(bpf_program__title(prog, false)); - if (sec_def) - attach_type = sec_def->attach_type; - } link_fd = bpf_link_create(prog_fd, cgroup_fd, attach_type, NULL); if (link_fd < 0) { link_fd = -errno; diff --git a/tools/testing/selftests/bpf/prog_tests/section_names.c b/tools/testing/selftests/bpf/prog_tests/section_names.c index 9d9351dc2ded..713167449c98 100644 --- a/tools/testing/selftests/bpf/prog_tests/section_names.c +++ b/tools/testing/selftests/bpf/prog_tests/section_names.c @@ -43,18 +43,18 @@ static struct sec_name_test tests[] = { {"lwt_seg6local", {0, BPF_PROG_TYPE_LWT_SEG6LOCAL, 0}, {-EINVAL, 0} }, { "cgroup_skb/ingress", - {0, BPF_PROG_TYPE_CGROUP_SKB, 0}, + {0, BPF_PROG_TYPE_CGROUP_SKB, BPF_CGROUP_INET_INGRESS}, {0, BPF_CGROUP_INET_INGRESS}, }, { "cgroup_skb/egress", - {0, BPF_PROG_TYPE_CGROUP_SKB, 0}, + {0, BPF_PROG_TYPE_CGROUP_SKB, BPF_CGROUP_INET_EGRESS}, {0, BPF_CGROUP_INET_EGRESS}, }, {"cgroup/skb", {0, BPF_PROG_TYPE_CGROUP_SKB, 0}, {-EINVAL, 0} }, { "cgroup/sock", - {0, BPF_PROG_TYPE_CGROUP_SOCK, 0}, + {0, BPF_PROG_TYPE_CGROUP_SOCK, BPF_CGROUP_INET_SOCK_CREATE}, {0, BPF_CGROUP_INET_SOCK_CREATE}, }, { @@ -69,26 +69,38 @@ static struct sec_name_test tests[] = { }, { "cgroup/dev", - {0, BPF_PROG_TYPE_CGROUP_DEVICE, 0}, + {0, BPF_PROG_TYPE_CGROUP_DEVICE, BPF_CGROUP_DEVICE}, {0, BPF_CGROUP_DEVICE}, }, - {"sockops", {0, BPF_PROG_TYPE_SOCK_OPS, 0}, {0, BPF_CGROUP_SOCK_OPS} }, + { + "sockops", + {0, BPF_PROG_TYPE_SOCK_OPS, BPF_CGROUP_SOCK_OPS}, + {0, BPF_CGROUP_SOCK_OPS}, + }, { "sk_skb/stream_parser", - {0, BPF_PROG_TYPE_SK_SKB, 0}, + {0, BPF_PROG_TYPE_SK_SKB, BPF_SK_SKB_STREAM_PARSER}, {0, BPF_SK_SKB_STREAM_PARSER}, }, { "sk_skb/stream_verdict", - {0, BPF_PROG_TYPE_SK_SKB, 0}, + {0, BPF_PROG_TYPE_SK_SKB, BPF_SK_SKB_STREAM_VERDICT}, {0, BPF_SK_SKB_STREAM_VERDICT}, }, {"sk_skb", {0, BPF_PROG_TYPE_SK_SKB, 0}, {-EINVAL, 0} }, - {"sk_msg", {0, BPF_PROG_TYPE_SK_MSG, 0}, {0, BPF_SK_MSG_VERDICT} }, - {"lirc_mode2", {0, BPF_PROG_TYPE_LIRC_MODE2, 0}, {0, BPF_LIRC_MODE2} }, + { + "sk_msg", + {0, BPF_PROG_TYPE_SK_MSG, BPF_SK_MSG_VERDICT}, + {0, BPF_SK_MSG_VERDICT}, + }, + { + "lirc_mode2", + {0, BPF_PROG_TYPE_LIRC_MODE2, BPF_LIRC_MODE2}, + {0, BPF_LIRC_MODE2}, + }, { "flow_dissector", - {0, BPF_PROG_TYPE_FLOW_DISSECTOR, 0}, + {0, BPF_PROG_TYPE_FLOW_DISSECTOR, BPF_FLOW_DISSECTOR}, {0, BPF_FLOW_DISSECTOR}, }, { @@ -158,17 +170,17 @@ static void test_prog_type_by_name(const struct sec_name_test *test) &expected_attach_type); CHECK(rc != test->expected_load.rc, "check_code", - "prog: unexpected rc=%d for %s", rc, test->sec_name); + "prog: unexpected rc=%d for %s\n", rc, test->sec_name); if (rc) return; CHECK(prog_type != test->expected_load.prog_type, "check_prog_type", - "prog: unexpected prog_type=%d for %s", + "prog: unexpected prog_type=%d for %s\n", prog_type, test->sec_name); CHECK(expected_attach_type != test->expected_load.expected_attach_type, - "check_attach_type", "prog: unexpected expected_attach_type=%d for %s", + "check_attach_type", "prog: unexpected expected_attach_type=%d for %s\n", expected_attach_type, test->sec_name); } @@ -180,13 +192,13 @@ static void test_attach_type_by_name(const struct sec_name_test *test) rc = libbpf_attach_type_by_name(test->sec_name, &attach_type); CHECK(rc != test->expected_attach.rc, "check_ret", - "attach: unexpected rc=%d for %s", rc, test->sec_name); + "attach: unexpected rc=%d for %s\n", rc, test->sec_name); if (rc) return; CHECK(attach_type != test->expected_attach.attach_type, - "check_attach_type", "attach: unexpected attach_type=%d for %s", + "check_attach_type", "attach: unexpected attach_type=%d for %s\n", attach_type, test->sec_name); } |