Add a few tests that attempt to load BPF object containing privileged map, program, and the one requiring mandatory BTF uploading into the kernel (to validate token FD propagation to BPF_BTF_LOAD command). Signed-off-by: Andrii Nakryiko <andrii@xxxxxxxxxx> --- .../testing/selftests/bpf/prog_tests/token.c | 159 ++++++++++++++++++ tools/testing/selftests/bpf/progs/priv_map.c | 13 ++ tools/testing/selftests/bpf/progs/priv_prog.c | 13 ++ 3 files changed, 185 insertions(+) create mode 100644 tools/testing/selftests/bpf/progs/priv_map.c create mode 100644 tools/testing/selftests/bpf/progs/priv_prog.c diff --git a/tools/testing/selftests/bpf/prog_tests/token.c b/tools/testing/selftests/bpf/prog_tests/token.c index dc03790c6272..9812292336c9 100644 --- a/tools/testing/selftests/bpf/prog_tests/token.c +++ b/tools/testing/selftests/bpf/prog_tests/token.c @@ -14,6 +14,9 @@ #include <sys/socket.h> #include <sys/syscall.h> #include <sys/un.h> +#include "priv_map.skel.h" +#include "priv_prog.skel.h" +#include "dummy_st_ops_success.skel.h" static inline int sys_mount(const char *dev_name, const char *dir_name, const char *type, unsigned long flags, @@ -643,6 +646,123 @@ static int userns_prog_load(int mnt_fd) return err; } +static int userns_obj_priv_map(int mnt_fd) +{ + LIBBPF_OPTS(bpf_object_open_opts, opts); + char buf[256]; + struct priv_map *skel; + int err, token_fd; + + skel = priv_map__open_and_load(); + if (!ASSERT_ERR_PTR(skel, "obj_tokenless_load")) { + priv_map__destroy(skel); + return -EINVAL; + } + + /* use bpf_token_path to provide BPF FS path */ + snprintf(buf, sizeof(buf), "/proc/self/fd/%d", mnt_fd); + opts.bpf_token_path = buf; + skel = priv_map__open_opts(&opts); + if (!ASSERT_OK_PTR(skel, "obj_token_path_open")) + return -EINVAL; + + err = priv_map__load(skel); + priv_map__destroy(skel); + if (!ASSERT_OK(err, "obj_token_path_load")) + return -EINVAL; + + /* create token and pass it through bpf_token_fd */ + token_fd = bpf_token_create(mnt_fd, NULL); + if (!ASSERT_GT(token_fd, 0, "create_token")) + return -EINVAL; + + opts.bpf_token_path = NULL; + opts.bpf_token_fd = token_fd; + skel = priv_map__open_opts(&opts); + if (!ASSERT_OK_PTR(skel, "obj_token_fd_open")) + return -EINVAL; + + /* we can close our token FD, bpf_object owns dup()'ed FD now */ + close(token_fd); + + err = priv_map__load(skel); + priv_map__destroy(skel); + if (!ASSERT_OK(err, "obj_token_fd_load")) + return -EINVAL; + + return 0; +} + +static int userns_obj_priv_prog(int mnt_fd) +{ + LIBBPF_OPTS(bpf_object_open_opts, opts); + char buf[256]; + struct priv_prog *skel; + int err; + + skel = priv_prog__open_and_load(); + if (!ASSERT_ERR_PTR(skel, "obj_tokenless_load")) { + priv_prog__destroy(skel); + return -EINVAL; + } + + /* use bpf_token_path to provide BPF FS path */ + snprintf(buf, sizeof(buf), "/proc/self/fd/%d", mnt_fd); + opts.bpf_token_path = buf; + skel = priv_prog__open_opts(&opts); + if (!ASSERT_OK_PTR(skel, "obj_token_path_open")) + return -EINVAL; + + err = priv_prog__load(skel); + priv_prog__destroy(skel); + if (!ASSERT_OK(err, "obj_token_path_load")) + return -EINVAL; + + return 0; +} + +/* this test is called with BPF FS that doesn't delegate BPF_BTF_LOAD command, + * which should cause struct_ops application to fail, as BTF won't be uploaded + * into the kernel, even if STRUCT_OPS programs themselves are allowed + */ +static int validate_struct_ops_load(int mnt_fd, bool expect_success) +{ + LIBBPF_OPTS(bpf_object_open_opts, opts); + char buf[256]; + struct dummy_st_ops_success *skel; + int err; + + snprintf(buf, sizeof(buf), "/proc/self/fd/%d", mnt_fd); + opts.bpf_token_path = buf; + skel = dummy_st_ops_success__open_opts(&opts); + if (!ASSERT_OK_PTR(skel, "obj_token_path_open")) + return -EINVAL; + + err = dummy_st_ops_success__load(skel); + dummy_st_ops_success__destroy(skel); + if (expect_success) { + if (!ASSERT_OK(err, "obj_token_path_load")) + return -EINVAL; + } else /* expect failure */ { + if (!ASSERT_ERR(err, "obj_token_path_load")) + return -EINVAL; + } + + return 0; +} + +static int userns_obj_priv_btf_fail(int mnt_fd) +{ + return validate_struct_ops_load(mnt_fd, false /* should fail */); +} + +static int userns_obj_priv_btf_success(int mnt_fd) +{ + return validate_struct_ops_load(mnt_fd, true /* should succeed */); +} + +#define bit(n) (1ULL << (n)) + void test_token(void) { if (test__start_subtest("map_token")) { @@ -669,4 +789,43 @@ void test_token(void) subtest_userns(&opts, userns_prog_load); } + if (test__start_subtest("obj_priv_map")) { + struct bpffs_opts opts = { + .cmds = bit(BPF_MAP_CREATE), + .maps = bit(BPF_MAP_TYPE_QUEUE), + }; + + subtest_userns(&opts, userns_obj_priv_map); + } + if (test__start_subtest("obj_priv_prog")) { + struct bpffs_opts opts = { + .cmds = bit(BPF_PROG_LOAD), + .progs = bit(BPF_PROG_TYPE_KPROBE), + .attachs = ~0ULL, + }; + + subtest_userns(&opts, userns_obj_priv_prog); + } + if (test__start_subtest("obj_priv_btf_fail")) { + struct bpffs_opts opts = { + /* disallow BTF loading */ + .cmds = bit(BPF_MAP_CREATE) | bit(BPF_PROG_LOAD), + .maps = bit(BPF_MAP_TYPE_STRUCT_OPS), + .progs = bit(BPF_PROG_TYPE_STRUCT_OPS), + .attachs = ~0ULL, + }; + + subtest_userns(&opts, userns_obj_priv_btf_fail); + } + if (test__start_subtest("obj_priv_btf_success")) { + struct bpffs_opts opts = { + /* allow BTF loading */ + .cmds = bit(BPF_BTF_LOAD) | bit(BPF_MAP_CREATE) | bit(BPF_PROG_LOAD), + .maps = bit(BPF_MAP_TYPE_STRUCT_OPS), + .progs = bit(BPF_PROG_TYPE_STRUCT_OPS), + .attachs = ~0ULL, + }; + + subtest_userns(&opts, userns_obj_priv_btf_success); + } } diff --git a/tools/testing/selftests/bpf/progs/priv_map.c b/tools/testing/selftests/bpf/progs/priv_map.c new file mode 100644 index 000000000000..9085be50f03b --- /dev/null +++ b/tools/testing/selftests/bpf/progs/priv_map.c @@ -0,0 +1,13 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */ + +#include "vmlinux.h" +#include <bpf/bpf_helpers.h> + +char _license[] SEC("license") = "GPL"; + +struct { + __uint(type, BPF_MAP_TYPE_QUEUE); + __uint(max_entries, 1); + __type(value, __u32); +} priv_map SEC(".maps"); diff --git a/tools/testing/selftests/bpf/progs/priv_prog.c b/tools/testing/selftests/bpf/progs/priv_prog.c new file mode 100644 index 000000000000..3c7b2b618c8a --- /dev/null +++ b/tools/testing/selftests/bpf/progs/priv_prog.c @@ -0,0 +1,13 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */ + +#include "vmlinux.h" +#include <bpf/bpf_helpers.h> + +char _license[] SEC("license") = "GPL"; + +SEC("kprobe") +int kprobe_prog(void *ctx) +{ + return 1; +} -- 2.34.1