diff options
Diffstat (limited to 'tools/testing/selftests/bpf/prog_tests/token.c')
| -rw-r--r-- | tools/testing/selftests/bpf/prog_tests/token.c | 182 |
1 files changed, 161 insertions, 21 deletions
diff --git a/tools/testing/selftests/bpf/prog_tests/token.c b/tools/testing/selftests/bpf/prog_tests/token.c index c3ab9b6fb069..b81dde283052 100644 --- a/tools/testing/selftests/bpf/prog_tests/token.c +++ b/tools/testing/selftests/bpf/prog_tests/token.c @@ -19,6 +19,7 @@ #include "priv_prog.skel.h" #include "dummy_st_ops_success.skel.h" #include "token_lsm.skel.h" +#include "priv_freplace_prog.skel.h" static inline int sys_mount(const char *dev_name, const char *dir_name, const char *type, unsigned long flags, @@ -114,7 +115,7 @@ static int create_bpffs_fd(void) static int materialize_bpffs_fd(int fs_fd, struct bpffs_opts *opts) { - int mnt_fd, err; + int err; /* set up token delegation mount options */ err = set_delegate_mask(fs_fd, "delegate_cmds", opts->cmds, opts->cmds_str); @@ -135,12 +136,7 @@ static int materialize_bpffs_fd(int fs_fd, struct bpffs_opts *opts) if (err < 0) return -errno; - /* create O_PATH fd for detached mount */ - mnt_fd = sys_fsmount(fs_fd, 0, 0); - if (err < 0) - return -errno; - - return mnt_fd; + return 0; } /* send FD over Unix domain (AF_UNIX) socket */ @@ -286,6 +282,7 @@ static void child(int sock_fd, struct bpffs_opts *opts, child_callback_fn callba { int mnt_fd = -1, fs_fd = -1, err = 0, bpffs_fd = -1, token_fd = -1; struct token_lsm *lsm_skel = NULL; + char one; /* load and attach LSM "policy" before we go into unpriv userns */ lsm_skel = token_lsm__open_and_load(); @@ -332,13 +329,19 @@ static void child(int sock_fd, struct bpffs_opts *opts, child_callback_fn callba err = sendfd(sock_fd, fs_fd); if (!ASSERT_OK(err, "send_fs_fd")) goto cleanup; - zclose(fs_fd); + + /* wait that the parent reads the fd, does the fsconfig() calls + * and send us a signal that it is done + */ + err = read(sock_fd, &one, sizeof(one)); + if (!ASSERT_GE(err, 0, "read_one")) + goto cleanup; /* avoid mucking around with mount namespaces and mounting at - * well-known path, just get detach-mounted BPF FS fd back from parent + * well-known path, just create O_PATH fd for detached mount */ - err = recvfd(sock_fd, &mnt_fd); - if (!ASSERT_OK(err, "recv_mnt_fd")) + mnt_fd = sys_fsmount(fs_fd, 0, 0); + if (!ASSERT_OK_FD(mnt_fd, "mnt_fd")) goto cleanup; /* try to fspick() BPF FS and try to add some delegation options */ @@ -428,24 +431,24 @@ again: static void parent(int child_pid, struct bpffs_opts *bpffs_opts, int sock_fd) { - int fs_fd = -1, mnt_fd = -1, token_fd = -1, err; + int fs_fd = -1, token_fd = -1, err; + char one = 1; err = recvfd(sock_fd, &fs_fd); if (!ASSERT_OK(err, "recv_bpffs_fd")) goto cleanup; - mnt_fd = materialize_bpffs_fd(fs_fd, bpffs_opts); - if (!ASSERT_GE(mnt_fd, 0, "materialize_bpffs_fd")) { + err = materialize_bpffs_fd(fs_fd, bpffs_opts); + if (!ASSERT_GE(err, 0, "materialize_bpffs_fd")) { err = -EINVAL; goto cleanup; } - zclose(fs_fd); - /* pass BPF FS context object to parent */ - err = sendfd(sock_fd, mnt_fd); - if (!ASSERT_OK(err, "send_mnt_fd")) + /* notify the child that we did the fsconfig() calls and it can proceed. */ + err = write(sock_fd, &one, sizeof(one)); + if (!ASSERT_EQ(err, sizeof(one), "send_one")) goto cleanup; - zclose(mnt_fd); + zclose(fs_fd); /* receive BPF token FD back from child for some extra tests */ err = recvfd(sock_fd, &token_fd); @@ -458,7 +461,6 @@ static void parent(int child_pid, struct bpffs_opts *bpffs_opts, int sock_fd) cleanup: zclose(sock_fd); zclose(fs_fd); - zclose(mnt_fd); zclose(token_fd); if (child_pid > 0) @@ -788,6 +790,84 @@ static int userns_obj_priv_prog(int mnt_fd, struct token_lsm *lsm_skel) return 0; } +static int userns_obj_priv_freplace_setup(int mnt_fd, struct priv_freplace_prog **fr_skel, + struct priv_prog **skel, int *tgt_fd) +{ + LIBBPF_OPTS(bpf_object_open_opts, opts); + int err; + char buf[256]; + + /* 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, "priv_prog__open_opts")) + return -EINVAL; + err = priv_prog__load(*skel); + if (!ASSERT_OK(err, "priv_prog__load")) + return -EINVAL; + + *fr_skel = priv_freplace_prog__open_opts(&opts); + if (!ASSERT_OK_PTR(*skel, "priv_freplace_prog__open_opts")) + return -EINVAL; + + *tgt_fd = bpf_program__fd((*skel)->progs.xdp_prog1); + return 0; +} + +/* Verify that freplace works from user namespace, because bpf token is loaded + * in bpf_object__prepare + */ +static int userns_obj_priv_freplace_prog(int mnt_fd, struct token_lsm *lsm_skel) +{ + struct priv_freplace_prog *fr_skel = NULL; + struct priv_prog *skel = NULL; + int err, tgt_fd; + + err = userns_obj_priv_freplace_setup(mnt_fd, &fr_skel, &skel, &tgt_fd); + if (!ASSERT_OK(err, "setup")) + goto out; + + err = bpf_object__prepare(fr_skel->obj); + if (!ASSERT_OK(err, "freplace__prepare")) + goto out; + + err = bpf_program__set_attach_target(fr_skel->progs.new_xdp_prog2, tgt_fd, "xdp_prog1"); + if (!ASSERT_OK(err, "set_attach_target")) + goto out; + + err = priv_freplace_prog__load(fr_skel); + ASSERT_OK(err, "priv_freplace_prog__load"); + +out: + priv_freplace_prog__destroy(fr_skel); + priv_prog__destroy(skel); + return err; +} + +/* Verify that replace fails to set attach target from user namespace without bpf token */ +static int userns_obj_priv_freplace_prog_fail(int mnt_fd, struct token_lsm *lsm_skel) +{ + struct priv_freplace_prog *fr_skel = NULL; + struct priv_prog *skel = NULL; + int err, tgt_fd; + + err = userns_obj_priv_freplace_setup(mnt_fd, &fr_skel, &skel, &tgt_fd); + if (!ASSERT_OK(err, "setup")) + goto out; + + err = bpf_program__set_attach_target(fr_skel->progs.new_xdp_prog2, tgt_fd, "xdp_prog1"); + if (ASSERT_ERR(err, "attach fails")) + err = 0; + else + err = -EINVAL; + +out: + priv_freplace_prog__destroy(fr_skel); + priv_prog__destroy(skel); + return err; +} + /* 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 @@ -967,6 +1047,41 @@ err_out: #define bit(n) (1ULL << (n)) +static int userns_bpf_token_info(int mnt_fd, struct token_lsm *lsm_skel) +{ + int err, token_fd = -1; + struct bpf_token_info info; + u32 len = sizeof(struct bpf_token_info); + + /* create BPF token from BPF FS mount */ + token_fd = bpf_token_create(mnt_fd, NULL); + if (!ASSERT_GT(token_fd, 0, "token_create")) { + err = -EINVAL; + goto cleanup; + } + + memset(&info, 0, len); + err = bpf_obj_get_info_by_fd(token_fd, &info, &len); + if (!ASSERT_ERR(err, "bpf_obj_get_token_info")) + goto cleanup; + if (!ASSERT_EQ(info.allowed_cmds, bit(BPF_MAP_CREATE), "token_info_cmds_map_create")) { + err = -EINVAL; + goto cleanup; + } + if (!ASSERT_EQ(info.allowed_progs, bit(BPF_PROG_TYPE_XDP), "token_info_progs_xdp")) { + err = -EINVAL; + goto cleanup; + } + + /* The BPF_PROG_TYPE_EXT is not set in token */ + if (ASSERT_EQ(info.allowed_progs, bit(BPF_PROG_TYPE_EXT), "token_info_progs_ext")) + err = -EINVAL; + +cleanup: + zclose(token_fd); + return err; +} + void test_token(void) { if (test__start_subtest("map_token")) { @@ -1004,12 +1119,28 @@ void test_token(void) if (test__start_subtest("obj_priv_prog")) { struct bpffs_opts opts = { .cmds = bit(BPF_PROG_LOAD), - .progs = bit(BPF_PROG_TYPE_KPROBE), + .progs = bit(BPF_PROG_TYPE_XDP), .attachs = ~0ULL, }; subtest_userns(&opts, userns_obj_priv_prog); } + if (test__start_subtest("obj_priv_freplace_prog")) { + struct bpffs_opts opts = { + .cmds = bit(BPF_BTF_LOAD) | bit(BPF_PROG_LOAD) | bit(BPF_BTF_GET_FD_BY_ID), + .progs = bit(BPF_PROG_TYPE_EXT) | bit(BPF_PROG_TYPE_XDP), + .attachs = ~0ULL, + }; + subtest_userns(&opts, userns_obj_priv_freplace_prog); + } + if (test__start_subtest("obj_priv_freplace_prog_fail")) { + struct bpffs_opts opts = { + .cmds = bit(BPF_BTF_LOAD) | bit(BPF_PROG_LOAD) | bit(BPF_BTF_GET_FD_BY_ID), + .progs = bit(BPF_PROG_TYPE_EXT) | bit(BPF_PROG_TYPE_XDP), + .attachs = ~0ULL, + }; + subtest_userns(&opts, userns_obj_priv_freplace_prog_fail); + } if (test__start_subtest("obj_priv_btf_fail")) { struct bpffs_opts opts = { /* disallow BTF loading */ @@ -1054,4 +1185,13 @@ void test_token(void) subtest_userns(&opts, userns_obj_priv_implicit_token_envvar); } + if (test__start_subtest("bpf_token_info")) { + struct bpffs_opts opts = { + .cmds = bit(BPF_MAP_CREATE), + .progs = bit(BPF_PROG_TYPE_XDP), + .attachs = ~0ULL, + }; + + subtest_userns(&opts, userns_bpf_token_info); + } } |