From 8175383f2320dbc1b4e803d857ed499ed3e76199 Mon Sep 17 00:00:00 2001 From: Martin KaFai Lau Date: Sat, 2 Jun 2018 09:06:51 -0700 Subject: bpf: btf: Ensure t->type == 0 for BTF_KIND_FWD The t->type in BTF_KIND_FWD is not used. It must be 0. This patch ensures that and also adds a test case in test_btf.c Signed-off-by: Martin KaFai Lau Signed-off-by: Alexei Starovoitov --- kernel/bpf/btf.c | 21 ++++++++++++++++++++- tools/testing/selftests/bpf/test_btf.c | 22 ++++++++++++++++++++++ 2 files changed, 42 insertions(+), 1 deletion(-) diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 84ad532f2854..8653ab004c73 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -1286,8 +1286,27 @@ static struct btf_kind_operations ptr_ops = { .seq_show = btf_ptr_seq_show, }; +static s32 btf_fwd_check_meta(struct btf_verifier_env *env, + const struct btf_type *t, + u32 meta_left) +{ + if (btf_type_vlen(t)) { + btf_verifier_log_type(env, t, "vlen != 0"); + return -EINVAL; + } + + if (t->type) { + btf_verifier_log_type(env, t, "type != 0"); + return -EINVAL; + } + + btf_verifier_log_type(env, t, NULL); + + return 0; +} + static struct btf_kind_operations fwd_ops = { - .check_meta = btf_ref_type_check_meta, + .check_meta = btf_fwd_check_meta, .resolve = btf_df_resolve, .check_member = btf_df_check_member, .log_details = btf_ref_type_log, diff --git a/tools/testing/selftests/bpf/test_btf.c b/tools/testing/selftests/bpf/test_btf.c index fd8246e84149..3619f3023088 100644 --- a/tools/testing/selftests/bpf/test_btf.c +++ b/tools/testing/selftests/bpf/test_btf.c @@ -1242,6 +1242,28 @@ static struct btf_raw_test raw_tests[] = { .err_str = "Invalid btf_info", }, +{ + .descr = "fwd test. t->type != 0\"", + .raw_types = { + /* int */ /* [1] */ + BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), + /* fwd type */ /* [2] */ + BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_FWD, 0, 0), 1), + BTF_END_RAW, + }, + .str_sec = "", + .str_sec_size = sizeof(""), + .map_type = BPF_MAP_TYPE_ARRAY, + .map_name = "fwd_test_map", + .key_size = sizeof(int), + .value_size = sizeof(int), + .key_type_id = 1, + .value_type_id = 1, + .max_entries = 4, + .btf_load_err = true, + .err_str = "type != 0", +}, + }; /* struct btf_raw_test raw_tests[] */ static const char *get_next_str(const char *start, const char *end) -- cgit v1.2.3-59-g8ed1b