From d86630a69e256d449e77298d6e9df8ef2fc8ff99 Mon Sep 17 00:00:00 2001 From: Lorenz Bauer Date: Wed, 23 Sep 2020 17:01:55 +0100 Subject: [PATCH] UPSTREAM: bpf: Explicitly size compatible_reg_types Arrays with designated initializers have an implicit length of the highest initialized value plus one. I used this to ensure that newly added entries in enum bpf_reg_type get a NULL entry in compatible_reg_types. This is difficult to understand since it requires knowledge of the peculiarities of designated initializers. Use __BPF_ARG_TYPE_MAX to size the array instead. Suggested-by: Alexei Starovoitov Change-Id: I7a84c1f74e216603affa192650f55ae91a65ca86 Signed-off-by: Lorenz Bauer Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20200923160156.80814-1-lmb@cloudflare.com --- kernel/bpf/verifier.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 06dc46b229bf..69286f80f378 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -4000,7 +4000,7 @@ static const struct bpf_reg_types const_map_ptr_types = { .types = { CONST_PTR_T static const struct bpf_reg_types btf_ptr_types = { .types = { PTR_TO_BTF_ID } }; static const struct bpf_reg_types spin_lock_types = { .types = { PTR_TO_MAP_VALUE } }; -static const struct bpf_reg_types *compatible_reg_types[] = { +static const struct bpf_reg_types *compatible_reg_types[__BPF_ARG_TYPE_MAX] = { [ARG_PTR_TO_MAP_KEY] = &map_key_value_types, [ARG_PTR_TO_MAP_VALUE] = &map_key_value_types, [ARG_PTR_TO_UNINIT_MAP_VALUE] = &map_key_value_types, @@ -4023,7 +4023,6 @@ static const struct bpf_reg_types *compatible_reg_types[] = { [ARG_PTR_TO_ALLOC_MEM_OR_NULL] = &alloc_mem_types, [ARG_PTR_TO_INT] = &int_ptr_types, [ARG_PTR_TO_LONG] = &int_ptr_types, - [__BPF_ARG_TYPE_MAX] = NULL, }; static int check_reg_type(struct bpf_verifier_env *env, u32 regno,