diff options
| -rw-r--r-- | kernel/bpf/btf.c | 80 |
1 files changed, 56 insertions, 24 deletions
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 75da6cbae47d..e388a6598de2 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -443,6 +443,28 @@ static const struct btf_type *btf_type_by_id(const struct btf *btf, u32 type_id) return btf->types[type_id]; } +/* + * Regular int is not a bit field and it must be either + * u8/u16/u32/u64. + */ +static bool btf_type_int_is_regular(const struct btf_type *t) +{ + u16 nr_bits, nr_bytes; + u32 int_data; + + int_data = btf_type_int(t); + nr_bits = BTF_INT_BITS(int_data); + nr_bytes = BITS_ROUNDUP_BYTES(nr_bits); + if (BITS_PER_BYTE_MASKED(nr_bits) || + BTF_INT_OFFSET(int_data) || + (nr_bytes != sizeof(u8) && nr_bytes != sizeof(u16) && + nr_bytes != sizeof(u32) && nr_bytes != sizeof(u64))) { + return false; + } + + return true; +} + __printf(2, 3) static void __btf_verifier_log(struct bpf_verifier_log *log, const char *fmt, ...) { @@ -1308,14 +1330,16 @@ static s32 btf_array_check_meta(struct btf_verifier_env *env, return -EINVAL; } - /* We are a little forgiving on array->index_type since - * the kernel is not using it. - */ - /* Array elem cannot be in type void, - * so !array->type is not allowed. + /* Array elem type and index type cannot be in type void, + * so !array->type and !array->index_type are not allowed. */ if (!array->type || BTF_TYPE_PARENT(array->type)) { - btf_verifier_log_type(env, t, "Invalid type_id"); + btf_verifier_log_type(env, t, "Invalid elem"); + return -EINVAL; + } + + if (!array->index_type || BTF_TYPE_PARENT(array->index_type)) { + btf_verifier_log_type(env, t, "Invalid index"); return -EINVAL; } @@ -1328,11 +1352,32 @@ static int btf_array_resolve(struct btf_verifier_env *env, const struct resolve_vertex *v) { const struct btf_array *array = btf_type_array(v->t); - const struct btf_type *elem_type; - u32 elem_type_id = array->type; + const struct btf_type *elem_type, *index_type; + u32 elem_type_id, index_type_id; struct btf *btf = env->btf; u32 elem_size; + /* Check array->index_type */ + index_type_id = array->index_type; + index_type = btf_type_by_id(btf, index_type_id); + if (btf_type_is_void_or_null(index_type)) { + btf_verifier_log_type(env, v->t, "Invalid index"); + return -EINVAL; + } + + if (!env_type_is_resolve_sink(env, index_type) && + !env_type_is_resolved(env, index_type_id)) + return env_stack_push(env, index_type, index_type_id); + + index_type = btf_type_id_size(btf, &index_type_id, NULL); + if (!index_type || !btf_type_is_int(index_type) || + !btf_type_int_is_regular(index_type)) { + btf_verifier_log_type(env, v->t, "Invalid index"); + return -EINVAL; + } + + /* Check array->type */ + elem_type_id = array->type; elem_type = btf_type_by_id(btf, elem_type_id); if (btf_type_is_void_or_null(elem_type)) { btf_verifier_log_type(env, v->t, @@ -1350,22 +1395,9 @@ static int btf_array_resolve(struct btf_verifier_env *env, return -EINVAL; } - if (btf_type_is_int(elem_type)) { - int int_type_data = btf_type_int(elem_type); - u16 nr_bits = BTF_INT_BITS(int_type_data); - u16 nr_bytes = BITS_ROUNDUP_BYTES(nr_bits); - - /* Put more restriction on array of int. The int cannot - * be a bit field and it must be either u8/u16/u32/u64. - */ - if (BITS_PER_BYTE_MASKED(nr_bits) || - BTF_INT_OFFSET(int_type_data) || - (nr_bytes != sizeof(u8) && nr_bytes != sizeof(u16) && - nr_bytes != sizeof(u32) && nr_bytes != sizeof(u64))) { - btf_verifier_log_type(env, v->t, - "Invalid array of int"); - return -EINVAL; - } + if (btf_type_is_int(elem_type) && !btf_type_int_is_regular(elem_type)) { + btf_verifier_log_type(env, v->t, "Invalid array of int"); + return -EINVAL; } if (array->nelems && elem_size > U32_MAX / array->nelems) { |