diff options
| -rw-r--r-- | kernel/bpf/btf.c | 205 |
1 files changed, 205 insertions, 0 deletions
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 18bf266ceeda..4e31249f6c61 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -250,6 +250,10 @@ struct btf_kind_operations { u32 meta_left); int (*resolve)(struct btf_verifier_env *env, const struct resolve_vertex *v); + int (*check_member)(struct btf_verifier_env *env, + const struct btf_type *struct_type, + const struct btf_member *member, + const struct btf_type *member_type); void (*log_details)(struct btf_verifier_env *env, const struct btf_type *t); }; @@ -760,6 +764,16 @@ const struct btf_type *btf_type_id_size(const struct btf *btf, return size_type; } +static int btf_df_check_member(struct btf_verifier_env *env, + const struct btf_type *struct_type, + const struct btf_member *member, + const struct btf_type *member_type) +{ + btf_verifier_log_basic(env, struct_type, + "Unsupported check_member"); + return -EINVAL; +} + static int btf_df_resolve(struct btf_verifier_env *env, const struct resolve_vertex *v) { @@ -767,6 +781,44 @@ static int btf_df_resolve(struct btf_verifier_env *env, return -EINVAL; } +static int btf_int_check_member(struct btf_verifier_env *env, + const struct btf_type *struct_type, + const struct btf_member *member, + const struct btf_type *member_type) +{ + u32 int_data = btf_type_int(member_type); + u32 struct_bits_off = member->offset; + u32 struct_size = struct_type->size; + u32 nr_copy_bits; + u32 bytes_offset; + + if (U32_MAX - struct_bits_off < BTF_INT_OFFSET(int_data)) { + btf_verifier_log_member(env, struct_type, member, + "bits_offset exceeds U32_MAX"); + return -EINVAL; + } + + struct_bits_off += BTF_INT_OFFSET(int_data); + bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off); + nr_copy_bits = BTF_INT_BITS(int_data) + + BITS_PER_BYTE_MASKED(struct_bits_off); + + if (nr_copy_bits > BITS_PER_U64) { + btf_verifier_log_member(env, struct_type, member, + "nr_copy_bits exceeds 64"); + return -EINVAL; + } + + if (struct_size < bytes_offset || + struct_size - bytes_offset < BITS_ROUNDUP_BYTES(nr_copy_bits)) { + btf_verifier_log_member(env, struct_type, member, + "Member exceeds struct_size"); + return -EINVAL; + } + + return 0; +} + static s32 btf_int_check_meta(struct btf_verifier_env *env, const struct btf_type *t, u32 meta_left) @@ -830,9 +882,61 @@ static void btf_int_log(struct btf_verifier_env *env, static const struct btf_kind_operations int_ops = { .check_meta = btf_int_check_meta, .resolve = btf_df_resolve, + .check_member = btf_int_check_member, .log_details = btf_int_log, }; +static int btf_modifier_check_member(struct btf_verifier_env *env, + const struct btf_type *struct_type, + const struct btf_member *member, + const struct btf_type *member_type) +{ + const struct btf_type *resolved_type; + u32 resolved_type_id = member->type; + struct btf_member resolved_member; + struct btf *btf = env->btf; + + resolved_type = btf_type_id_size(btf, &resolved_type_id, NULL); + if (!resolved_type) { + btf_verifier_log_member(env, struct_type, member, + "Invalid member"); + return -EINVAL; + } + + resolved_member = *member; + resolved_member.type = resolved_type_id; + + return btf_type_ops(resolved_type)->check_member(env, struct_type, + &resolved_member, + resolved_type); +} + +static int btf_ptr_check_member(struct btf_verifier_env *env, + const struct btf_type *struct_type, + const struct btf_member *member, + const struct btf_type *member_type) +{ + u32 struct_size, struct_bits_off, bytes_offset; + + struct_size = struct_type->size; + struct_bits_off = member->offset; + bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off); + + if (BITS_PER_BYTE_MASKED(struct_bits_off)) { + btf_verifier_log_member(env, struct_type, member, + "Member is not byte aligned"); + return -EINVAL; + } + + if (struct_size - bytes_offset < sizeof(void *)) { + btf_verifier_log_member(env, struct_type, member, + "Member exceeds struct_size"); + return -EINVAL; + } + + return 0; +} + static int btf_ref_type_check_meta(struct btf_verifier_env *env, const struct btf_type *t, u32 meta_left) @@ -959,21 +1063,53 @@ static void btf_ref_type_log(struct btf_verifier_env *env, static struct btf_kind_operations modifier_ops = { .check_meta = btf_ref_type_check_meta, .resolve = btf_modifier_resolve, + .check_member = btf_modifier_check_member, .log_details = btf_ref_type_log, }; static struct btf_kind_operations ptr_ops = { .check_meta = btf_ref_type_check_meta, .resolve = btf_ptr_resolve, + .check_member = btf_ptr_check_member, .log_details = btf_ref_type_log, }; static struct btf_kind_operations fwd_ops = { .check_meta = btf_ref_type_check_meta, .resolve = btf_df_resolve, + .check_member = btf_df_check_member, .log_details = btf_ref_type_log, }; +static int btf_array_check_member(struct btf_verifier_env *env, + const struct btf_type *struct_type, + const struct btf_member *member, + const struct btf_type *member_type) +{ + u32 struct_bits_off = member->offset; + u32 struct_size, bytes_offset; + u32 array_type_id, array_size; + struct btf *btf = env->btf; + + if (BITS_PER_BYTE_MASKED(struct_bits_off)) { + btf_verifier_log_member(env, struct_type, member, + "Member is not byte aligned"); + return -EINVAL; + } + + array_type_id = member->type; + btf_type_id_size(btf, &array_type_id, &array_size); + struct_size = struct_type->size; + bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off); + if (struct_size - bytes_offset < array_size) { + btf_verifier_log_member(env, struct_type, member, + "Member exceeds struct_size"); + return -EINVAL; + } + + return 0; +} + static s32 btf_array_check_meta(struct btf_verifier_env *env, const struct btf_type *t, u32 meta_left) @@ -1076,9 +1212,35 @@ static void btf_array_log(struct btf_verifier_env *env, static struct btf_kind_operations array_ops = { .check_meta = btf_array_check_meta, .resolve = btf_array_resolve, + .check_member = btf_array_check_member, .log_details = btf_array_log, }; +static int btf_struct_check_member(struct btf_verifier_env *env, + const struct btf_type *struct_type, + const struct btf_member *member, + const struct btf_type *member_type) +{ + u32 struct_bits_off = member->offset; + u32 struct_size, bytes_offset; + + if (BITS_PER_BYTE_MASKED(struct_bits_off)) { + btf_verifier_log_member(env, struct_type, member, + "Member is not byte aligned"); + return -EINVAL; + } + + struct_size = struct_type->size; + bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off); + if (struct_size - bytes_offset < member_type->size) { + btf_verifier_log_member(env, struct_type, member, + "Member exceeds struct_size"); + return -EINVAL; + } + + return 0; +} + static s32 btf_struct_check_meta(struct btf_verifier_env *env, const struct btf_type *t, u32 meta_left) @@ -1137,6 +1299,7 @@ static int btf_struct_resolve(struct btf_verifier_env *env, const struct resolve_vertex *v) { const struct btf_member *member; + int err; u16 i; /* Before continue resolving the next_member, @@ -1144,6 +1307,7 @@ static int btf_struct_resolve(struct btf_verifier_env *env, * type with size info. */ if (v->next_member) { + const struct btf_type *last_member_type; const struct btf_member *last_member; u16 last_member_type_id; @@ -1152,6 +1316,14 @@ static int btf_struct_resolve(struct btf_verifier_env *env, if (WARN_ON_ONCE(!env_type_is_resolved(env, last_member_type_id))) return -EINVAL; + + last_member_type = btf_type_by_id(env->btf, + last_member_type_id); + err = btf_type_ops(last_member_type)->check_member(env, v->t, + last_member, + last_member_type); + if (err) + return err; } for_each_member_from(i, v->next_member, v->t, member) { @@ -1170,6 +1342,12 @@ static int btf_struct_resolve(struct btf_verifier_env *env, env_stack_set_next_member(env, i + 1); return env_stack_push(env, member_type, member_type_id); } + + err = btf_type_ops(member_type)->check_member(env, v->t, + member, + member_type); + if (err) + return err; } env_stack_pop_resolved(env, 0, 0); @@ -1186,9 +1364,35 @@ static void btf_struct_log(struct btf_verifier_env *env, static struct btf_kind_operations struct_ops = { .check_meta = btf_struct_check_meta, .resolve = btf_struct_resolve, + .check_member = btf_struct_check_member, .log_details = btf_struct_log, }; +static int btf_enum_check_member(struct btf_verifier_env *env, + const struct btf_type *struct_type, + const struct btf_member *member, + const struct btf_type *member_type) +{ + u32 struct_bits_off = member->offset; + u32 struct_size, bytes_offset; + + if (BITS_PER_BYTE_MASKED(struct_bits_off)) { + btf_verifier_log_member(env, struct_type, member, + "Member is not byte aligned"); + return -EINVAL; + } + + struct_size = struct_type->size; + bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off); + if (struct_size - bytes_offset < sizeof(int)) { + btf_verifier_log_member(env, struct_type, member, + "Member exceeds struct_size"); + return -EINVAL; + } + + return 0; +} + static s32 btf_enum_check_meta(struct btf_verifier_env *env, const struct btf_type *t, u32 meta_left) @@ -1240,6 +1444,7 @@ static void btf_enum_log(struct btf_verifier_env *env, static struct btf_kind_operations enum_ops = { .check_meta = btf_enum_check_meta, .resolve = btf_df_resolve, + .check_member = btf_enum_check_member, .log_details = btf_enum_log, }; |