binder: fix decoding of vintf stability ParcelableHolder
Unlike the C++ implementation, `ParcelableHolder`s in rust are decoded
into a new object. The new object was losing the original stability
level, always reverting to local stability, so vintf parcelables would
fail the assertion.
We could replicate the C++ implementation, but it would require a lot of
API refactoring and it is easy to mess up. Instead, we make the
stability part of the type. This somewhat matches AIDL, where the
stability is a static annotation on the type containing the
`ParcelableHolder`.
Bug: 366383257
Test: m
Change-Id: Ic4654830d404fbf18046660eeb0129ab8abf7e61
diff --git a/libs/binder/rust/src/binder.rs b/libs/binder/rust/src/binder.rs
index 9a252b8..23026e5 100644
--- a/libs/binder/rust/src/binder.rs
+++ b/libs/binder/rust/src/binder.rs
@@ -136,6 +136,31 @@
}
}
+/// Same as `Stability`, but in the form of a trait. Used when the stability should be encoded in
+/// the type.
+///
+/// When/if the `adt_const_params` Rust feature is stabilized, this could be replace by using
+/// `Stability` directly with const generics.
+pub trait StabilityType {
+ /// The `Stability` represented by this type.
+ const VALUE: Stability;
+}
+
+/// `Stability::Local`.
+#[derive(Debug)]
+pub enum LocalStabilityType {}
+/// `Stability::Vintf`.
+#[derive(Debug)]
+pub enum VintfStabilityType {}
+
+impl StabilityType for LocalStabilityType {
+ const VALUE: Stability = Stability::Local;
+}
+
+impl StabilityType for VintfStabilityType {
+ const VALUE: Stability = Stability::Vintf;
+}
+
/// A local service that can be remotable via Binder.
///
/// An object that implement this interface made be made into a Binder service
diff --git a/libs/binder/rust/src/lib.rs b/libs/binder/rust/src/lib.rs
index e70f4f0..e048696 100644
--- a/libs/binder/rust/src/lib.rs
+++ b/libs/binder/rust/src/lib.rs
@@ -128,9 +128,10 @@
/// without AIDL.
pub mod binder_impl {
pub use crate::binder::{
- IBinderInternal, InterfaceClass, Remotable, Stability, ToAsyncInterface, ToSyncInterface,
- TransactionCode, TransactionFlags, FIRST_CALL_TRANSACTION, FLAG_CLEAR_BUF, FLAG_ONEWAY,
- FLAG_PRIVATE_LOCAL, LAST_CALL_TRANSACTION,
+ IBinderInternal, InterfaceClass, LocalStabilityType, Remotable, Stability, StabilityType,
+ ToAsyncInterface, ToSyncInterface, TransactionCode, TransactionFlags, VintfStabilityType,
+ FIRST_CALL_TRANSACTION, FLAG_CLEAR_BUF, FLAG_ONEWAY, FLAG_PRIVATE_LOCAL,
+ LAST_CALL_TRANSACTION,
};
pub use crate::binder_async::BinderAsyncRuntime;
pub use crate::error::status_t;
diff --git a/libs/binder/rust/src/parcel/parcelable_holder.rs b/libs/binder/rust/src/parcel/parcelable_holder.rs
index f906113..87b42ab 100644
--- a/libs/binder/rust/src/parcel/parcelable_holder.rs
+++ b/libs/binder/rust/src/parcel/parcelable_holder.rs
@@ -15,6 +15,7 @@
*/
use crate::binder::Stability;
+use crate::binder::StabilityType;
use crate::error::StatusCode;
use crate::parcel::{
BorrowedParcel, Deserialize, Parcel, Parcelable, Serialize, NON_NULL_PARCELABLE_FLAG,
@@ -60,7 +61,7 @@
/// `Send` nor `Sync`), mainly because it internally contains
/// a `Parcel` which in turn is not thread-safe.
#[derive(Debug)]
-pub struct ParcelableHolder {
+pub struct ParcelableHolder<STABILITY: StabilityType> {
// This is a `Mutex` because of `get_parcelable`
// which takes `&self` for consistency with C++.
// We could make `get_parcelable` take a `&mut self`
@@ -68,13 +69,17 @@
// improvement, but then callers would require a mutable
// `ParcelableHolder` even for that getter method.
data: Mutex<ParcelableHolderData>,
- stability: Stability,
+
+ _stability_phantom: std::marker::PhantomData<STABILITY>,
}
-impl ParcelableHolder {
+impl<STABILITY: StabilityType> ParcelableHolder<STABILITY> {
/// Construct a new `ParcelableHolder` with the given stability.
- pub fn new(stability: Stability) -> Self {
- Self { data: Mutex::new(ParcelableHolderData::Empty), stability }
+ pub fn new() -> Self {
+ Self {
+ data: Mutex::new(ParcelableHolderData::Empty),
+ _stability_phantom: Default::default(),
+ }
}
/// Reset the contents of this `ParcelableHolder`.
@@ -91,7 +96,7 @@
where
T: Any + Parcelable + ParcelableMetadata + std::fmt::Debug + Send + Sync,
{
- if self.stability > p.get_stability() {
+ if STABILITY::VALUE > p.get_stability() {
return Err(StatusCode::BAD_VALUE);
}
@@ -157,30 +162,36 @@
/// Return the stability value of this object.
pub fn get_stability(&self) -> Stability {
- self.stability
+ STABILITY::VALUE
}
}
-impl Clone for ParcelableHolder {
- fn clone(&self) -> ParcelableHolder {
+impl<STABILITY: StabilityType> Default for ParcelableHolder<STABILITY> {
+ fn default() -> Self {
+ Self::new()
+ }
+}
+
+impl<STABILITY: StabilityType> Clone for ParcelableHolder<STABILITY> {
+ fn clone(&self) -> Self {
ParcelableHolder {
data: Mutex::new(self.data.lock().unwrap().clone()),
- stability: self.stability,
+ _stability_phantom: Default::default(),
}
}
}
-impl Serialize for ParcelableHolder {
+impl<STABILITY: StabilityType> Serialize for ParcelableHolder<STABILITY> {
fn serialize(&self, parcel: &mut BorrowedParcel<'_>) -> Result<(), StatusCode> {
parcel.write(&NON_NULL_PARCELABLE_FLAG)?;
self.write_to_parcel(parcel)
}
}
-impl Deserialize for ParcelableHolder {
+impl<STABILITY: StabilityType> Deserialize for ParcelableHolder<STABILITY> {
type UninitType = Self;
fn uninit() -> Self::UninitType {
- Self::new(Default::default())
+ Self::new()
}
fn from_init(value: Self) -> Self::UninitType {
value
@@ -191,16 +202,16 @@
if status == NULL_PARCELABLE_FLAG {
Err(StatusCode::UNEXPECTED_NULL)
} else {
- let mut parcelable = ParcelableHolder::new(Default::default());
+ let mut parcelable = Self::new();
parcelable.read_from_parcel(parcel)?;
Ok(parcelable)
}
}
}
-impl Parcelable for ParcelableHolder {
+impl<STABILITY: StabilityType> Parcelable for ParcelableHolder<STABILITY> {
fn write_to_parcel(&self, parcel: &mut BorrowedParcel<'_>) -> Result<(), StatusCode> {
- parcel.write(&self.stability)?;
+ parcel.write(&STABILITY::VALUE)?;
let mut data = self.data.lock().unwrap();
match *data {
@@ -236,7 +247,7 @@
}
fn read_from_parcel(&mut self, parcel: &BorrowedParcel<'_>) -> Result<(), StatusCode> {
- if self.stability != parcel.read()? {
+ if self.get_stability() != parcel.read()? {
return Err(StatusCode::BAD_VALUE);
}