Snap for 12710726 from d3ca472da613f281eb09b0ca07b44ce85a35ecfb to 25Q1-release

Change-Id: I65018bf876da48690798e19263e256229959dd22

4 files changed, 102 insertions, 15 deletions

diff --git a/libs/binder/rust/src/system_only.rs b/libs/binder/rust/src/system_only.rs
index 3da59ab811..1a58d6b44d 100644
--- a/libs/binder/rust/src/system_only.rs
+++ b/libs/binder/rust/src/system_only.rs
@@ -91,6 +91,32 @@ impl Accessor {
         Accessor { accessor }
     }
 
+    /// Creates a new Accessor instance based on an existing Accessor's binder.
+    /// This is useful when the Accessor instance is hosted in another process
+    /// that has the permissions to create the socket connection FD.
+    ///
+    /// The `instance` argument must match the instance that the original Accessor
+    /// is responsible for.
+    /// `instance` must not contain null bytes and is used to create a CString to
+    /// pass through FFI.
+    /// The `binder` argument must be a valid binder from an Accessor
+    pub fn from_binder(instance: &str, binder: SpIBinder) -> Option<Accessor> {
+        let inst = CString::new(instance).unwrap();
+
+        // Safety: All `SpIBinder` objects (the `binder` argument) hold a valid pointer
+        // to an `AIBinder` that is guaranteed to remain valid for the lifetime of the
+        // SpIBinder. `ABinderRpc_Accessor_fromBinder` creates a new pointer to that binder
+        // that it is responsible for.
+        // The `inst` argument is a new CString that will copied by
+        // `ABinderRpc_Accessor_fromBinder` and not modified.
+        let accessor =
+            unsafe { sys::ABinderRpc_Accessor_fromBinder(inst.as_ptr(), binder.as_raw()) };
+        if accessor.is_null() {
+            return None;
+        }
+        Some(Accessor { accessor })
+    }
+
     /// Get the underlying binder for this Accessor for when it needs to be either
     /// registered with service manager or sent to another process.
     pub fn as_binder(&self) -> Option<SpIBinder> {
diff --git a/libs/binder/rust/tests/integration.rs b/libs/binder/rust/tests/integration.rs
index 0e793e5761..da4f128e67 100644
--- a/libs/binder/rust/tests/integration.rs
+++ b/libs/binder/rust/tests/integration.rs
@@ -1038,6 +1038,34 @@ mod tests {
         assert!(deleted.load(Ordering::Relaxed));
     }
 
+    #[test]
+    fn test_accessor_from_accessor_binder() {
+        let get_connection_info = move |_instance: &str| None;
+        let accessor = Accessor::new("foo.service", get_connection_info);
+        let accessor2 =
+            Accessor::from_binder("foo.service", accessor.as_binder().unwrap()).unwrap();
+        assert_eq!(accessor.as_binder(), accessor2.as_binder());
+    }
+
+    #[test]
+    fn test_accessor_from_non_accessor_binder() {
+        let service_name = "rust_test_ibinder";
+        let _process = ScopedServiceProcess::new(service_name);
+        let binder = binder::get_service(service_name).unwrap();
+        assert!(binder.is_binder_alive());
+
+        let accessor = Accessor::from_binder("rust_test_ibinder", binder);
+        assert!(accessor.is_none());
+    }
+
+    #[test]
+    fn test_accessor_from_wrong_accessor_binder() {
+        let get_connection_info = move |_instance: &str| None;
+        let accessor = Accessor::new("foo.service", get_connection_info);
+        let accessor2 = Accessor::from_binder("NOT.foo.service", accessor.as_binder().unwrap());
+        assert!(accessor2.is_none());
+    }
+
     #[tokio::test]
     async fn reassociate_rust_binder_async() {
         let service_name = "testing_service";
diff --git a/libs/input/InputConsumerNoResampling.cpp b/libs/input/InputConsumerNoResampling.cpp
index 2c0f77a814..cd8582182a 100644
--- a/libs/input/InputConsumerNoResampling.cpp
+++ b/libs/input/InputConsumerNoResampling.cpp
@@ -169,6 +169,12 @@ InputMessage createTimelineMessage(int32_t inputEventId, nsecs_t gpuCompletedTim
     msg.body.timeline.graphicsTimeline[GraphicsTimeline::PRESENT_TIME] = presentTime;
     return msg;
 }
+
+std::ostream& operator<<(std::ostream& out, const InputMessage& msg) {
+    out << ftl::enum_string(msg.header.type);
+    return out;
+}
+
 } // namespace
 
 // --- InputConsumerNoResampling ---
@@ -272,6 +278,15 @@ void InputConsumerNoResampling::processOutboundEvents() {
             return; // try again later
         }
 
+        if (result == DEAD_OBJECT) {
+            // If there's no one to receive events in the channel, there's no point in sending them.
+            // Drop all outbound events.
+            LOG(INFO) << "Channel " << mChannel->getName() << " died. Dropping outbound event "
+                      << outboundMsg;
+            mOutboundQueue.pop();
+            setFdEvents(0);
+            continue;
+        }
         // Some other error. Give up
         LOG(FATAL) << "Failed to send outbound event on channel '" << mChannel->getName()
                    << "'.  status=" << statusToString(result) << "(" << result << ")";
diff --git a/libs/input/tests/InputPublisherAndConsumerNoResampling_test.cpp b/libs/input/tests/InputPublisherAndConsumerNoResampling_test.cpp
index 39bb841c0a..1dadae98e4 100644
--- a/libs/input/tests/InputPublisherAndConsumerNoResampling_test.cpp
+++ b/libs/input/tests/InputPublisherAndConsumerNoResampling_test.cpp
@@ -319,6 +319,8 @@ protected:
 
 protected:
     // Interaction with the looper thread
+    void blockLooper();
+    void unblockLooper();
     enum class LooperMessage : int {
         CALL_PROBABLY_HAS_INPUT,
         CREATE_CONSUMER,
@@ -389,6 +391,26 @@ private:
     };
 };
 
+void InputPublisherAndConsumerNoResamplingTest::blockLooper() {
+    {
+        std::scoped_lock l(mLock);
+        mLooperMayProceed = false;
+    }
+    sendMessage(LooperMessage::BLOCK_LOOPER);
+    {
+        std::unique_lock l(mLock);
+        mNotifyLooperWaiting.wait(l, [this] { return mLooperIsBlocked; });
+    }
+}
+
+void InputPublisherAndConsumerNoResamplingTest::unblockLooper() {
+    {
+        std::scoped_lock l(mLock);
+        mLooperMayProceed = true;
+    }
+    mNotifyLooperMayProceed.notify_all();
+}
+
 void InputPublisherAndConsumerNoResamplingTest::sendMessage(LooperMessage message) {
     Message msg{ftl::to_underlying(message)};
     mLooper->sendMessage(mMessageHandler, msg);
@@ -600,15 +622,7 @@ void InputPublisherAndConsumerNoResamplingTest::publishAndConsumeSinglePointerMu
     std::queue<uint32_t> publishedSequenceNumbers;
 
     // Block Looper to increase the chance of batching events
-    {
-        std::scoped_lock l(mLock);
-        mLooperMayProceed = false;
-    }
-    sendMessage(LooperMessage::BLOCK_LOOPER);
-    {
-        std::unique_lock l(mLock);
-        mNotifyLooperWaiting.wait(l, [this] { return mLooperIsBlocked; });
-    }
+    blockLooper();
 
     uint32_t firstSampleId;
     for (size_t i = 0; i < nSamples; ++i) {
@@ -629,12 +643,7 @@ void InputPublisherAndConsumerNoResamplingTest::publishAndConsumeSinglePointerMu
 
     std::vector<MotionEvent> singleSampledMotionEvents;
 
-    // Unblock Looper
-    {
-        std::scoped_lock l(mLock);
-        mLooperMayProceed = true;
-    }
-    mNotifyLooperMayProceed.notify_all();
+    unblockLooper();
 
     // We have no control over the socket behavior, so the consumer can receive
     // the motion as a batched event, or as a sequence of multiple single-sample MotionEvents (or a
@@ -809,6 +818,15 @@ void InputPublisherAndConsumerNoResamplingTest::publishAndConsumeTouchModeEvent(
     verifyFinishedSignal(*mPublisher, seq, publishTime);
 }
 
+/**
+ * If the publisher has died, consumer should not crash when trying to send an outgoing message.
+ */
+TEST_F(InputPublisherAndConsumerNoResamplingTest, ConsumerWritesAfterPublisherDies) {
+    mPublisher.reset(); // The publisher has died
+    mReportTimelineArgs.emplace(/*inputEventId=*/10, /*gpuCompletedTime=*/20, /*presentTime=*/30);
+    sendMessage(LooperMessage::CALL_REPORT_TIMELINE);
+}
+
 TEST_F(InputPublisherAndConsumerNoResamplingTest, SendTimeline) {
     const int32_t inputEventId = 20;
     const nsecs_t gpuCompletedTime = 30;