Fixed a thread safety issue that could cause application to crash in …

.changes/next-release/bugfix-AWSCRTHTTPClient-7b95a65.json

@@ -0,0 +1,6 @@
+{
+    "type": "bugfix",
+    "category": "AWS CRT HTTP Client",
+    "contributor": "",
+    "description": "Fixed a thread safety issue that could cause application to crash in the edge case where the SDK attempted to invoke `incrementWindow` after the stream is closed in AWS CRT HTTP Client."
+}

bom-internal/pom.xml

@@ -255,6 +255,12 @@
                 <version>${mockito.version}</version>
                 <scope>test</scope>
             </dependency>
+            <dependency>
+                <groupId>org.mockito</groupId>
+                <artifactId>mockito-inline</artifactId>
+                <version>${mockito.version}</version>
+                <scope>test</scope>
+            </dependency>
             <dependency>
                 <groupId>nl.jqno.equalsverifier</groupId>
                 <artifactId>equalsverifier</artifactId>

http-clients/aws-crt-client/pom.xml

@@ -105,7 +105,7 @@
         </dependency>
         <dependency>
             <groupId>org.mockito</groupId>
-            <artifactId>mockito-core</artifactId>
+            <artifactId>mockito-inline</artifactId>
             <scope>test</scope>
         </dependency>
         <dependency>

http-clients/aws-crt-client/src/main/java/software/amazon/awssdk/http/crt/internal/response/CrtResponseAdapter.java

@@ -20,6 +20,7 @@
 import java.nio.ByteBuffer;
 import java.util.concurrent.CompletableFuture;
 import software.amazon.awssdk.annotations.SdkInternalApi;
+import software.amazon.awssdk.annotations.SdkTestInternalApi;
 import software.amazon.awssdk.crt.CRT;
 import software.amazon.awssdk.crt.http.HttpClientConnection;
 import software.amazon.awssdk.crt.http.HttpException;
@@ -46,19 +47,29 @@ public final class CrtResponseAdapter implements HttpStreamResponseHandler {
     private final HttpClientConnection connection;
     private final CompletableFuture<Void> completionFuture;
     private final SdkAsyncHttpResponseHandler responseHandler;
-    private final SimplePublisher<ByteBuffer> responsePublisher = new SimplePublisher<>();
+    private final SimplePublisher<ByteBuffer> responsePublisher;
 
     private final SdkHttpResponse.Builder responseBuilder;
     private final ResponseHandlerHelper responseHandlerHelper;
 
     private CrtResponseAdapter(HttpClientConnection connection,
                                CompletableFuture<Void> completionFuture,
                                SdkAsyncHttpResponseHandler responseHandler) {
+        this(connection, completionFuture, responseHandler, new SimplePublisher<>());
+    }
+
+
+    @SdkTestInternalApi
+    public CrtResponseAdapter(HttpClientConnection connection,
+                               CompletableFuture<Void> completionFuture,
+                               SdkAsyncHttpResponseHandler responseHandler,
+                               SimplePublisher<ByteBuffer> simplePublisher) {
         this.connection = Validate.paramNotNull(connection, "connection");
         this.completionFuture = Validate.paramNotNull(completionFuture, "completionFuture");
         this.responseHandler = Validate.paramNotNull(responseHandler, "responseHandler");
         this.responseBuilder = SdkHttpResponse.builder();
         this.responseHandlerHelper = new ResponseHandlerHelper(responseBuilder, connection);
+        this.responsePublisher = simplePublisher;
     }
 
     public static HttpStreamResponseHandler toCrtResponseHandler(HttpClientConnection crtConn,
@@ -95,9 +106,7 @@ public int onResponseBody(HttpStream stream, byte[] bodyBytesIn) {
                 return;
             }
 
-            if (!responseHandlerHelper.connectionClosed().get()) {
-                stream.incrementWindow(bodyBytesIn.length);
-            }
+            responseHandlerHelper.incrementWindow(stream, bodyBytesIn.length);
         });
 
         return 0;

http-clients/aws-crt-client/src/main/java/software/amazon/awssdk/http/crt/internal/response/InputStreamAdaptingHttpStreamResponseHandler.java

@@ -20,6 +20,7 @@
 import java.nio.ByteBuffer;
 import java.util.concurrent.CompletableFuture;
 import software.amazon.awssdk.annotations.SdkInternalApi;
+import software.amazon.awssdk.annotations.SdkTestInternalApi;
 import software.amazon.awssdk.crt.CRT;
 import software.amazon.awssdk.crt.http.HttpClientConnection;
 import software.amazon.awssdk.crt.http.HttpException;
@@ -42,7 +43,7 @@
 public final class InputStreamAdaptingHttpStreamResponseHandler implements HttpStreamResponseHandler {
     private static final Logger log = Logger.loggerFor(InputStreamAdaptingHttpStreamResponseHandler.class);
     private volatile AbortableInputStreamSubscriber inputStreamSubscriber;
-    private final SimplePublisher<ByteBuffer> simplePublisher = new SimplePublisher<>();
+    private final SimplePublisher<ByteBuffer> simplePublisher;
 
     private final CompletableFuture<SdkHttpFullResponse> requestCompletionFuture;
     private final HttpClientConnection crtConn;
@@ -52,10 +53,18 @@ public final class InputStreamAdaptingHttpStreamResponseHandler implements HttpS
 
     public InputStreamAdaptingHttpStreamResponseHandler(HttpClientConnection crtConn,
                                                         CompletableFuture<SdkHttpFullResponse> requestCompletionFuture) {
+        this(crtConn, requestCompletionFuture, new SimplePublisher<>());
+    }
+
+    @SdkTestInternalApi
+    public InputStreamAdaptingHttpStreamResponseHandler(HttpClientConnection crtConn,
+                                                        CompletableFuture<SdkHttpFullResponse> requestCompletionFuture,
+                                                        SimplePublisher<ByteBuffer> simplePublisher) {
         this.crtConn = crtConn;
         this.requestCompletionFuture = requestCompletionFuture;
         this.responseBuilder = SdkHttpResponse.builder();
         this.responseHandlerHelper = new ResponseHandlerHelper(responseBuilder, crtConn);
+        this.simplePublisher = simplePublisher;
     }
 
     @Override
@@ -101,11 +110,8 @@ public int onResponseBody(HttpStream stream, byte[] bodyBytesIn) {
                 failFutureAndCloseConnection(stream, failure);
                 return;
             }
-
-            if (!responseHandlerHelper.connectionClosed().get()) {
-                // increment the window upon buffer consumption.
-                stream.incrementWindow(bodyBytesIn.length);
-            }
+            // increment the window upon buffer consumption.
+            responseHandlerHelper.incrementWindow(stream, bodyBytesIn.length);
         });
 
         // Window will be incremented after the subscriber consumes the data, returning 0 here to disable it.

http-clients/aws-crt-client/src/main/java/software/amazon/awssdk/http/crt/internal/response/ResponseHandlerHelper.java

@@ -15,7 +15,6 @@
 
 package software.amazon.awssdk.http.crt.internal.response;
 
-import java.util.concurrent.atomic.AtomicBoolean;
 import software.amazon.awssdk.annotations.SdkInternalApi;
 import software.amazon.awssdk.crt.http.HttpClientConnection;
 import software.amazon.awssdk.crt.http.HttpHeader;
@@ -30,14 +29,16 @@
  *
  * CRT connection will only be closed, i.e., not reused, in one of the following conditions:
  * 1. 5xx server error OR
- * 2. It fails to read the response.
+ * 2. It fails to read the response OR
+ * 3. the response stream is closed/aborted by the caller.
  */
 @SdkInternalApi
 public class ResponseHandlerHelper {
 
     private final SdkHttpResponse.Builder responseBuilder;
     private final HttpClientConnection connection;
-    private AtomicBoolean connectionClosed = new AtomicBoolean(false);
+    private boolean connectionClosed;
+    private final Object lock = new Object();
 
     public ResponseHandlerHelper(SdkHttpResponse.Builder responseBuilder, HttpClientConnection connection) {
         this.responseBuilder = responseBuilder;
@@ -57,20 +58,34 @@ public void onResponseHeaders(HttpStream stream, int responseStatusCode, int hea
      * Release the connection back to the pool so that it can be reused.
      */
     public void releaseConnection(HttpStream stream) {
-        if (connectionClosed.compareAndSet(false, true)) {
-            connection.close();
-            stream.close();
+        synchronized (lock) {
+            if (!connectionClosed) {
+                connectionClosed = true;
+                connection.close();
+                stream.close();
+            }
+        }
+    }
+
+    public void incrementWindow(HttpStream stream, int windowSize) {
+        synchronized (lock) {
+            if (!connectionClosed) {
+                stream.incrementWindow(windowSize);
+            }
         }
     }
 
     /**
      * Close the connection completely
      */
     public void closeConnection(HttpStream stream) {
-        if (connectionClosed.compareAndSet(false, true)) {
-            connection.shutdown();
-            connection.close();
-            stream.close();
+        synchronized (lock) {
+            if (!connectionClosed) {
+                connectionClosed = true;
+                connection.shutdown();
+                connection.close();
+                stream.close();
+            }
         }
     }
 
@@ -82,8 +97,4 @@ public void cleanUpConnectionBasedOnStatusCode(HttpStream stream) {
             releaseConnection(stream);
         }
     }
-
-    public AtomicBoolean connectionClosed() {
-        return connectionClosed;
-    }
 }

http-clients/aws-crt-client/src/test/java/software/amazon/awssdk/http/crt/internal/BaseHttpStreamResponseHandlerTest.java

@@ -16,25 +16,34 @@
 package software.amazon.awssdk.http.crt.internal;
 
 import static org.assertj.core.api.Assertions.assertThatThrownBy;
+import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyInt;
 import static org.mockito.Mockito.never;
 import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
 
+import java.nio.ByteBuffer;
 import java.nio.charset.StandardCharsets;
 import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicInteger;
+import org.apache.commons.lang3.RandomStringUtils;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.ValueSource;
 import org.mockito.Mock;
+import org.mockito.Mockito;
 import org.mockito.junit.jupiter.MockitoExtension;
 import software.amazon.awssdk.crt.http.HttpClientConnection;
 import software.amazon.awssdk.crt.http.HttpException;
 import software.amazon.awssdk.crt.http.HttpHeader;
 import software.amazon.awssdk.crt.http.HttpHeaderBlock;
 import software.amazon.awssdk.crt.http.HttpStream;
 import software.amazon.awssdk.crt.http.HttpStreamResponseHandler;
+import software.amazon.awssdk.http.crt.internal.response.InputStreamAdaptingHttpStreamResponseHandler;
+import software.amazon.awssdk.utils.async.SimplePublisher;
 
 @ExtendWith(MockitoExtension.class)
 public abstract class BaseHttpStreamResponseHandlerTest {
@@ -44,10 +53,15 @@ public abstract class BaseHttpStreamResponseHandlerTest {
     @Mock
     HttpStream httpStream;
 
+    @Mock
+    SimplePublisher<ByteBuffer> simplePublisher;
+
     HttpStreamResponseHandler responseHandler;
 
     abstract HttpStreamResponseHandler responseHandler();
 
+    abstract HttpStreamResponseHandler responseHandlerWithMockedPublisher(SimplePublisher<ByteBuffer> simplePublisher);
+
     @BeforeEach
     public void setUp() {
         requestFuture = new CompletableFuture<>();
@@ -113,6 +127,101 @@ void streamClosed_shouldNotIncreaseStreamWindow() throws InterruptedException {
         verify(httpStream, never()).incrementWindow(anyInt());
     }
 
+    @Test
+    void publisherWritesFutureFails_shouldShutdownConnection() {
+        SimplePublisher<ByteBuffer> simplePublisher = Mockito.mock(SimplePublisher.class);
+        CompletableFuture<Void> future = new CompletableFuture<>();
+        when(simplePublisher.send(any(ByteBuffer.class))).thenReturn(future);
+
+        HttpStreamResponseHandler handler = responseHandlerWithMockedPublisher(simplePublisher);
+        HttpHeader[] httpHeaders = getHttpHeaders();
+
+        handler.onResponseHeaders(httpStream, 200, HttpHeaderBlock.MAIN.getValue(),
+                                  httpHeaders);
+        handler.onResponseHeadersDone(httpStream, 0);
+        handler.onResponseBody(httpStream,
+                               RandomStringUtils.random(1 * 1024 * 1024).getBytes(StandardCharsets.UTF_8));
+        RuntimeException runtimeException = new RuntimeException();
+        future.completeExceptionally(runtimeException);
+
+        try {
+            requestFuture.join();
+        } catch (Exception e) {
+            // we don't verify here because it behaves differently in async and sync
+        }
+
+        verify(crtConn).shutdown();
+        verify(crtConn).close();
+        verify(httpStream).close();
+        verify(httpStream, never()).incrementWindow(anyInt());
+    }
+
+    @Test
+    void publisherWritesFutureCompletesAfterConnectionClosed_shouldNotInvokeIncrementWindow() {
+        CompletableFuture<Void> future = new CompletableFuture<>();
+        when(simplePublisher.send(any(ByteBuffer.class))).thenReturn(future);
+        when(simplePublisher.complete()).thenReturn(future);
+
+        HttpStreamResponseHandler handler = responseHandlerWithMockedPublisher(simplePublisher);
+
+
+        HttpHeader[] httpHeaders = getHttpHeaders();
+
+        handler.onResponseHeaders(httpStream, 200, HttpHeaderBlock.MAIN.getValue(),
+                                  httpHeaders);
+        handler.onResponseHeadersDone(httpStream, 0);
+        handler.onResponseBody(httpStream,
+                               RandomStringUtils.random(1 * 1024 * 1024).getBytes(StandardCharsets.UTF_8));
+        handler.onResponseComplete(httpStream, 0);
+        future.complete(null);
+
+        requestFuture.join();
+        verify(crtConn, never()).shutdown();
+        verify(crtConn).close();
+        verify(httpStream).close();
+        verify(httpStream, never()).incrementWindow(anyInt());
+    }
+
+    @Test
+    void publisherWritesFutureCompletesWhenConnectionClosed_shouldNotInvokeIncrementWindow() {
+        CompletableFuture<Void> future = new CompletableFuture<>();
+        when(simplePublisher.send(any(ByteBuffer.class))).thenReturn(future);
+        when(simplePublisher.complete()).thenReturn(future);
+
+        HttpStreamResponseHandler handler = responseHandlerWithMockedPublisher(simplePublisher);
+
+
+        HttpHeader[] httpHeaders = getHttpHeaders();
+
+        handler.onResponseHeaders(httpStream, 200, HttpHeaderBlock.MAIN.getValue(),
+                                  httpHeaders);
+        handler.onResponseHeadersDone(httpStream, 0);
+        handler.onResponseBody(httpStream,
+                               RandomStringUtils.random(1 * 1024 * 1024).getBytes(StandardCharsets.UTF_8));
+
+        // This tracker tracks which of the two operation completes first
+        AtomicInteger whenCompleteTracker = new AtomicInteger(0);
+        CompletableFuture<Void> onResponseComplete = CompletableFuture.runAsync(() -> handler.onResponseComplete(httpStream, 0))
+                                                           .whenComplete((r, t) -> whenCompleteTracker.compareAndSet(0, 1));
+
+        CompletableFuture<Void> writeComplete = CompletableFuture.runAsync(() -> future.complete(null))
+                                                           .whenComplete((r, t) -> whenCompleteTracker.compareAndSet(0, 2));
+        requestFuture.join();
+
+        CompletableFuture.allOf(onResponseComplete, writeComplete).join();
+
+        if (whenCompleteTracker.get() == 1) {
+            // onResponseComplete finishes first
+            verify(httpStream, never()).incrementWindow(anyInt());
+        } else {
+            verify(httpStream).incrementWindow(anyInt());
+        }
+
+        verify(crtConn, never()).shutdown();
+        verify(crtConn).close();
+        verify(httpStream).close();
+    }
+
     static HttpHeader[] getHttpHeaders() {
         HttpHeader[] httpHeaders = new HttpHeader[1];
         httpHeaders[0] = new HttpHeader("Content-Length", "1");

http-clients/aws-crt-client/src/test/java/software/amazon/awssdk/http/crt/internal/CrtResponseHandlerTest.java

@@ -41,6 +41,7 @@
 import software.amazon.awssdk.http.async.SdkAsyncHttpResponseHandler;
 import software.amazon.awssdk.http.crt.internal.response.CrtResponseAdapter;
 import software.amazon.awssdk.http.crt.internal.response.InputStreamAdaptingHttpStreamResponseHandler;
+import software.amazon.awssdk.utils.async.SimplePublisher;
 
 public class CrtResponseHandlerTest extends BaseHttpStreamResponseHandlerTest {
 
@@ -53,6 +54,15 @@ HttpStreamResponseHandler responseHandler() {
         return CrtResponseAdapter.toCrtResponseHandler(crtConn, requestFuture, responseHandler);
     }
 
+    @Override
+    HttpStreamResponseHandler responseHandlerWithMockedPublisher(SimplePublisher<ByteBuffer> simplePublisher) {
+        AsyncResponseHandler<Void> responseHandler = new AsyncResponseHandler<>((response,
+                                                                                 executionAttributes) -> null, Function.identity(), new ExecutionAttributes());
+
+        responseHandler.prepare();
+        return new CrtResponseAdapter(crtConn, requestFuture, responseHandler, simplePublisher);
+    }
+
     @Test
     void publisherFailedToDeliverEvents_shouldShutDownConnection() {
         SdkAsyncHttpResponseHandler responseHandler = new TestAsyncHttpResponseHandler();