Merge branch '5.3.x'

# Conflicts:
#	build.gradle

spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/method/annotation/AbstractMessageConverterMethodArgumentResolver.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2021 the original author or authors.
+ * Copyright 2002-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -167,7 +167,7 @@ public abstract class AbstractMessageConverterMethodArgumentResolver implements
 		HttpMethod httpMethod = (inputMessage instanceof HttpRequest ? ((HttpRequest) inputMessage).getMethod() : null);
 		Object body = NO_VALUE;
 
-		EmptyBodyCheckingHttpInputMessage message;
+		EmptyBodyCheckingHttpInputMessage message = null;
 		try {
 			message = new EmptyBodyCheckingHttpInputMessage(inputMessage);
 
@@ -194,6 +194,11 @@ public abstract class AbstractMessageConverterMethodArgumentResolver implements
 		catch (IOException ex) {
 			throw new HttpMessageNotReadableException("I/O error while reading input message", ex, inputMessage);
 		}
+		finally {
+			if (message != null && message.hasBody()) {
+				closeStreamIfNecessary(message.getBody());
+			}
+		}
 
 		if (body == NO_VALUE) {
 			if (httpMethod == null || !SUPPORTED_METHODS.contains(httpMethod) ||
@@ -296,6 +301,15 @@ public abstract class AbstractMessageConverterMethodArgumentResolver implements
 		return arg;
 	}
 
+	/**
+	 * Allow for closing the body stream if necessary,
+	 * e.g. for part streams in a multipart request.
+	 */
+	void closeStreamIfNecessary(InputStream body) {
+		// No-op by default: A standard HttpInputMessage exposes the HTTP request stream
+		// (ServletRequest#getInputStream), with its lifecycle managed by the container.
+	}
+
 
 	private static class EmptyBodyCheckingHttpInputMessage implements HttpInputMessage {
 

spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/method/annotation/RequestPartMethodArgumentResolver.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2021 the original author or authors.
+ * Copyright 2002-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,6 +16,8 @@
 
 package org.springframework.web.servlet.mvc.method.annotation;
 
+import java.io.IOException;
+import java.io.InputStream;
 import java.util.List;
 
 import jakarta.servlet.http.HttpServletRequest;
@@ -180,4 +182,17 @@ public class RequestPartMethodArgumentResolver extends AbstractMessageConverterM
 		return partName;
 	}
 
+	@Override
+	void closeStreamIfNecessary(InputStream body) {
+		// RequestPartServletServerHttpRequest exposes individual part streams,
+		// potentially from temporary files -> explicit close call after resolution
+		// in order to prevent file descriptor leaks.
+		try {
+			body.close();
+		}
+		catch (IOException ex) {
+			// ignore
+		}
+	}
+
 }