Release DataBuffer in AbstractCharSequenceDecoder

if String creation fails

See gh-35625

Signed-off-by: Marius Lichtblau <marius@lichtblau.io>

spring-core/src/main/java/org/springframework/core/codec/AbstractCharSequenceDecoder.java

@@ -175,14 +175,18 @@ public abstract class AbstractCharSequenceDecoder<T extends CharSequence> extend
 	public final T decode(DataBuffer dataBuffer, ResolvableType elementType,
 			@Nullable MimeType mimeType, @Nullable Map<String, Object> hints) {
 
-		Charset charset = getCharset(mimeType);
-		T value = decodeInternal(dataBuffer, charset);
-		DataBufferUtils.release(dataBuffer);
-		LogFormatUtils.traceDebug(logger, traceOn -> {
-			String formatted = LogFormatUtils.formatValue(value, !traceOn);
-			return Hints.getLogPrefix(hints) + "Decoded " + formatted;
-		});
-		return value;
+		try {
+			Charset charset = getCharset(mimeType);
+			T value = decodeInternal(dataBuffer, charset);
+			LogFormatUtils.traceDebug(logger, traceOn -> {
+				String formatted = LogFormatUtils.formatValue(value, !traceOn);
+				return Hints.getLogPrefix(hints) + "Decoded " + formatted;
+			});
+			return value;
+		}
+		finally {
+			DataBufferUtils.release(dataBuffer);
+		}
 	}
 
 	private Charset getCharset(@Nullable MimeType mimeType) {

spring-core/src/main/java/org/springframework/core/io/buffer/DataBufferLimitException.java

@@ -35,4 +35,8 @@ public class DataBufferLimitException extends IllegalStateException {
 		super(message);
 	}
 
+	public DataBufferLimitException(String message, Throwable cause) {
+		super(message, cause);
+	}
+
 }

spring-core/src/main/java/org/springframework/core/io/buffer/NettyDataBuffer.java

@@ -379,7 +379,12 @@ public class NettyDataBuffer implements PooledDataBuffer {
 
 	@Override
 	public String toString() {
-		return this.byteBuf.toString();
+		try {
+			return this.byteBuf.toString();
+		}
+		catch (OutOfMemoryError ex) {
+			throw new DataBufferLimitException("Failed to convert data buffer to string: " + ex.getMessage(), ex);
+		}
 	}