diff --git a/codec/src/main/java/io/netty/handler/codec/ByteToByteDecoder.java b/codec/src/main/java/io/netty/handler/codec/ByteToByteDecoder.java
index 018a68e743..a2ad13ead7 100644
--- a/codec/src/main/java/io/netty/handler/codec/ByteToByteDecoder.java
+++ b/codec/src/main/java/io/netty/handler/codec/ByteToByteDecoder.java
@@ -82,19 +82,16 @@ public abstract class ByteToByteDecoder extends ChannelInboundByteHandlerAdapter
         int oldOutSize = out.readableBytes();
         try {
             decodeLast(ctx, in, out);
+        } catch (CodecException e) {
+            throw e;
         } catch (Throwable t) {
-            if (t instanceof CodecException) {
-                ctx.fireExceptionCaught(t);
-            } else {
-                ctx.fireExceptionCaught(new DecoderException(t));
+            throw new DecoderException(t);
+        } finally {
+            if (out.readableBytes() > oldOutSize) {
+                ctx.fireInboundBufferUpdated();
             }
+            ctx.fireChannelInactive();
         }
-
-        if (out.readableBytes() > oldOutSize) {
-            ctx.fireInboundBufferUpdated();
-        }
-
-        ctx.fireChannelInactive();
     }
 
     /**
@@ -102,25 +99,23 @@ public abstract class ByteToByteDecoder extends ChannelInboundByteHandlerAdapter
      */
     private void callDecode(ChannelHandlerContext ctx, ByteBuf in, ByteBuf out) {
         int oldOutSize = out.readableBytes();
-        while (in.isReadable()) {
-            int oldInSize = in.readableBytes();
-            try {
-                decode(ctx, in, out);
-            } catch (Throwable t) {
-                if (t instanceof CodecException) {
-                    ctx.fireExceptionCaught(t);
-                } else {
-                    ctx.fireExceptionCaught(new DecoderException(t));
+        try {
+            while (in.isReadable()) {
+                int oldInSize = in.readableBytes();
+                    decode(ctx, in, out);
+                if (oldInSize == in.readableBytes() || isSingleDecode()) {
+                    break;
                 }
             }
-            if (oldInSize == in.readableBytes() || isSingleDecode()) {
-                break;
+        } catch (CodecException e) {
+            throw e;
+        } catch (Throwable t) {
+            throw new DecoderException(t);
+        } finally {
+            if (out.readableBytes() > oldOutSize) {
+                ctx.fireInboundBufferUpdated();
             }
         }
-
-        if (out.readableBytes() > oldOutSize) {
-            ctx.fireInboundBufferUpdated();
-        }
     }
 
     /**
diff --git a/codec/src/main/java/io/netty/handler/codec/ByteToByteEncoder.java b/codec/src/main/java/io/netty/handler/codec/ByteToByteEncoder.java
index 78a3018bdc..f1ed0f9212 100644
--- a/codec/src/main/java/io/netty/handler/codec/ByteToByteEncoder.java
+++ b/codec/src/main/java/io/netty/handler/codec/ByteToByteEncoder.java
@@ -57,28 +57,25 @@ public abstract class ByteToByteEncoder extends ChannelOutboundByteHandlerAdapte
         ByteBuf out = ctx.nextOutboundByteBuffer();
         boolean encoded = false;
 
-        while (in.isReadable()) {
-            int oldInSize = in.readableBytes();
-            try {
+        try {
+            while (in.isReadable()) {
+                int oldInSize = in.readableBytes();
                 encode(ctx, in, out);
                 encoded = true;
-            } catch (Throwable t) {
-                Throwable cause;
-                if (t instanceof CodecException) {
-                    cause = t;
-                } else {
-                    cause = new EncoderException(t);
+                if (oldInSize == in.readableBytes()) {
+                    break;
                 }
-                if (encoded) {
-                    cause = new IncompleteFlushException("unable to encode all bytes", cause);
-                }
-                in.discardSomeReadBytes();
-                promise.setFailure(cause);
-                return;
             }
-            if (oldInSize == in.readableBytes()) {
-                break;
+        } catch (Throwable t) {
+            if (!(t instanceof CodecException)) {
+                t = new EncoderException(t);
             }
+            if (encoded) {
+                t = new IncompleteFlushException("unable to encode all bytes", t);
+            }
+            in.discardSomeReadBytes();
+            promise.setFailure(t);
+            return;
         }
 
         ctx.flush(promise);