Fix bug in forEachByte on nested composite bytebuf with leak detection

buffer/src/main/java/io/netty/buffer/WrappedCompositeByteBuf.java

@@ -408,6 +408,16 @@ public int forEachByteDesc(int index, int length, ByteProcessor processor) {
         return wrapped.forEachByteDesc(index, length, processor);
     }
 
+    @Override
+    protected int forEachByteAsc0(int start, int end, ByteProcessor processor) throws Exception {
+        return wrapped.forEachByteAsc0(start, end, processor);
+    }
+
+    @Override
+    protected int forEachByteDesc0(int rStart, int rEnd, ByteProcessor processor) throws Exception {
+        return wrapped.forEachByteDesc0(rStart, rEnd, processor);
+    }
+
     @Override
     public final int hashCode() {
         return wrapped.hashCode();

buffer/src/test/java/io/netty/buffer/AbstractCompositeByteBufTest.java

@@ -15,6 +15,7 @@
  */
 package io.netty.buffer;
 
+import io.netty.util.ByteProcessor;
 import io.netty.util.ReferenceCountUtil;
 import io.netty.util.internal.ObjectUtil;
 import io.netty.util.internal.PlatformDependent;
@@ -1774,4 +1775,36 @@ public void sliceOfCompositeBufferMustThrowISEAfterDiscardBytes() {
             composite.release();
         }
     }
+
+    @Test
+    public void forEachByteOnNestedCompositeByteBufMustSeeEntireFlattenedContents() {
+        CompositeByteBuf buf = newCompositeBuffer();
+        buf.addComponent(true, newCompositeBuffer().addComponents(
+                true,
+                wrappedBuffer(new byte[] {1, 2, 3}),
+                wrappedBuffer(new byte[] {4, 5, 6})));
+        final byte[] arrayAsc = new byte[6];
+        final byte[] arrayDesc = new byte[6];
+        buf.forEachByte(new ByteProcessor() {
+            int index;
+
+            @Override
+            public boolean process(byte value) throws Exception {
+                arrayAsc[index++] = value;
+                return true;
+            }
+        });
+        buf.forEachByteDesc(new ByteProcessor() {
+            int index;
+
+            @Override
+            public boolean process(byte value) throws Exception {
+                arrayDesc[index++] = value;
+                return true;
+            }
+        });
+        assertArrayEquals(new byte[] {1, 2, 3, 4, 5, 6}, arrayAsc);
+        assertArrayEquals(new byte[] {6, 5, 4, 3, 2, 1}, arrayDesc);
+        buf.release();
+    }
 }