diff --git a/GPL/DMG/src/dmg/java/mobiledevices/dmg/btree/BTreeRootNodeDescriptor.java b/GPL/DMG/src/dmg/java/mobiledevices/dmg/btree/BTreeRootNodeDescriptor.java
index 9279cff65c..abc8eba70c 100644
--- a/GPL/DMG/src/dmg/java/mobiledevices/dmg/btree/BTreeRootNodeDescriptor.java
+++ b/GPL/DMG/src/dmg/java/mobiledevices/dmg/btree/BTreeRootNodeDescriptor.java
@@ -25,7 +25,10 @@ public class BTreeRootNodeDescriptor extends BTreeNodeDescriptor {
 
 		nodes.add( this );
 
-		int nodeSize = headerRecord.getNodeSize() & 0xffff;
+		int nodeSize = Short.toUnsignedInt(headerRecord.getNodeSize());
+		if (nodeSize == 0) {
+			throw new IOException("Bad nodeSize: " + nodeSize);
+		}
 
 		for ( int i = nodeSize ; i < reader.length() ; i += nodeSize ) {
 			reader.setPointerIndex( i );
diff --git a/Ghidra/Features/FileFormats/src/main/java/ghidra/file/formats/ios/btree/BTreeRootNodeDescriptor.java b/Ghidra/Features/FileFormats/src/main/java/ghidra/file/formats/ios/btree/BTreeRootNodeDescriptor.java
index 2302522ecd..c9dc638ff3 100644
--- a/Ghidra/Features/FileFormats/src/main/java/ghidra/file/formats/ios/btree/BTreeRootNodeDescriptor.java
+++ b/Ghidra/Features/FileFormats/src/main/java/ghidra/file/formats/ios/btree/BTreeRootNodeDescriptor.java
@@ -4,9 +4,9 @@
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
- * 
+ *
  *      http://www.apache.org/licenses/LICENSE-2.0
- * 
+ *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
@@ -15,15 +15,15 @@
  */
 package ghidra.file.formats.ios.btree;
 
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+
 import ghidra.app.util.bin.BinaryReader;
 import ghidra.app.util.bin.StructConverterUtil;
 import ghidra.program.model.data.DataType;
 import ghidra.util.exception.DuplicateNameException;
 
-import java.io.IOException;
-import java.util.ArrayList;
-import java.util.List;
-
 public class BTreeRootNodeDescriptor extends BTreeNodeDescriptor {
 
 	private BTreeHeaderRecord headerRecord;
@@ -40,7 +40,10 @@ public class BTreeRootNodeDescriptor extends BTreeNodeDescriptor {
 
 		nodes.add( this );
 
-		int nodeSize = headerRecord.getNodeSize() & 0xffff;
+		int nodeSize = Short.toUnsignedInt(headerRecord.getNodeSize());
+		if (nodeSize == 0) {
+			throw new IOException("Bad nodeSize: " + nodeSize);
+		}
 
 		for ( int i = nodeSize ; i < reader.length() ; i += nodeSize ) {
 			reader.setPointerIndex( i );