diff --git a/Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/function/editor/StorageAddressEditorDialog.java b/Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/function/editor/StorageAddressEditorDialog.java
index a1aa583fe8..53a6fbe898 100644
--- a/Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/function/editor/StorageAddressEditorDialog.java
+++ b/Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/function/editor/StorageAddressEditorDialog.java
@@ -32,7 +32,8 @@ import ghidra.app.services.DataTypeManagerService;
 import ghidra.app.util.datatype.DataTypeSelectionEditor;
 import ghidra.app.util.datatype.NavigationDirection;
 import ghidra.program.model.address.Address;
-import ghidra.program.model.data.*;
+import ghidra.program.model.data.AbstractFloatDataType;
+import ghidra.program.model.data.DataType;
 import ghidra.program.model.lang.Register;
 import ghidra.program.model.listing.*;
 import ghidra.util.HelpLocation;
@@ -132,12 +133,12 @@ public class StorageAddressEditorDialog extends DialogComponentProvider
 	private void setDataType(DataType dt) {
 		currentDataType = dt;
 		size = dt.getLength();
-		boolean unconstrained = (dt instanceof AbstractFloatDataType) || Undefined.isUndefined(dt);
+		boolean unconstrained = (dt instanceof AbstractFloatDataType) || (dt == DataType.DEFAULT);
 		model.setRequiredSize(size, unconstrained);
 		if (sizeLabel != null) {
 			sizeLabel.setText(Integer.toString(size));
-			dataChanged();
 		}
+		model.notifyDataChanged();
 	}
 
 	private void maybeHandleTabNavigation() {
diff --git a/Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/function/editor/StorageAddressModel.java b/Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/function/editor/StorageAddressModel.java
index 24ddd2bed0..3b833ba13a 100644
--- a/Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/function/editor/StorageAddressModel.java
+++ b/Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/function/editor/StorageAddressModel.java
@@ -155,7 +155,6 @@ class StorageAddressModel {
 
 	void notifyDataChanged() {
 		validate();
-
 		SwingUtilities.invokeLater(() -> listener.dataChanged());
 	}
 
@@ -174,6 +173,7 @@ class StorageAddressModel {
 		}
 		else if (currentSize < requiredSize) {
 			statusText = "Warning: Not enough storage space allocated";
+			return false;
 		}
 		else if (currentSize > requiredSize) {
 			statusText = "Warning: Too much storage space allocated";
diff --git a/Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/function/editor/VarnodeTableModel.java b/Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/function/editor/VarnodeTableModel.java
index 203d9f8120..aebd48c244 100644
--- a/Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/function/editor/VarnodeTableModel.java
+++ b/Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/function/editor/VarnodeTableModel.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.
@@ -155,7 +155,14 @@ class VarnodeTableModel extends AbstractGTableModel<VarnodeInfo> {
 				return;
 			}
 			if (aValue instanceof Address) {
-				storageModel.setVarnode(varnode, (Address) aValue, varnode.getSize());
+				Integer size = varnode.getSize();
+				if (size == null) {
+					size = storageModel.getRequiredSize() - storageModel.getCurrentSize();
+					if (size <= 0) {
+						size = 1;
+					}
+				}
+				storageModel.setVarnode(varnode, (Address) aValue, size);
 			}
 			else if (aValue instanceof Register) {
 				storageModel.setVarnode(varnode, (Register) aValue);
@@ -187,6 +194,9 @@ class VarnodeTableModel extends AbstractGTableModel<VarnodeInfo> {
 			}
 			Address address = varnode.getAddress();
 			int size = (Integer) aValue;
+			if (size <= 0) {
+				return;
+			}
 			if (address != null) {
 				Register reg = varnode.getRegister();
 				if (reg != null && reg.isBigEndian()) {