From 535645f6a75943d27cdfca5a1d537ebc2c630a15 Mon Sep 17 00:00:00 2001
From: emteere <47253321+emteere@users.noreply.github.com>
Date: Wed, 2 Oct 2024 15:14:41 -0400
Subject: [PATCH] GP-4696 Clear data from a clearflow and repair, only if the
 information there could have been created from simple disassembly

---
 .../plugin/core/clear/ClearFlowAndRepairCmd.java | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/clear/ClearFlowAndRepairCmd.java b/Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/clear/ClearFlowAndRepairCmd.java
index c44d032b3c..8cc840ba4b 100644
--- a/Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/clear/ClearFlowAndRepairCmd.java
+++ b/Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/clear/ClearFlowAndRepairCmd.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.
@@ -26,6 +26,7 @@ import ghidra.program.disassemble.Disassembler;
 import ghidra.program.disassemble.DisassemblerContextImpl;
 import ghidra.program.model.address.*;
 import ghidra.program.model.block.*;
+import ghidra.program.model.data.Undefined;
 import ghidra.program.model.lang.Register;
 import ghidra.program.model.lang.RegisterValue;
 import ghidra.program.model.listing.*;
@@ -308,8 +309,17 @@ public class ClearFlowAndRepairCmd extends BackgroundCommand<Program> {
 					}
 					// no instruction, check if data is there
 					Data data = listing.getDefinedDataAt(toAddr);
+					// data or instruction not found at destination
 					if (data == null) {
-						continue; // instruction not found at destination
+						continue; // don't add to clear set
+					}
+					// has an external reference from data, not produced from bad flow
+					if (data.getExternalReference(0) != null) {
+						continue; // don't add to clear set
+					}
+					// if defined data is anything other than Undefined1,2... or a pointer
+					if (data.isDefined() && !(data.getDataType() instanceof Undefined) && !(data.isPointer())) {
+						continue; // don't add to clear set
 					}
 				}
 				boolean clearIt = true;