[ZH] Fix crash in TunnelContain::killAllContained() when killed occupants kill the host container (#1006)

Author: xezon

GeneralsMD/Code/GameEngine/Include/Common/TunnelTracker.h

@@ -49,6 +49,7 @@ class TunnelTracker : public MemoryPoolObject,
 	UnsignedInt getContainCount() const { return m_containListSize; }
 	Int getContainMax() const;
 	const ContainedItemsList* getContainedItemsList() const { return &m_containList; }	
+	void swapContainedItemsList(ContainedItemsList& newList);
 
 	Bool isValidContainerFor(const Object* obj, Bool checkCapacity) const;
 	void addToContainList( Object *obj );				///< add 'obj' to contain list

GeneralsMD/Code/GameEngine/Source/Common/RTS/TunnelTracker.cpp

@@ -107,6 +107,13 @@ Int TunnelTracker::getContainMax() const
 	return TheGlobalData->m_maxTunnelCapacity;
 }
 
+// ------------------------------------------------------------------------
+void TunnelTracker::swapContainedItemsList(ContainedItemsList& newList)
+{
+	m_containList.swap(newList);
+	m_containListSize = (Int)m_containList.size();
+}
+
 // ------------------------------------------------------------------------
 void TunnelTracker::updateNemesis(const Object *target)
 {

GeneralsMD/Code/GameEngine/Source/GameLogic/Object/Contain/TunnelContain.cpp

@@ -149,18 +149,27 @@ void TunnelContain::harmAndForceExitAllContained( DamageInfo *info )
 //-------------------------------------------------------------------------------------------------
 void TunnelContain::killAllContained( void )
 {
+	// TheSuperHackers @bugfix xezon 04/06/2025 Empty the TunnelSystem's Contained Items List
+	// straight away to prevent a potential child call to catastrophically modify it as well.
+	// This scenario can happen if the killed occupant(s) apply deadly damage on death
+	// to the host container, which then attempts to remove all remaining occupants
+	// on the death of the host container. This is reproducible by shooting with
+	// Neutron Shells on a GLA Tunnel containing GLA Terrorists.
+
+	ContainedItemsList list;
 	Player *owningPlayer = getObject()->getControllingPlayer();
-	const ContainedItemsList *fullList = owningPlayer->getTunnelSystem()->getContainedItemsList();
+	owningPlayer->getTunnelSystem()->swapContainedItemsList(list);
 
-	Object *obj;
-	ContainedItemsList::const_iterator it;
-	it = (*fullList).begin();
-	while( it != (*fullList).end() )
+	ContainedItemsList::iterator it = list.begin();
+
+	while ( it != list.end() )
 	{
-		obj = *it;
-		it++;
+		Object *obj = *it++;
+		DEBUG_ASSERTCRASH( obj, ("Contain list must not contain NULL element"));
+
 		removeFromContain( obj, true );
-    obj->kill();
+
+		obj->kill();
 	}
 }
 //-------------------------------------------------------------------------------------------------