From d793a182c47077fb0aaacfddf680f47aaa741b49 Mon Sep 17 00:00:00 2001
From: wmayer <wmayer@users.sourceforge.net>
Date: Thu, 17 Nov 2022 00:30:44 +0100
Subject: [PATCH] App: fix possible stack overflow in
 GroupExtension::hasObject()

---
 src/App/GroupExtension.cpp | 62 +++++++++++++++++++++-----------------
 src/App/GroupExtension.h   |  4 +--
 2 files changed, 37 insertions(+), 29 deletions(-)

diff --git a/src/App/GroupExtension.cpp b/src/App/GroupExtension.cpp
index e3fd311331..fb9ab4b1a6 100644
--- a/src/App/GroupExtension.cpp
+++ b/src/App/GroupExtension.cpp
@@ -182,34 +182,41 @@ DocumentObject *GroupExtension::getObject(const char *Name) const
 
 bool GroupExtension::hasObject(const DocumentObject* obj, bool recursive) const
 {
-
-    if(obj == getExtendedObject())
+    if (obj == getExtendedObject()) {
         return false;
-
-    const std::vector<DocumentObject*>& grp = Group.getValues();
-    for (auto child : grp) {
-
-        if(!child)
-            continue;
-
-        if (child == obj) {
-            return true;
-        } else if (child == getExtendedObject()) {
-            Base::RuntimeError("Cyclic dependencies detected: Search cannot be performed");
-        } else if ( recursive && child->hasExtension(GroupExtension::getExtensionClassTypeId()) ) {
-
-            App::GroupExtension *subGroup = static_cast<App::GroupExtension *> (
-                                    child->getExtension(GroupExtension::getExtensionClassTypeId()));
-            std::vector<const GroupExtension*> history;
-            history.push_back(this);
-
-            if (subGroup->recursiveHasObject (obj, subGroup, history)) {
-                return true;
-            }
-        }
     }
 
-    return false;
+    try {
+        const std::vector<DocumentObject*>& grp = Group.getValues();
+        for (auto child : grp) {
+
+            if (!child)
+                continue;
+
+            if (child == obj) {
+                return true;
+            }
+            else if (child == getExtendedObject()) {
+                throw Base::RuntimeError("Cyclic dependencies detected: Search cannot be performed");
+            }
+            else if ( recursive && child->hasExtension(GroupExtension::getExtensionClassTypeId()) ) {
+                App::GroupExtension *subGroup = static_cast<App::GroupExtension *> (
+                                        child->getExtension(GroupExtension::getExtensionClassTypeId()));
+                std::vector<const GroupExtension*> history;
+                history.push_back(this);
+
+                if (subGroup->recursiveHasObject (obj, subGroup, history)) {
+                    return true;
+                }
+            }
+        }
+
+        return false;
+    }
+    catch (const Base::RuntimeError& e) {
+        e.ReportException();
+        return false;
+    }
 }
 
 bool GroupExtension::recursiveHasObject(const DocumentObject* obj, const GroupExtension* group, 
@@ -235,8 +242,9 @@ bool GroupExtension::recursiveHasObject(const DocumentObject* obj, const GroupEx
 
             auto ext = child->getExtensionByType<GroupExtension>();
             
-            if(std::find(history.begin(), history.end(), ext) != history.end())
-                Base::RuntimeError("Cyclic dependencies detected: Search cannot be performed");
+            if (std::find(history.begin(), history.end(), ext) != history.end()) {
+                throw Base::RuntimeError("Cyclic dependencies detected: Search cannot be performed");
+            }
 
             if (recursiveHasObject(obj, ext, history)) {
                 return true;
diff --git a/src/App/GroupExtension.h b/src/App/GroupExtension.h
index 189a8ea93b..65d4a583a6 100644
--- a/src/App/GroupExtension.h
+++ b/src/App/GroupExtension.h
@@ -127,8 +127,8 @@ public:
 
 private:
     void removeObjectFromDocument(DocumentObject*);
-    //this version if has object stores the already searched objects to prevent infinite recursion
-    //in case of a cyclic group graph
+    // This function stores the already searched objects to prevent infinite recursion in case of a cyclic group graph
+    // It throws an exception of type Base::RuntimeError if a cyclic dependency is detected.
     bool recursiveHasObject(const DocumentObject* obj, const GroupExtension* group, std::vector<const GroupExtension*> history) const;
 
     // for tracking children visibility