From ae87c7005c85aad90874fa9991d330a547565e91 Mon Sep 17 00:00:00 2001
From: Monty Montgomery <xiphmont@gmail.com>
Date: Sun, 15 May 2022 00:39:44 -0400
Subject: [PATCH] Two nullptr deref fixes in table

Don't delete memory that wasn't allocated.

Similarly, we can't deref the first element of an array that was never
allocated.
---
 libsrc/general/table.cpp | 10 ++++++----
 libsrc/general/table.hpp |  3 ++-
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/libsrc/general/table.cpp b/libsrc/general/table.cpp
index 732d63c3..e39d671b 100644
--- a/libsrc/general/table.cpp
+++ b/libsrc/general/table.cpp
@@ -108,14 +108,16 @@ namespace netgen
     if (line.size == line.maxsize)
       {
 	void * p = new char [(line.maxsize+5) * elsize];
-      
-	memcpy (p, line.col, line.maxsize * elsize);
-	delete [] (char*)line.col;
+
+        if (line.size > 0 && line.col != NULL) {
+          memcpy (p, line.col, line.maxsize * elsize);
+          delete [] (char*)line.col;
+        }
 
 	line.col = p;
 	line.maxsize += 5;
       }
-  
+
     line.size++;
   }
 
diff --git a/libsrc/general/table.hpp b/libsrc/general/table.hpp
index 535d0212..44c5f9fb 100644
--- a/libsrc/general/table.hpp
+++ b/libsrc/general/table.hpp
@@ -120,7 +120,8 @@ public:
   
   /// Creates fixed maximal element size table
   inline TABLE (const NgFlatArray<int,BASE> & entrysizes)
-    : BASE_TABLE (NgFlatArray<int> (entrysizes.Size(), const_cast<int*>(&entrysizes[BASE])), 
+    : BASE_TABLE (NgFlatArray<int> (entrysizes.Size(),
+                                    entrysizes.Size() > 0 ? const_cast<int*>(&entrysizes[BASE]) : 0), 
 		  sizeof(T))
   { ; }