Fix bug which could generate a NegativeArraySizeException when performing large…

Fix bug which could generate a NegativeArraySizeException when performing large (>40M) row union operations

h2/src/docsrc/html/changelog.html

@@ -37,6 +37,7 @@ Change Log
     should return false
 </li><li>Fix bug which could generate deadlocks when multiple connections accessed the same table.
 </li><li>Some places in the code were not respecting the value set in the "SET MAX_MEMORY_ROWS x" command
+</li><li>Fix bug which could generate a NegativeArraySizeException when performing large (>40M) row union operations
 </li></ul>
 
 <h2>Version 1.4.182 Beta (2014-10-17)</h2>

h2/src/main/org/h2/util/HashBase.java

@@ -96,6 +96,10 @@ public abstract class HashBase {
      * @param newLevel the new level
      */
     protected void reset(int newLevel) {
+        // can't exceed 30 or we will generate a negative value for the "len" field
+        if (newLevel > 30) {
+            newLevel = 30;
+        }
         minSize = size * 3 / 4;
         size = 0;
         level = newLevel;