guard against corrupt RootData

Change-Id: Iad2788a7e5e7ee3b3107eab37cde2d3d38eae005
(cherry picked from commit fc943ea8)
Reviewed-on: https://gerrit.libreoffice.org/20495Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>

lotuswordpro/source/filter/lwpidxmgr.cxx

@@ -152,7 +152,10 @@ void LwpIndexManager::ReadRootData(LwpObjectStream* pObjStrm)
     sal_uInt16 KeyCount = pObjStrm->QuickReaduInt16();
     m_nLeafCount = KeyCount ? KeyCount + 1 : 0;
 
-    if(KeyCount)
+    if (m_nLeafCount > SAL_N_ELEMENTS(m_ChildIndex))
+        throw std::range_error("corrupt RootData");
+
+    if (KeyCount)
     {
         //read object keys
         LwpKey* akey = new LwpKey();

lotuswordpro/source/filter/lwptabrack.cxx

@@ -92,7 +92,7 @@ void LwpTabRack::Read()
 
     m_nNumTabs = m_pObjStrm->QuickReaduInt16();
     if (m_nNumTabs > MaxTabs)
-        throw std::out_of_range("corrupt LwpTabRack");
+        throw std::range_error("corrupt LwpTabRack");
     for (int i=0; i<m_nNumTabs; ++i)
     {
         m_aTabs[i].Read(m_pObjStrm);