ofz#4436 check if seek succeeded

Change-Id: I56d9692647b28c706b56ccacf08d494b3d830d94
Reviewed-on: https://gerrit.libreoffice.org/45295Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>

filter/source/msfilter/msdffimp.cxx

@@ -6031,7 +6031,10 @@ bool SvxMSDffManager::GetShapeGroupContainerData( SvStream& rSt,
                 return false;
         }
         else
-            rSt.SeekRel( nLength );
+        {
+            if (!checkSeek(rSt, rSt.Tell() + nLength))
+                return false;
+        }
         nReadSpGrCont += nLength;
     }
     while( nReadSpGrCont < nLenShapeGroupCont );

sd/source/filter/ppt/pptin.cxx

@@ -857,7 +857,7 @@ bool ImplSdPPTImport::Import()
                         bool bSuccess = aHd.SeekToEndOfRecord(rStCtrl);
                         if (!bSuccess)
                         {
-                            SAL_WARN("filter.ms", "Count not seek to end of record");
+                            SAL_WARN("filter.ms", "Could not seek to end of record");
                             break;
                         }
                     }