diff -r 9b702b6608f9 -r 187b92b2e32d src/java.desktop/unix/classes/sun/awt/X11/XDragSourceContextPeer.java
--- a/src/java.desktop/unix/classes/sun/awt/X11/XDragSourceContextPeer.java	Fri Oct 20 20:08:09 2017 -0700
+++ b/src/java.desktop/unix/classes/sun/awt/X11/XDragSourceContextPeer.java	Mon Oct 23 16:55:52 2017 +0530
@@ -38,6 +38,7 @@
 
 import java.util.*;
 
+import sun.java2d.pipe.Region;
 import sun.util.logging.PlatformLogger;
 
 import sun.awt.dnd.SunDragSourceContextPeer;
@@ -811,10 +812,10 @@
     }
 
     public int scaleUp(int x) {
-        return x * windowScale;
+        return Region.clipRound(x * (double)windowScale);
     }
 
     public int scaleDown(int x) {
-        return x / windowScale;
+        return Region.clipRound(x / (double)windowScale);
     }
 }