Fixed a crash involving invalid positions.

src/main/java/net/minecraft/server/NetServerHandler.java

@@ -143,6 +143,18 @@ public class NetServerHandler extends NetHandler implements ICommandListener {
             this.lastYaw = this.e.yaw;
             this.lastPitch = this.e.pitch;
         }
+
+        if (Math.abs(packet10flying.a) > 32000000 || Math.abs(packet10flying.c) > 32000000) {
+            System.err.println(player.getName() + " was caught trying to crash the server with an invalid position.");
+            player.kickPlayer("Nope!");
+            return;
+        }
+
+        if (Math.abs(packet10flying.c) > 32000000) {
+            System.err.println(player.getName() + " was caught trying to crash the server with an invalid position.");
+            player.kickPlayer("Nope!");
+            return;
+        }
         // CraftBukkit end
 
         if (this.l) {