Description: Do not accept a scaling factor of zero (CVE-2014-6054)
 Do not accept a scaling factor of zero on
 PalmVNCSetScaleFactor and SetScale client->server messages. This would cause
 a division by zero and crash the server.
Origin: https://github.com/newsoft/libvncserver/commit/05a9bd41a8ec0a9d580a8f420f41718bdd235446
---
This patch header follows DEP-3: http://dep.debian.net/deps/dep3/
Index: libvncserver-0.9.9+dfsg/libvncserver/rfbserver.c
===================================================================
--- libvncserver-0.9.9+dfsg.orig/libvncserver/rfbserver.c
+++ libvncserver-0.9.9+dfsg/libvncserver/rfbserver.c
@@ -2487,6 +2487,13 @@ rfbProcessClientNormalMessage(rfbClientP
           rfbCloseClient(cl);
           return;
       }
+
+      if (msg.ssc.scale == 0) {
+          rfbLogPerror("rfbProcessClientNormalMessage: will not accept a scale factor of zero");
+          rfbCloseClient(cl);
+          return;
+      }
+
       rfbStatRecordMessageRcvd(cl, msg.type, sz_rfbSetScaleMsg, sz_rfbSetScaleMsg);
       rfbLog("rfbSetScale(%d)\n", msg.ssc.scale);
       rfbScalingSetup(cl,cl->screen->width/msg.ssc.scale, cl->screen->height/msg.ssc.scale);
@@ -2503,6 +2510,13 @@ rfbProcessClientNormalMessage(rfbClientP
           rfbCloseClient(cl);
           return;
       }
+
+      if (msg.ssc.scale == 0) {
+          rfbLogPerror("rfbProcessClientNormalMessage: will not accept a scale factor of zero");
+          rfbCloseClient(cl);
+          return;
+      }
+
       rfbStatRecordMessageRcvd(cl, msg.type, sz_rfbSetScaleMsg, sz_rfbSetScaleMsg);
       rfbLog("rfbSetScale(%d)\n", msg.ssc.scale);
       rfbScalingSetup(cl,cl->screen->width/msg.ssc.scale, cl->screen->height/msg.ssc.scale);