From af27180131594949b77129cac53e34e0506aa4eb Mon Sep 17 00:00:00 2001
From: dahlia <dahliaTrimble@removeme.gmail.com>
Date: Thu, 10 Jan 2013 20:21:18 -0800
Subject: [PATCH] add some sanity checking to HandleAgentRequestSit handler

---
 .../Region/ClientStack/Linden/UDP/LLClientView.cs  | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/OpenSim/Region/ClientStack/Linden/UDP/LLClientView.cs b/OpenSim/Region/ClientStack/Linden/UDP/LLClientView.cs
index 504df40e63..a8517e60f3 100644
--- a/OpenSim/Region/ClientStack/Linden/UDP/LLClientView.cs
+++ b/OpenSim/Region/ClientStack/Linden/UDP/LLClientView.cs
@@ -6428,8 +6428,18 @@ namespace OpenSim.Region.ClientStack.LindenUDP
 
                 AgentRequestSit handlerAgentRequestSit = OnAgentRequestSit;
                 if (handlerAgentRequestSit != null)
-                    handlerAgentRequestSit(this, agentRequestSit.AgentData.AgentID,
-                                           agentRequestSit.TargetObject.TargetID, agentRequestSit.TargetObject.Offset);
+                    if (!(agentRequestSit.AgentData == null
+                        || agentRequestSit.TargetObject == null
+                        || agentRequestSit.TargetObject.TargetID == null
+                        || agentRequestSit.TargetObject.Offset == null))
+                    {
+                        var sp = m_scene.GetScenePresence(agentRequestSit.AgentData.AgentID);
+                        if (sp == null || sp.ParentID != 0) // ignore packet if agent is already sitting
+                            return true;
+
+                        handlerAgentRequestSit(this, agentRequestSit.AgentData.AgentID,
+                                               agentRequestSit.TargetObject.TargetID, agentRequestSit.TargetObject.Offset);
+                    }
             }
             return true;
         }