add some sanity checking to HandleAgentRequestSit handler

1 files changed, 12 insertions, 2 deletions

diff --git a/OpenSim/Region/ClientStack/Linden/UDP/LLClientView.cs b/OpenSim/Region/ClientStack/Linden/UDP/LLClientView.cs
index 504df40..a8517e6 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;
         }