check if pool is ready before sending next request

libi2pd/NetDbRequests.cpp

@@ -199,6 +199,8 @@ namespace data
 				else
 				{	
 					auto pool = i2p::tunnel::tunnels.GetExploratoryPool ();
+					if (pool)
+					{	
 						auto outbound = pool->GetNextOutboundTunnel ();
 						auto inbound = pool->GetNextInboundTunnel ();
 						if (nextFloodfill && outbound && inbound)
@@ -216,6 +218,12 @@ namespace data
 							if (!outbound) LogPrint (eLogWarning, "NetDbReq: No outbound tunnels");
 						}
 					}	
+					else
+					{
+						ret = false;
+						LogPrint (eLogWarning, "NetDbReq: Exploratory pool is not ready");
+					}	
+				}		
 			}
 			else
 			{