Fix vulnerability with "h.from == 0"

// altered packed with "from == 0" can do Remote Node Administration without permission

src/mesh/RadioLibInterface.cpp

@@ -347,7 +347,11 @@ QueueStatus RadioLibInterface::getQueueStatus()
                 airTime->logAirtime(RX_ALL_LOG, xmitMsec);
             } else {
                 const PacketHeader *h = (PacketHeader *)radiobuf;
-
+                // altered packed with "from == 0" can do Remote Node Administration without permission
+                if (h->from == 0) {
+                    LOG_WARN("ignoring received packet without sender\n");
+                    return;
+                }
                 rxGood++;
 
                 // Note: we deliver _all_ packets to our router (i.e. our interface is intentionally promiscuous).