fix crash in AdminCommandconnection::TLSSensingCallback

Summary: Function was missing a return after handling an error which could lead to use after free

Reviewed By: MohamedBassem

Differential Revision: D17907011

fbshipit-source-id: fccfece467e27b987b733272c02fe9a8caf4925e

logdevice/server/admincommands/CommandListener.cpp

@@ -52,6 +52,7 @@ void AdminCommandConnection::TLSSensingCallback::getReadBuffer(
   if (rv != 1) {
     ld_critical("There is no 1 byte in the socket for TLS detection.");
     connection_.closeConnectionAndDestroyObject();
+    return;
   }
 
   ld_debug("read data is available for peeking");