tree de5a87972b384ed64084d42c49233f3292dc653c
parent 2d90611cb06b780b165296aa3abd1f7229d503f9
author Neels Hofmeyr <neels@hofmeyr.de> 1567116926 +0200
committer Neels Hofmeyr <neels@hofmeyr.de> 1567118281 +0200

fix: vty crash by logging during VTY_CLOSED event handling

When a VTY closes, dispatch the VTY_CLOSED signal before tearing down the VTY
buffer and fd.

In particular this fixes:

- a crash during telnet_close_client(), invoked by the VTY_CLOSED event, which
  logs to DLGLOBAL and uses vty->obuf that, so far, vty_close() had already
  unallocated earlier (OS#4164).

- the logging about closing a telnet session so far logged:
    DLGLOBAL INFO Closing telnet connection r=NULL<->l=NULL
  By dispatching the VTY_CLOSED event while the fd is still valid, we instead
  get the actual connection IP address and port being closed:
    DLGLOBAL INFO Closing telnet connection r=127.0.0.1:36708<->l=127.0.0.1:4258

Related: OS#4164
Change-Id: I1d235cbfbfb9aaf411316642c7bcfac12106df44