Re: sshd does not die when client issues control-C or closes
From: Darren Tucker (dtucker_at_zip.com.au)
Date: Sat, 13 Mar 2004 08:28:17 +1100 To: firstname.lastname@example.org
Paul Myers wrote:
> The SSHD Version is 3.5 and I successfully logged in using password
OpenSSH 3.5 in an OpenBSD-only release. Do you mean 3.5p1? You should
consider using 3.7.1p2 or later because of a potential security issue:
> I am running an application which is sending IO to the connected PTY and
> allowing me to issue commands to another application. BUT I really do
> NOTHING except look at the hello world screen and hit Control-C.
> The Application dies, but the SSHD running under uClinux simply keeps
> running. The child processes die, but uClinux port of SSHD appears to be
> blissfully unaware of that. I am going through the code now to see why.
> There is no default child signal handler being used it appears when inetd
> runs sshd from under uClinux. There is one defined in the code but it is not
I suspect that another process is still holding a descriptor open and
sshd is waiting for it to close. Do you have "lsof" available?
Can you run sshd in debug mode ("sshd -ddd") and see what it says? (If
that changes the behaviour, crank LogLevel up to DEBUG in your config
and pull the messages out of your logs).
-- Darren Tucker (dtucker at zip.com.au) GPG key 8FF4FA69 / D9A3 86E9 7EEE AF4B B2D4 37C9 C982 80C7 8FF4 FA69 Good judgement comes with experience. Unfortunately, the experience usually comes from bad judgement.