Re: sshd does not die when client issues control-C or closes

From: Darren Tucker (dtucker_at_zip.com.au)
Date: 03/12/04

  • Next message: Milen Minev: "Re: Automatic ssh connections" 
    Date: Sat, 13 Mar 2004 08:28:17 +1100
To: pmyers@spectracomcorp.com

    Paul Myers wrote:

    > The SSHD Version is 3.5 and I successfully logged in using password
    > authentication.

    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:
    http://www.openssh.com/txt/buffer.adv

    > 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
    > used.

    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.
  • Next message: Milen Minev: "Re: Automatic ssh connections"

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