Re: ssh going zombie

From: Peter Childs (dp_at_expressnationalcarriers.co.uk)
Date: 05/04/05

  • Next message: Christ, Bryan: "AES Vulnerability" 
    Date: Wed, 04 May 2005 20:59:06 +0100
To: Robert L Sowders <rsowders@usgs.gov>

    Robert L Sowders wrote:

    >on the server kill the ssh server then restart it with the -d flag to put
    >it into debug mode. This process will not fork and will write all debug
    >output to the stderr (the window you started it from), then connect with
    >winscp and try to duplicate the error you reported.
    >
    >it should give you some clues as to what is happening.
    >
    >rls
    >
    >
    >
    >
    >
    >Peter Childs <dp@expressnationalcarriers.co.uk>
    >04/28/2005 08:56 PM
    >
    >
    > To: secureshell@securityfocus.com
    > cc:
    > Subject: ssh going zombie
    >
    >
    > Using sshd under Debian Unstable Openssh 0.9.7e
    >
    > When winscp disconnects from our server the scp process goes zombie
    >and the ssh process hogs the processor on the server. This only seams
    >to happern with winscp and not with scp or ssh under linux. If the
    >subprocess is removed from the sshd config file the a sub sshd process
    >goes zombie instead and the calling sshd process hogs the processor.
    >
    > I'm think it may have somthing to do with the way winscp talks to
    >sshd , but the winscp people seam to think this is a problem with sshd.
    >I get this feeling this is going to be a problem nobody has a clue on
    >and wishes to blame the other party.
    >
    >
    >Peter Childs
    >
    >
    >
    >
    >
    >
    >
        Ok after installing ssh 4.0 from source I've fixed the problem. It
    seams that 3.8 which is on debian sarge has a bug when it uses
    sftp-server in that it does not wait for the process to end and then
    hogs the processor.

    Peter CHilds

  • Next message: Christ, Bryan: "AES Vulnerability"

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