Dropbear turns into zombie process after killing

[Matt Johnston]

On Thu, Nov 20, 2008 at 04:54:14PM +0100, Jeroen van der Vegt wrote:
> Hello,
> 
> 
> We're using Dropbear 0.51 to create a tunnel from an embedded ARM device to
> a server (running openSSH). We use the precompiled dropbear version from
> Debian, and ssh is symlinked to dbclient.
> The tunnel is constructed in a script using this command:
> 
> 	# ssh -i /etc/dropbear/dropbear_rsa_host_key $USER@$REMOTEHOST -L \
> 		$LOCALPORT:127.0.0.1:$REMOTEPORT -f -N
> 
> A tunnel created this way works fine. When the script is done, the tunnel
> should be removed. We simply kill all instances of 'ssh' for this.
> Unfortunately, this results in a zombie dropbear process on our ARM device.

How are you running that command? Cleaning up zombie
processes is the responsibility of the parent process that
spawns a process (using waitpid() etc, most shells etc would
take care of it). I don't think there's much that the
Dropbear client could be doing (or not doing) that would
influence whether it's zombified?

Matt