[Bug 2573] dead sessions cannot be closed with ~.

bugzilla-daemon at bugzilla.mindrot.org bugzilla-daemon at bugzilla.mindrot.org
Fri Aug 18 11:45:08 AEST 2017


https://bugzilla.mindrot.org/show_bug.cgi?id=2573

--- Comment #7 from Darren Tucker <dtucker at zip.com.au> ---

(In reply to Christoph Anton Mitterer from comment #6)
[...]

This is the clue: it's stuck in rekeying:

I was able to reproduce with:
$ ssh -o rekeylimit="1G 15s" -vvv server
$ sudo kill -STOP [sshd_pid]

> debug1: SSH2_MSG_KEXINIT sent
> debug1: rekeying in progress

[...]
> select(7, [3], [], NULL, {tv_sec=15, tv_usec=0}

FD#3 is almost certainly the socket to the server, and stdin is not
checked.

The reason for this is in client_wait_until_can_do_something() ->
channel_prepare_select():

        if (!rekeying)
                channel_handler(channel_pre, *readsetp, *writesetp,
                    minwait_secs);

so while it's rekeying it won't process stdin and thus doesn't look for
escape sequences.  I'm not sure what do to about it, though.

In the mean time, you could mitigate by increasing or turning of
rekeying on the affected connection.

-- 
You are receiving this mail because:
You are watching the assignee of the bug.
You are watching someone on the CC list of the bug.


More information about the openssh-bugs mailing list