* login/telnet problems
@ 2013-01-30 11:41 Henrik Grindal Bakken
2013-02-01 16:31 ` Karel Zak
0 siblings, 1 reply; 3+ messages in thread
From: Henrik Grindal Bakken @ 2013-01-30 11:41 UTC (permalink / raw)
To: util-linux
Hi. I'm working on a product which (sadly) requires telnet, and after
an upgrade from util-linux-2.20 to 2.22.2, telnet starts acting up by
dropping the first character (at least that's the easiest problem to
spot).
I looked around, and determined that the problem was related to
upgrading login(1). Further, I bisected util-linux, and determined
that the problem was introduced by:
commit 2e7035646eb85851171cc2e989bfa858a4f00cd4
Author: Karel Zak <kzak@redhat.com>
Date: Thu Jul 12 16:33:52 2012 +0200
login: close tty before vhangup()
Let's close all tty file descriptors before vhangup() call.
References: https://lkml.org/lkml/2012/6/5/145
Signed-off-by: Karel Zak <kzak@redhat.com>
I reverted that commit locally, and telnet started working nicely
again. This is netkit-telnet-0.17, btw.
It's not a huge problem for me to keep a local revert of this commit,
but I thought perhaps you wanted to know it did actually break
something (although one can argue the very existence of telnet these
days is a bug...).
--
Henrik Grindal Bakken <hgb@ifi.uio.no>
PGP ID: 8D436E52
Fingerprint: 131D 9590 F0CF 47EF 7963 02AF 9236 D25A 8D43 6E52
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: login/telnet problems
2013-01-30 11:41 login/telnet problems Henrik Grindal Bakken
@ 2013-02-01 16:31 ` Karel Zak
2013-02-01 17:29 ` Henrik Grindal Bakken
0 siblings, 1 reply; 3+ messages in thread
From: Karel Zak @ 2013-02-01 16:31 UTC (permalink / raw)
To: Henrik Grindal Bakken; +Cc: util-linux
On Wed, Jan 30, 2013 at 12:41:52PM +0100, Henrik Grindal Bakken wrote:
> Hi. I'm working on a product which (sadly) requires telnet, and after
> an upgrade from util-linux-2.20 to 2.22.2, telnet starts acting up by
> dropping the first character (at least that's the easiest problem to
> spot).
Seems like a kernel problem: https://lkml.org/lkml/2013/1/15/641
> It's not a huge problem for me to keep a local revert of this commit,
> but I thought perhaps you wanted to know it did actually break
> something (although one can argue the very existence of telnet these
> days is a bug...).
In https://bugzilla.redhat.com/show_bug.cgi?id=904182 someone
suggested -D for telned as workaround :-)
Karel
--
Karel Zak <kzak@redhat.com>
http://karelzak.blogspot.com
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: login/telnet problems
2013-02-01 16:31 ` Karel Zak
@ 2013-02-01 17:29 ` Henrik Grindal Bakken
0 siblings, 0 replies; 3+ messages in thread
From: Henrik Grindal Bakken @ 2013-02-01 17:29 UTC (permalink / raw)
To: Karel Zak; +Cc: util-linux
Karel Zak <kzak@redhat.com> writes:
> On Wed, Jan 30, 2013 at 12:41:52PM +0100, Henrik Grindal Bakken wrote:
>> Hi. I'm working on a product which (sadly) requires telnet, and after
>> an upgrade from util-linux-2.20 to 2.22.2, telnet starts acting up by
>> dropping the first character (at least that's the easiest problem to
>> spot).
>
> Seems like a kernel problem: https://lkml.org/lkml/2013/1/15/641
How fascinating! It didn't even remotely occur to me that a (seemingly)
login/telnet problem was kernel-related...
>> It's not a huge problem for me to keep a local revert of this commit,
>> but I thought perhaps you wanted to know it did actually break
>> something (although one can argue the very existence of telnet these
>> days is a bug...).
>
> In https://bugzilla.redhat.com/show_bug.cgi?id=904182 someone
> suggested -D for telned as workaround :-)
Hmm. I'll stick with my util-linux patch for now, I think. I'll follow
the development on the kernel bug, though. Thanks a bunch.
I actually tried using different -D options to telnet, and noticing that
some of them actually fixed the problem, but that gave me debug output
on the telnet client, which wasn't really acceptable...
--
Henrik Grindal Bakken <hgb@ifi.uio.no>
PGP ID: 8D436E52
Fingerprint: 131D 9590 F0CF 47EF 7963 02AF 9236 D25A 8D43 6E52
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2013-02-01 17:29 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2013-01-30 11:41 login/telnet problems Henrik Grindal Bakken
2013-02-01 16:31 ` Karel Zak
2013-02-01 17:29 ` Henrik Grindal Bakken
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox