[Virtual-pkg-base-maintainers] Bug#726567: base: same pty allocated to multiple processes

[Kris Coward]

Package: base
Severity: important

Dear Maintainer,

I have a screen session running on my machine so that I can ssh in (or mosh
in) and reattach to it from an assortment of remote machines.

Recently, when connecting from my phone (and android running connectbot),
attempts to reattach to the screen (i.e. screen -d -r as the first command
upon login) get the error message:

Attaching from inside of screen?

Since the error message is bogus, I ran tty and got:

/dev/pts/2

Running ps x to see if this tty is already allocated, I can see one of the
processed inside screen is already using it:

27608 pts/2    Ss+    0:00 vi /home/kris/web/unripe/schedule.html


Not knowing whether this is a bug in screen, in sshd, or in the kernel,
(e.g. is screen using the tty without identifying it as in use, or
releasing it while still in use, or is the kernel doling out ttys that
it knows are already in use, or is sshd grabbing an in-use tty--or maybe
something else entirely is involved), I've reported it as a bug in base.

Oddly, this error only arises when I connect from my phone, using
connectbot (v1.7.1 2010.10.08 on an SGH-T839 with 2.2.1 firmware).
Applying Postel's Law, I'm inclined to believe this means that both
connectbot and something on the server are buggy.

I'd really appreciate a fix.

Thanks,
Kris

-- System Information:
Debian Release: 7.1
  APT prefers stable
  APT policy: (500, 'stable')
Architecture: amd64 (x86_64)

Kernel: Linux 3.2.0-4-amd64 (SMP w/8 CPU cores)
Locale: LANG=en_CA.UTF-8, LC_CTYPE=en_CA.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash