Bug#397339: it's not really a bug
This problem is not related to the "checkwinsize" function from bash ?
You can read this in the bash FAQ , Section E11 :
E11) If I resize my xterm while another program is running, why doesn't
bash notice the change?
This is another issue that deals with job control.
The kernel maintains a notion of a current terminal process group.
Members of this process group (processes whose process group ID is equal
to the current terminal process group ID) receive terminal-generated
signals like SIGWINCH. (For more details, see the JOB CONTROL section
of the bash man page.)
If a terminal is resized, the kernel sends SIGWINCH to each member of
the terminal's current process group (the `foreground' process group).
When bash is running with job control enabled, each pipeline (which may
be a single command) is run in its own process group, different from
bash's process group. This foreground process group receives the
SIGWINCH; bash does not. Bash has no way of knowing that the terminal
has been resized.
There is a `checkwinsize' option, settable with the `shopt' builtin,
that will cause bash to check the window size and adjust its idea of the
terminal's dimensions each time a process stops or exits and returns
control of the terminal to bash. Enable it with `shopt -s checkwinsize'.
I think you can closed this bug open against openssh-client package.