bin/50695: ctrl-c in su password input breaks shell (bash, csh)

[coypu%sdf.org@localhost]

>Number:         50695
>Category:       bin
>Synopsis:       ctrl-c in su password input breaks shell (bash, csh)
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    bin-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sat Jan 23 11:05:00 +0000 2016
>Originator:     coypu
>Release:        7.99
>Organization:
>Environment:
NetBSD 7.99.25
>Description:
Using 'su' in terminal, if I use ctrl-c in password prompt, it will cause the terminal to stop producing newlines.

this happens in csh and bash (from pkgsrc), but not in other shells.
>How-To-Repeat:

>Fix: