exec/read -s bug?

[Lars Schneider]

Hi,

consider this script:

        #!/bin/bash
        [ "`whoami`" = "root" ] || {
          exec sudo -u root "$0" "$@"
        }
        read -s -p "enter stuff: " stuff

If I run the script as normal user (not root!) and I abort the "read -s -p"
call with "ctrl-c", then my shell is still in silent mode.

I can consitently replicate that behavior on Ubuntu 14.04.5 LTS (Trusty) 
and BASH 4.3.11(1)-release (x86_64-pc-linux-gnu) as well as BASH 4.3.30.

I also installed BASH 4.4.18 from source and I can replicate the issue.

Can you replicate the issue? 
Is this a known issue?
Do you consider it a bug? 
How would you investigate that further? 
Do you see a workaround for the problem?

I briefly looked into the `builtins/exec.def` and `builtins/read.def` code
and my impression is that `exec` might mess with the `ttsave/ttyrestore` 
stack.

Thanks,
Lars


PS: Before I reached out on the bug bash mailing list I asked for help here:
https://unix.stackexchange.com/questions/463253/why-would-read-s-behaves-differently-than-read-if-killed-with-ctrl-c
 
<https://unix.stackexchange.com/questions/463253/why-would-read-s-behaves-differently-than-read-if-killed-with-ctrl-c>