[Buildroot] Dropbear remote login fails

[Buildroot] Dropbear remote login fails

[Petr Kulhavy]

Hi,

recently I upgraded my system to the latest version of buildroot. After 
that I noticed that I cannot any longer ssh on my device because the 
default shell /bin/sh for the root is not in /etc/shells.

Shouldn't it be added there? Or have I misconfigured something?

Thanks
Petr

[Buildroot] Dropbear remote login fails

[Peter Korsgaard]

>>>>> "Petr" == Petr Kulhavy <brain@jikos.cz> writes:

 > Hi,
 > recently I upgraded my system to the latest version of
 > buildroot. After that I noticed that I cannot any longer ssh on my
 > device because the default shell /bin/sh for the root is not in
 > /etc/shells.

 > Shouldn't it be added there? Or have I misconfigured something?

With 'upgraded' do you mean you are using git head and not
E.G. 2017.11.2?

We recently had a patch changing this for bash:

commit 4d279697afbf8fb295274784103be2b837113d5e
Author: Romain Naour <romain.naour@smile.fr>
Date:   Sat Jan 13 17:05:27 2018 +0100

    package/bash: add /bin/bash to /etc/shells

    When bash is selected, /bin/bash is not added to /etc/shells
    (see man shells). So, login tools like dropbear reject the ssh
    connexions for users using bash as shell in /etc/passwd.

    buildroot authpriv.warn dropbear[853]: User 'kubu' has invalid shell, rejected

    Reported-by: Jeremy Rosen <jeremy.rosen@smile.fr>
    Signed-off-by: Romain Naour <romain.naour@smile.fr>
    Cc: "Yann E. MORIN" <yann.morin.1998@free.fr>
    Acked-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
    Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

This has the side effect of adding an /etc/shells file to your rootfs
where we didn't use to have one (and libc falls back to /bin/sh +
/bin/csh if /etc/shells doesn't exist), so if you have bash enabled then
/bin/sh is no longer accepted.

There's a patch series pending in patchwork fixing this. It would be
great if you could give it a test:

http://patchwork.ozlabs.org/project/buildroot/list/?series=24357

-- 
Bye, Peter Korsgaard

[Buildroot] Dropbear remote login fails

[Petr Kulhavy]

On 26/01/18 14:54, Peter Korsgaard wrote:
>>>>>> "Petr" == Petr Kulhavy <brain@jikos.cz> writes:
>   > Hi,
>   > recently I upgraded my system to the latest version of
>   > buildroot. After that I noticed that I cannot any longer ssh on my
>   > device because the default shell /bin/sh for the root is not in
>   > /etc/shells.
>
>   > Shouldn't it be added there? Or have I misconfigured something?
>
> With 'upgraded' do you mean you are using git head and not
> E.G. 2017.11.2?
Yes, I'm using the head now.

>
> We recently had a patch changing this for bash:
>
> commit 4d279697afbf8fb295274784103be2b837113d5e
> Author: Romain Naour <romain.naour@smile.fr>
> Date:   Sat Jan 13 17:05:27 2018 +0100
>
>      package/bash: add /bin/bash to /etc/shells
>
>      When bash is selected, /bin/bash is not added to /etc/shells
>      (see man shells). So, login tools like dropbear reject the ssh
>      connexions for users using bash as shell in /etc/passwd.
>
>      buildroot authpriv.warn dropbear[853]: User 'kubu' has invalid shell, rejected
>
>      Reported-by: Jeremy Rosen <jeremy.rosen@smile.fr>
>      Signed-off-by: Romain Naour <romain.naour@smile.fr>
>      Cc: "Yann E. MORIN" <yann.morin.1998@free.fr>
>      Acked-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
>      Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
>
> This has the side effect of adding an /etc/shells file to your rootfs
> where we didn't use to have one (and libc falls back to /bin/sh +
> /bin/csh if /etc/shells doesn't exist), so if you have bash enabled then
> /bin/sh is no longer accepted.
Ah, that explains why it worked before! I do have bash enabled as well.

> There's a patch series pending in patchwork fixing this. It would be
> great if you could give it a test:
>
> http://patchwork.ozlabs.org/project/buildroot/list/?series=24357
I will give it a try.

Petr