Re: Surprise null root password

On Tue, May 30, 2023 at 8:36 AM bob prohaska <fbsd@www.zefox.net> wrote:
>
> On Tue, May 30, 2023 at 08:41:33AM +0200, Alexander Leidinger wrote:
> >
> > Quoting bob prohaska <fbsd@www.zefox.net> (from Fri, 26 May 2023 16:26:06
> > -0700):
> >
> > > On Fri, May 26, 2023 at 10:55:49PM +0200, Yuri wrote:
> > > >
> > > > The question is how you update the configuration files,
> > > > mergemaster/etcupdate/something else?
> > > >
> > >
> > > Via etcupdate after installworld. In the event the system
> > > requests manual intervention I accept "theirs all". It seems
> > > odd if that can null a root password.
> > >
> > > Still, it does seem an outside possibility. I could see it adding
> > > system users, but messing with root's existing password seems a
> > > bit unexpected.
> >
> > As you are posting to -current@, I expect you to report this issue about
> > 14-current systems. As such: there was a "recent" change (2021-10-20) to the
> > root entry to change the shell.
> > https://cgit.freebsd.org/src/commit/etc/master.passwd?id=d410b585b6f00a26c2de7724d6576a3ea7d548b7
> >
> > By blindly accepting all changes, this has reset the PW to the default
> > setting (empty).
>
> So it's a line-by-line merge. That's the most sensible explanation available.
>
> >
> > I suggest to review changes ("df" instead of "tf" in etcupdate) to at least
> > those files which you know you have modified, including the password/group
> > stuff. After that you can decide if the diff which is shown with "df" can be
> > applied ("tf"), or if you want to keep the old version ("mf"), or if you
> > want to modify the current file ("e", with both versions present in the file
> > so that you can copy/paste between the different versions and keep what you
> > need).
> >
>
> The key sequences required to copy and paste between files in the edit screen
> were elusive. Probably it was thought self-evident, but not for me. I last tried
> it long ago, via mergemaster. Is there is a guide to commands for merging files
> using /etcupdate? Is it in the vi man page? I couldn't find it.
>
> Thanks for writing!
>
> bob prohaska
>
>

It's been a while for me so I forget if etcupdate resolve is automatic
or there is a prompt or message about it, but the guide at
https://docs.freebsd.org/en/books/handbook/cutting-edge/#updating-src-completing-merge-etcupdate
says:
If etcupdate(8) is not able to merge a file automatically, the merge
conflicts can be resolved with manual interaction by issuing:
# etcupdate resolve

But this info is far below the steps at
https://docs.freebsd.org/en/books/handbook/cutting-edge/#updating-src-quick-start
with section 25.6.6.1 also not being mentioned in the steps.

Info on merge commands, regardless, is under the Resolve Mode
description in the etcupdate man page
https://man.freebsd.org/cgi/man.cgi?etcupdate.