Re: chpst -u -/ "unable to get password/group file entry"

[David Miller <dave@frop.net>]

Indeed it was looking for the libnss libraries and /etc/nsswitch.conf as Jack suspected. Mike's td.py script didn't find the nss library dependency, neither does ldd.

Looking at the source and the strace, the chroot happens before the suidgid. And the uid/gid is looked up at the same time as the suidgid. I just wasn't expecting it to work this way.

the -U workaround seems to do the trick, Thanks paul.

Paul spoke thusly:
> David Miller <dave@frop.net> wrote:
> > I wonder if you could give me some pointers on how to use strace and
> > what to look for. I'm not very familiar with it
> 
> You don't need to copy strace into the chroot area.  Just run:
> strace chpst -u dave -/ chroot /ls
> 
> strace will output a lot of information, but the interesting bit will
> be near the end.  Just before the error message appears, you should
> see one of more failed open() calls.  That will tell you what files
> are missing.
> 
> Or you could work around the problem like this:
> chpst -U dave sh -c 'exec chpst -u ":$UID:$GID" -/ chroot /ls'
> 
> > Shouldn''t chpst look up the uid and gid for -u before the chroot
> > happens?
> 
> That's probably a good idea, but in fact it doesn't do that.
> 
> 
> paul