How do I mount a file on top of a broken symbolic link?

Question

In preparation of a chroot I'm doing an mount --bind /etc/resolv.conf ${MOUNTPOINT}/etc/resolv.conf. I need this because the ${MOUNTPOINT} contains a broken etc/resolv.conf.

However, mount is missing the point of the operation. It complains that ${MOUNTPOINT}/etc/resolv.conf "is a symbolic link to nowhere". Yes, I know. That's why I'm doing the rebind in the first place.

[edit] By request, /etc/resolv.conf is a normal file:

-rw-r--r-- 1 root root 42 Feb 6 12:52 /etc/resolv.conf

with normal content

nameserver 192.168.4.1

This should also be used after the chroot, but not by changing the actual ${MOUNTPOINT}/etc/resolv.conf. That should remain as-is:

lrwxrwxrwx 1 root root 27 Jun 14 2017 ${MOUNTPOINT}/etc/resolv.conf -> /run/resolvconf/resolv.conf

(Background: I know about rebinding /run/ in the context of resolv.conf. Doesn't work for me, /etc/resolv.conf is a real file and not a symbolic link. It's only ${MOUNTPOINT}/etc/resolv.conf that's broken, and it's only broken during the chroot so I can't just overwrite it).

I honestly got lot. Would you add `la -la /etc/resolv.conf` output to the question? — Rui F Ribeiro, Mar 12 '18 at 12:50
@RuiFRibeiro: Are you aware of bind mounts, especially for files? They are a tad obscure, I know. — MSalters, Mar 12 '18 at 12:51
I only have used it to mount directories. resolvconf/dnsmask might be getting in your way, and I would not use any of them in a server setting. — Rui F Ribeiro, Mar 12 '18 at 12:53
@RuiFRibeiro: resolvconf is indeed getting in my way during the `chroot`. That's what I'm trying to avoid here. — MSalters, Mar 12 '18 at 12:58
@Kiwy: Because the challenge is not to touch the link. After I'm done with the `chroot` and have umounted everything, the link should be untouched. — MSalters, Mar 12 '18 at 13:35
[...good luck !](https://unix.stackexchange.com/a/395458/22142) — don_crissti, Mar 12 '18 at 13:44
@don_crissti: That's the _source_. In my case, the symlink merely happens to be in the place where the bind hides it. But as we know from regular directories used as mount points, Unix & Linux have no problem hiding stuff underneath a mount. — MSalters, Mar 12 '18 at 13:54
The point was that when using `mount` the paths are resolved first (source _and_ destination)... and in your case the destination can't be resolved. — don_crissti, Mar 12 '18 at 13:55
@GAD3R: See question and previous comments. The challenge is NOT to alter the actual file system. — MSalters, Mar 12 '18 at 14:32

How do I mount a file on top of a broken symbolic link?

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