nvr --serverlist: access denied

[erwin]

This is probably some silly misconfiguration on my part, but I've searched fairly extensively and haven't come up with a solution.

I've been using nvr for years to toggle settings across all instances of nvim.

Suddenly after years of working fine, I've noticed nvr --serverlist returns:

❯ nvr --serverlist
Access denied for nvim (5761)

Also strange enough, /proc/5761/environ is actually owned by 0:0 (root:root) instead of 1000:1000 as I would expect, even though PID 5761 itself is running as UID 1000. Zsh has the regular UID I would expect.

❯ ls -l /proc/5761/environ
-r-------- 1 root root 0 Jul  2 16:53 /proc/5761/environ
❯ ls -l /proc/$$/environ
-r-------- 1 me me 0 Jul  2 16:53 /proc/5407/environ

I'm running on Kubuntu 22.04.2 LTS x86_64.
NeoVim: NVIM v0.9.1

❯ nvr --version
nvr 2.5.1
pynvim 0.4.3
Python 3.10.6 (main, May 29 2023, 11:10:38) [GCC 11.3.0]

When inside of nvim I run:

echo v:servername

I get something like: /run/user/1000/nvim.15178.0

And if I check the permissions on that file, it seems fine:

❯ ll /run/user/1000/nvim.15178.0
srwxrwxr-x 1 me  me   0 Jul  2 17:09 /run/user/1000/nvim.15178.0=

I saw an article mentioning cap_ipc_lock could impact permissions in /proc/$PID, but I tried both setting and clearing the ipc_lock capability and I did not notice any change.

❯ sudo setcap cap_ipc_lock+ep ~/.local/share/neovim/bin/nvim
❯ sudo setcap -r $(which nvim)
❯ getcap $(which nvim)