opam broken on ubuntu 24.04 (bwrap: operation not permitted) #5968
Description
I've recently upgraded my computer from kubuntu 23.10 to kubuntu 24.04. This lead to errors with opam. Specifically, opam upgrade failed at trying to build the first package (dune.3.15.2), and opam switch create 4.14.1 also failed with the same error message:
bwrap: loopback: Failed RTM_NEWADDR: Operation not permitted
Doing some digging, it seems to be related to ubuntu deciding to restrict unprivileged user namespaces https://ubuntu.com/blog/ubuntu-23-10-restricted-unprivileged-user-namespaces. I found a fix, detailed here: https://etbe.coker.com.au/2024/04/24/ubuntu-24-04-bubblewrap/ which got opam working again.
Config:
<include here the output of `opam config report`, if applicable>
# opam config report
# opam-version 2.1.5
# self-upgrade no
# system arch=x86_64 os=linux os-distribution=ubuntu os-version=24.04
# solver builtin-mccs+glpk
# install-criteria -removed,-count[avoid-version,changed],-count[version-lag,request],-count[version-lag,changed],-count[missing-depexts,changed],-changed
# upgrade-criteria -removed,-count[avoid-version,changed],-count[version-lag,solution],-count[missing-depexts,changed],-new
# jobs 19
# repositories 2 (http) (default repo at 76de4586)
# pinned 1 (rsync)
# current-switch 4.14
# ocaml:native true
# ocaml:native-tools true
# ocaml:native-dynlink true
# ocaml:stubsdir /home/dorian/.opam/4.14/lib/ocaml/stublibs:/home/dorian/.opam/4.14/lib/ocaml
# ocaml:preinstalled false
# ocaml:compiler 4.14.1