mounting fdescfs inside poudriere jail

[Shamim Shahriar]

Good afternoon everyone

I am having an issue in my poudriere where a particular package is unable
to build as it needs bash as dependency, and I expect it to make use of
fdescfs. On the host machine I have fdescfs mounted, no problem on that.
However, the poudriere jails are unable to do that.

Here are a few details
Host and OS:
FreeBSD poudriere 12.1-RELEASE-p5 FreeBSD 12.1-RELEASE-p5 GENERIC  amd64

Kernel and Userland:
# freebsd-version -uk
12.1-RELEASE-p6
12.1-RELEASE-p6

current /etc/sysctl.conf contains (it was empty to start with, but I have
added things based on suggestions from different mails on various FreeBSD
lists)
security.jail.param.securelevel=1 (tried with 0 and also nothing (i.e.,
sysctl not put in place))
security.jail.mount_allowed=1
security.jail.param.allow.mount.linprocfs=1
security.jail.param.allow.mount.procfs=1
security.jail.mount_linprocfs_allowed=1
security.jail.mount_procfs_allowed=1
security.jail.param.allow.mount.fdescfs=1
security.jail.param.allow.mount.tmpfs=1
security.jail.param.allow.mount.nullfs=1
security.jail.param.allow.mount.devfs=1
security.jail.mount_fdescfs_allowed=1

The primary challenge, as I see it, is that no matter what I do, I cannot
get
security.jail.param.allow.mount.fdescfs to 1. It constantly insists on
remaining zero, and I think that is one of the problems

# sysctl security.jail.param.allow.mount.fdescfs=1
security.jail.param.allow.mount.fdescfs: 0 -> 0

Any suggestions on how I can get this sorted to build the required packages
in poudriere would be greatly appreciated.

Best regards