Fail to mount an iso unix-block device inside the container

Hello

I have a regular iso file in the lxd node mapped as a block with losetup as /dev/loop1.
I pass the iso to the containers as a unix-block device, specifying source /dev/loop1
The container is unprivileged

When I try to mount the block I get

mount: /root/mount: permission denied

I think I remember something regarding this issues, but I can’t seem to find it.

The kernel doesn’t allow unprivileged mounts except for a very limited set of filesystems (tmpfs, proc, sys, fuse).

Thanks for the info