access denied in docker when mounting volumes while userns is enabled - linux

Question

I am trying to use docker's user namespaces feature using the official documentation here
I have added the configuration to my daemon.json file like
{
"debug":true,
"experimental": false,
"features":{"buildkit": false},
"userns-remap":"default"
}
I also verified that both subuid and subguid in /etc contain the following entries
dhost:100000:65536
dockremap:165536:65536
I built my image to verify the functionality using an alpine:latest like so
FROM alpine:latest
RUN mkdir -p /root/.cache
WORKDIR /app
command used in building the image docker image build -t myimage:1 .
Then I run a container from this image using
docker container run -it --rm --name mycontainer -v "$(pwd)/test:/app" myimage:1 sh
I get access to the workdir inside the container (app) but I cannot touch/create any file without getting permission denied. Do I need to change the owner of the test directory I used to mount? if yes, who should own it?
docker version
docker version
Client: Docker Engine - Community
Version: 20.10.14
API version: 1.41
Go version: go1.16.15
Git commit: a224086
Built: Thu Mar 24 01:47:57 2022
OS/Arch: linux/amd64
Context: default
Experimental: true
Server: Docker Engine - Community
Engine:
Version: 20.10.14
API version: 1.41 (minimum version 1.12)
Go version: go1.16.15
Git commit: 87a90dc
Built: Thu Mar 24 01:45:46 2022
OS/Arch: linux/amd64
Experimental: false
containerd:
Version: 1.5.11
GitCommit: 3df54a852345ae127d1fa3092b95168e4a88e2f8
runc:
Version: 1.0.3
GitCommit: v1.0.3-0-gf46b6ba
docker-init:
Version: 0.19.0
GitCommit: de40ad0
Host OS info
lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 18.04.6 LTS
Release: 18.04
Codename: bionic