Accessing S3 remotes via Podman container?

[seannymurrs]

I have an S3-compatible remote mounted locally using rclone mount. I'm trying to run a container of Audiobookshelf via Podman, but the container is unable to access my locally mounted directory. I did some searching, and I've found a few posts mentioning compatibility issues between S3 and Podman, but I can't find specifics on whether there are ways to workaround this issue.

[rhatdan]

What error are you seeing? Could be SELinux or User Namespace blocking access.

Is the HomeDir local?

[eriksjolund]

I did some experimenting with FUSE and squashfs and noticed that

arguments to podman run	result	output
--user 0:0	success	total 0
--user=1000:1000	failure	ls: cannot access '/ctr/mntdir/ubuntu': Permission denied
--user=1000:1000 --userns=keep-id:uid=1000,gid=1000	success	total 0

All the details

Click me

1. mkdir ~/squashctr
2. cd ~/squashctr
3. Create file ~/squashctr/Containerfile containing

   FROM ubuntu
   RUN apt-get update ; apt-get install -y squashfs-tools
   RUN mksquashfs /home /ubuntu.squash
   

4. podman build -t squash .
5. podman run --rm --name tmpctr --detach localhost/squash sleep 200
6. podman cp tmpctr:/ubuntu.squash .
7. mkdir mntdir
8. squashfuse ubuntu.squash mntdir
9. id -u
   The following output is printed

   1210
   

10. id -g
    The following output is printed

    1210
    

11. Run command

    podman run --rm --security-opt label=disable \
           --user=0:0 \
           -v /home/test711/squashctr/:/ctr ubuntu ls -l 
    

    The following output is printed

    total 0
    

12. Run command

     podman run --rm --security-opt label=disable \
            --user=1000:1000 \
            -v /home/test711/squashctr/:/ctr ubuntu ls -l 
    

    The following output is printed

    ls: cannot access '/ctr/mntdir/ubuntu': Permission denied
    

13. Run command

    podman run --rm --security-opt label=disable \
            --user=1000:1000 --userns=keep-id:uid=1000,gid=1000  \:
            -v /home/test711/squashctr/:/ctr ubuntu ls -l 
    

    The following output is printed

    total 0
    

I somehow get the impression that --user $uid:$gid needs --userns keep-id:uid=${uid},${gid} when $uid and $gid are positive.
(I haven't fully understood how all this works)

@seannymurrs Maybe you need to add --userns keep-id:uid=${uid},${gid}?