RE: Does overlay driver work if built in to the kernel?

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



> -----Original Message-----
> From: Amir Goldstein <amir73il@xxxxxxxxx>
> Sent: Tuesday, September 20, 2022 11:50 PM
> To: Keyon Jie <yang.jie@xxxxxxxxxxxxxxx>
> Cc: Miklos Szeredi <miklos@xxxxxxxxxx>; overlayfs <linux-
> unionfs@xxxxxxxxxxxxxxx>; Jie, Keyon <keyon.jie@xxxxxxxxx>
> Subject: Re: Does overlay driver work if built in to the kernel?
> 
> On Wed, Sep 21, 2022 at 3:32 AM Keyon Jie <yang.jie@xxxxxxxxxxxxxxx>
> wrote:
> >
> > Hi all,
> >
> > I am new to the overlayfs, I am hitting issues to make kernel modules
> > work in a container environment where the Kubernetes feature really
> need
> > the overlayfs support.
> >
> > I figured out to make overlay driver built-in to the VM kernel (and then
> > shared to the container), but looks like the Kubernetes always fail when
> > trying to create overlayfs mounts, with errors like 'permission denied'.
> >
> 
> Usually, you want to look at the kernel log to see the reason for failure.
> That is likely because the container is "unprivileged"
> meaning not using the same uid 0 as the host.
> 
> Don't know which kernel you are running, but overlayfs can be mounted
> inside unprivileged container since kernel v5.11:
> 
> https://lore.kernel.org/linux-
> fsdevel/20201217142025.GB1236412@xxxxxxxxxxxxxxxxxxxxxxxxx/

Thank you Amir.
I am using v5.10 kernel, so looks I can try to backport some of the patches and try it again.
I assume take the 10-commits series from Miklos should be enough?
      vfs: move cap_convert_nscap() call into vfs_setxattr()
      vfs: verify source area in vfs_dedupe_file_range_one()
      ovl: check privs before decoding file handle
      ovl: make ioctl() safe
      ovl: simplify file splice
      ovl: user xattr
      ovl: do not fail when setting origin xattr
      ovl: do not fail because of O_NOATIME
      ovl: do not get metacopy for userxattr
      ovl: unprivieged mounts
https://lore.kernel.org/linux-fsdevel/1725e01a-4d4d-aecb-bad6-54aa220b4cd2@xxxxxxxxxxxxxxxxxxx/T/

Thanks,
~Keyon

> 
> >
> > I am seeing that overlay driver is released with modular
> > (CONFIG_OVERLAY_FS=m) in most (not sure if it is all) Linux
> > distributions, so I am wondering if the overlay driver work when built
> > in to the kernel?
> >
> 
> It can be built in or module.
> That seems unrelated to your problem.
> 
> Thanks,
> Amir.




[Index of Archives]     [Linux Filesystems Devel]     [Linux NFS]     [Linux NILFS]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux