Using symlinks for bind mounts means we are not protecting an RO-mounted
layer against modification. Windows doesn't currently appear to offer a
better approach though, as we cannot create arbitrary empty WCOW scratch
layers at this time.
For windows-layer mounts, Unmount does not have access to the mounts
used to create it. So we store the relevant data in an Alternate Data
Stream on the mountpoint in order to be able to Unmount later.
Based on approach in https://github.com/containerd/containerd/pull/2366,
with sign-offs recorded as 'Based-on-work-by' trailers below.
This also partially-reverts some changes made in #6034 as they are not
needed with this mounting implmentation, which no longer needs to be
handled specially by the caller compared to non-Windows mounts.
Signed-off-by: Paul "TBBle" Hampson <Paul.Hampson@Pobox.com>
Based-on-work-by: Michael Crosby <crosbymichael@gmail.com>
Based-on-work-by: Darren Stahl <darst@microsoft.com>
The WCOW layer support does not support creating sandboxes with no
parent. Instead, parentless scratch layers must be layed out as a
directory containing only a directory named 'Files', and all data stored
inside 'Files'. At commit-time, this will be converted in-place into a
read-only layer suitable for use as a parent layer.
The WCOW layer support also does not deal with making read-only layers,
i.e. layers that are prepared to be parent layers, visible in a
read-only manner. A bind-mount or junction point cannot be made
read-only, so a view must instead be a small sandbox layer that we can
mount via WCOW, and discard later, to protect the layer against
accidental or deliberate modification.
Signed-off-by: Paul "TBBle" Hampson <Paul.Hampson@Pobox.com>
This is not really an error in most cases as most people do not use
devmapper, however this shows up as an error in the logs and in the
plugin service when querying the plugins.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
This is necessary so we can mount snapshots more than once with overlayfs,
otherwise mounts enter an unknown state.
related: https://github.com/moby/buildkit/pull/1100
Signed-off-by: Laura Brehm <laurabrehm@hey.com>
Co-authored-by: Zou Nengren <zouyee1989@gmail.com>
This error message currently does not provide useful information, because the `src` value that is interleaved will have been overridden by the call to `osi.ResolveSymbolicLink`. This stores the original `src` before the `osi.ResolveSymbolicLink` call so the error message can be useful.
Signed-off-by: June Rhodes <504826+hach-que@users.noreply.github.com>
In the CRI server initialization a syncgroup is setup that adds to the
counter for every cni config found/registered. This functions on platforms
where CNI is supported/theres an assumption that there will always be
the loopback config. However, on platforms like Darwin where there's generally
nothing registered the Wait() on the syncgroup returns immediately and the
channel used to return any Network config sync errors is closed. This channel
is one of three that's used to monitor if we should Close the CRI service in
containerd, so it's not great if this happens.
Signed-off-by: Danny Canter <danny@dcantah.dev>
