[v5.1] Always chown volumes when mounting into a container #22790
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
When an empty volume is mounted into a container, Docker will chown that volume appropriately for use in the container. Podman does this as well, but there are differences in the details. In Podman, a chown is presently a one-and-done deal; in Docker, it will continue so long as the volume remains empty. Mount into a dozen containers, but never add content, the chown occurs every time. The chown is also linked to copy-up; it will always occur when a copy-up occurred, despite the volume now not being empty. This PR changes our logic to (mostly) match Docker's. For some reason, the chowning also stops if the volume is chowned to root at any point. This feels like a Docker bug, but as they say, bug for bug compatible. In retrospect, using bools for NeedsChown and NeedsCopyUp was a mistake. Docker isn't actually tracking this stuff; they're just doing a copy-up and permissions change unconditionally as long as the volume is empty. They also have the two linked as one operation, seemingly, despite happening at very different times during container init. Replicating that in our stateful system is nontrivial, hence the need for the new CopiedUp field. Basically, we never want to chown a volume with contents in it, except if that data is a result of a copy-up that resulted from mounting into the current container. Tracking who did the copy-up is the easiest way to do this. Fixes containers#22571 Signed-off-by: Matthew Heon <[email protected]>
|
[APPROVALNOTIFIER] This PR is APPROVED This pull-request has been approved by: Luap99, openshift-cherrypick-robot The full list of commands accepted by this bot can be found here. The pull request process is described here
Needs approval from an approver in each of these files:
Approvers can indicate their approval by writing |
openshift-ci
bot
added
the
approved
openshift-merge-bot
bot
merged commit 4d0cd1b
into
containers:v5.1
86 of 87 checks passed
stale-locking-app
bot
added
the
locked - please file new issue/PR
Sign up for free
to subscribe to this conversation on GitHub.
Already have an account?
Sign in.
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
This is an automated cherry-pick of #22727
/assign mheon