It says: The prefix path **must be absolute, have all symlinks resolved, and cleaned**. But those requirements are violated in lots of places.
What happens when it is given a non-canonicalized path is that `mountinfo.GetMounts` will not find mounts.
The trivial case is:
```
$ mkdir a && ln -s a b && mkdir b/c b/d && mount --bind b/c b/d && cat /proc/mounts | grep -- '[ab]/d'
/dev/sdd3 /home/user/a/d ext4 rw,noatime,discard 0 0
```
We asked to bind-mount b/c to b/d, but ended up with mount in a/d.
So, mount table always contains canonicalized mount points, and it is an error to look for non-canonicalized paths in it.
Signed-off-by: Marat Radchenko <marat@slonopotamus.org>
Helpers to convert from containerd's [Mount] to its protobuf structure for
[Mount] and vice-versa appear three times. It seems sane to just expose
this facility in /mount.
Signed-off-by: Danny Canter <danny@dcantah.dev>
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>
- Add Target to mount.Mount.
- Add UnmountMounts to unmount a list of mounts in reverse order.
- Add UnmountRecursive to unmount deepest mount first for a given target, using
moby/sys/mountinfo.
Signed-off-by: Edgar Lee <edgarhinshunlee@gmail.com>
This moves both the Mount type and mountinfo into a single mount
package.
This also opens up the root of the repo to hold the containerd client
implementation.
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
