Functions `GetMounts()` and `parseMountTable()` return all the entries
as read and parsed from /proc/self/mountinfo. In many cases the caller
is only interested only one or a few entries, not all of them.
One good example is `Mounted()` function, which looks for a specific
entry only. Another example is `RecursiveUnmount()` which is only
interested in mount under a specific path.
This commit adds `filter` argument to `GetMounts()` to implement
two things:
1. filter out entries a caller is not interested in
2. stop processing if a caller is found what it wanted
`nil` can be passed to get a backward-compatible behavior, i.e. return
all the entries.
A few filters are implemented:
- `PrefixFilter`: filters out all entries not under `prefix`
- `SingleEntryFilter`: looks for a specific entry
Finally, `Mounted()` is modified to use `SingleEntryFilter()`, and
`RecursiveUnmount()` is using `PrefixFilter()`.
Unit tests are added to check filters are working.
[v2: ditch NoFilter, use nil]
[v3: ditch GetMountsFiltered()]
[v4: add unit test for filters]
[v5: switch to gotestyourself]
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Upstream-commit: bb934c6aca3e77541dd4fd51b9ab2706294dadda
Component: engine
commit 617c352e9225 "Don't create devices if in a user namespace"
introduced check, which meant to skip mknod operation when run
in user namespace, but instread skipped FIFO and socket files
copy.
Signed-off-by: Maxim Ivanov <ivanov.maxim@gmail.com>
Upstream-commit: 6f084f292932c464a30b56edb9edbe238bdcf0aa
Component: engine
Makes sure that if the user cancels a request that the daemon stops
trying to traverse a directory.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
Upstream-commit: 9d46c4c138d7b3f7778c13fe84857712bd6c97a9
Component: engine
Now all of the storage drivers use the field "storage-driver" in their log
messages, which is set to name of the respective driver.
Storage drivers changed:
- Aufs
- Btrfs
- Devicemapper
- Overlay
- Overlay 2
- Zfs
Signed-off-by: Alejandro GonzÃlez Hevia <alejandrgh11@gmail.com>
Upstream-commit: 9392838150f5495a63f33fed6570ae41f5a6d62e
Component: engine
Move the "unmount and deactivate" code into a separate method, and
optimize it a bit:
1. Do not use filepath.Walk() as there's no requirement to recursively
go into every directory under home/mnt; a list of directories in mnt
is sufficient. With filepath.Walk(), in case some container will fail
to unmount, it'll go through the whole container filesystem which is
excessive and useless.
2. Do not use GetMounts() and check if a directory is mounted; just
unmount it and ignore "not mounted" error. Note the same error
is returned in case of wrong flags set, but as flags are hardcoded
we can safely ignore such case.
While at it, promote "can't unmount" log level from debug to warning.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Upstream-commit: f1a459229724f5e8e440b49f058167c2eeeb2dc6
Component: engine
1. Make sure it's clear the error is from unmount.
2. Simplify the code a bit to make it more readable.
[v2: use errors.Wrap]
[v3: use errors.Wrapf]
[v4: lowercase the error message]
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Upstream-commit: 9d00aedebc25507042c5afd4ab8fc6b333ca7c53
Component: engine
1. Replace EnsureRemoveAll() with Rmdir(), as here we are removing
the container's mount point, which is already properly unmounted
and is therefore an empty directory.
2. Ignore the Rmdir() error (but log it unless it's ENOENT). This
is a mount point, currently unmounted (i.e. an empty directory),
and an older kernel can return EBUSY if e.g. the mount was
leaked to other mount namespaces.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Upstream-commit: 732dd9b848bec70a2ecb5b4998918886a0cec497
Component: engine
It looks like no one uses this function.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Upstream-commit: 0450f61cb995c8fc2f41a6909526be6ed4093565
Component: engine
Before this change, volume management was relying on the fact that
everything the plugin mounts is visible on the host within the plugin's
rootfs. In practice this caused some issues with mount leaks, so we
changed the behavior such that mounts are not visible on the plugin's
rootfs, but available outside of it, which breaks volume management.
To fix the issue, allow the plugin to scope the path correctly rather
than assuming that everything is visible in `p.Rootfs`.
In practice this is just scoping the `PropagatedMount` paths to the
correct host path.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
Upstream-commit: 0e5eaf8ee32662182147f5f62c1bfebef66f5c47
Component: engine
Setting up the mounts on the host increases chances of mount leakage and
makes for more cleanup after the plugin has stopped.
With this change all mounts for the plugin are performed by the
container runtime and automatically cleaned up when the container exits.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
Upstream-commit: a53930a04fa81b082aa78e66b342ff19cc63cc5f
Component: engine
This was added in #36047 just as a way to make sure the tree is fully
unmounted on shutdown.
For ZFS this could be a breaking change since there was no unmount before.
Someone could have setup the zfs tree themselves. It would be better, if
we really do want the cleanup to actually the unpacked layers checking
for mounts rather than a blind recursive unmount of the root.
BTRFS does not use mounts and does not need to unmount anyway.
These was only an unmount to begin with because for some reason the
btrfs tree was being moutned with `private` propagation.
For the other graphdrivers that still have a recursive unmount here...
these were already being unmounted and performing the recursive unmount
shouldn't break anything. If anyone had anything mounted at the
graphdriver location it would have been unmounted on shutdown anyway.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
Upstream-commit: 2fe4f888bee52b1f256d6fa5e20f9b061d30221c
Component: engine
The idea behind making the graphdrivers private is to prevent leaking
mounts into other namespaces.
Unfortunately this is not really what happens.
There is one case where this does work, and that is when the namespace
was created before the daemon's namespace.
However with systemd each system servie winds up with it's own mount
namespace. This causes a race betwen daemon startup and other system
services as to if the mount is actually private.
This also means there is a negative impact when other system services
are started while the daemon is running.
Basically there are too many things that the daemon does not have
control over (nor should it) to be able to protect against these kinds
of leakages. One thing is certain, setting the graphdriver roots to
private disconnects the mount ns heirarchy preventing propagation of
unmounts... new mounts are of course not propagated either, but the
behavior is racey (or just bad in the case of restarting services)... so
it's better to just be able to keep mount propagation in tact.
It also does not protect situations like `-v
/var/lib/docker:/var/lib/docker` where all mounts are recursively bound
into the container anyway.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
Upstream-commit: 9803272f2db84df7955b16c0d847ad72cdc494d1
Component: engine
This is a fix to regression in vfs graph driver introduced by
commit 7a1618ced359a3ac92 ("add quota support to VFS graphdriver").
On some filesystems, vfs fails to init with the following error:
> Error starting daemon: error initializing graphdriver: Failed to mknod
> /go/src/github.com/docker/docker/bundles/test-integration/d6bcf6de610e9/root/vfs/backingFsBlockDev:
> function not implemented
As quota is not essential for vfs, let's ignore (but log as a warning) any error
from quota init.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Upstream-commit: 1e8a087850aa9f96c5000a3ad90757d2e9c0499f
Component: engine
If mknod() returns ENOSYS, it most probably means quota is not supported
here, so return the appropriate error.
This is a conservative* fix to regression in vfs graph driver introduced
by commit 7a1618ced359a3ac92 ("add quota support to VFS graphdriver").
On some filesystems, vfs fails to init with the following error:
> Error starting daemon: error initializing graphdriver: Failed to mknod
> /go/src/github.com/docker/docker/bundles/test-integration/d6bcf6de610e9/root/vfs/backingFsBlockDev:
> function not implemented
Reported-by: Brian Goff <cpuguy83@gmail.com>
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Upstream-commit: 2dd39b7841bdb9968884bbedc5db97ff77d4fe3e
Component: engine
Files that are suffixed with `_linux.go` or `_windows.go` are
already only built on Linux / Windows, so these build-tags
were redundant.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Upstream-commit: 6ed1163c98703f8dd0693cecbadc84d2cda811c3
Component: engine
