The io/ioutil package has been deprecated as of Go 1.16, see
https://golang.org/doc/go1.16#ioutil. This commit replaces the existing
io/ioutil functions with their new definitions in io and os packages.
Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>
Go 1.15.7 contained a security fix for CVE-2021-3115, which allowed arbitrary
code to be executed at build time when using cgo on Windows. This issue also
affects Unix users who have “.” listed explicitly in their PATH and are running
“go get” outside of a module or with module mode disabled.
This issue is not limited to the go command itself, and can also affect binaries
that use `os.Command`, `os.LookPath`, etc.
From the related blogpost (ttps://blog.golang.org/path-security):
> Are your own programs affected?
>
> If you use exec.LookPath or exec.Command in your own programs, you only need to
> be concerned if you (or your users) run your program in a directory with untrusted
> contents. If so, then a subprocess could be started using an executable from dot
> instead of from a system directory. (Again, using an executable from dot happens
> always on Windows and only with uncommon PATH settings on Unix.)
>
> If you are concerned, then we’ve published the more restricted variant of os/exec
> as golang.org/x/sys/execabs. You can use it in your program by simply replacing
This patch replaces all uses of `os/exec` with `golang.org/x/sys/execabs`. While
some uses of `os/exec` should not be problematic (e.g. part of tests), it is
probably good to be consistent, in case code gets moved around.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
dmsetup does not discard blocks when removing a thin device. The unused blocks
are reused by the thin-pool, but will remain allocated in the underlying
device indefinitely. For loop device backed thin-pools, this results in
"lost" disk space in the underlying file system as the blocks remain allocated
in the loop device's backing file.
This change adds an option, discard_blocks, to the devmapper snapshotter which
causes the snapshotter to issue blkdiscard ioctls on the thin device before
removal. With this option enabled, loop device setups will see disk space
return to the underlying filesystem immediately on exiting a container.
Fixes#5691
Signed-off-by: Kern Walster <walster@amazon.com>
No need to use the private losetup command line wrapper package.
The generic package provides the same functionality.
Signed-off-by: Peng Tao <bergwolf@hyper.sh>
The rollback mechanism is implemented by calling deleteDevice() and
RemoveDevice(). But RemoveDevice() is internally calling
deleteDevice() as well.
Since a device will be deleted by first deleteDevice(),
RemoveDevice() always will see ENODATA. The specific error must be
ignored to remove the device's metadata correctly.
Signed-off-by: Kazuyoshi Kato <katokazu@amazon.com>
- reproducer
1. stop a container;
2. reboot, or dmsetup remove its corresponding dm device;
3. start the container, it will fail like:
"""
Error: failed to start containers: {"message":"failed to create container(4f33d2760760c41518a84821153ccdf7f80980b797b783cdd75178fc6ca0bf4b) on containerd: failed to create task for container(4f33d2760760c41518a84821153ccdf7f80980b797b783cdd75178fc6ca0bf4b): failed to mount rootfs component &{ext4 /dev/mapper/vg0-mythinpool-snap-2 []}: no such file or directory: unknown"}
"""
- how the fix works
activate the dm device if necessary, and give a warn msg:
"""
time="2019-08-21T22:44:08.422695797+08:00" level=warning msg="devmapper device \"vg0-mythinpool-snap-2\" marked as \"Activated\" but not active, activating it"
"""
Signed-off-by: Eric Ren <renzhen@linux.alibaba.com>
1. reason to deactivate committed snapshot
The thin device will not be used for IO after committed,
and further thin snapshotting is OK using an inactive thin
device as origin. The benefits to deactivate are:
- device is not unneccesary visible avoiding any unexpected IO;
- save useless kernel data structs for maintaining active dm.
Quote from kernel doc (Documentation/device-mapper/provisioning.txt):
"
ii) Using an internal snapshot.
Once created, the user doesn't have to worry about any connection
between the origin and the snapshot. Indeed the snapshot is no
different from any other thinly-provisioned device and can be
snapshotted itself via the same method. It's perfectly legal to
have only one of them active, and there's no ordering requirement on
activating or removing them both. (This differs from conventional
device-mapper snapshots.)
"
2. an thinpool metadata bug is naturally removed
An problem happens when failed to suspend/resume origin thin device
when creating snapshot:
"failed to create snapshot device from parent vg0-mythinpool-snap-3"
error="failed to save initial metadata for snapshot "vg0-mythinpool-snap-19":
object already exists"
This issue occurs because when failed to create snapshot, the
snapshotter.store can be rollbacked, but the thin pool metadata
boltdb failed to rollback in PoolDevice.CreateSnapshotDevice(),
therefore metadata becomes inconsistent: the snapshotID is not
taken in snapshotter.store, but saved in pool metadata boltdb.
The cause is, in PoolDevice.CreateSnapshotDevice(), the defer calls
are invoked on "first-in-last-out" order. When the error happens
on the "resume device" defer call, the metadata is saved and
snapshot is created, which has no chance to be rollbacked.
Signed-off-by: Eric Ren <renzhen@linux.alibaba.com>
