Prepares the CRI image service for splitting CRI into multiple plugins.
Also prepares for config migration which will spread across multiple
different plugins.
Signed-off-by: Derek McGowan <derek@mcg.dev>
It's to ensure the data integrity during unexpected power failure.
Background:
Since release 1.3, in Linux system, containerD unpacks and writes files into
overlayfs snapshot directly. It doesn’t involve any mount-umount operations
so that the performance of pulling image has been improved.
As we know, the umount syscall for overlayfs will force kernel to flush
all the dirty pages into disk. Without umount syscall, the files’ data relies
on kernel’s writeback threads or filesystem's commit setting (for
instance, ext4 filesystem).
The files in committed snapshot can be loss after unexpected power failure.
However, the snapshot has been committed and the metadata also has been
fsynced. There is data inconsistency between snapshot metadata and files
in that snapshot.
We, containerd, received several issues about data loss after unexpected
power failure.
* https://github.com/containerd/containerd/issues/5854
* https://github.com/containerd/containerd/issues/3369#issuecomment-1787334907
Solution:
* Option 1: SyncFs after unpack
Linux platform provides [syncfs][syncfs] syscall to synchronize just the
filesystem containing a given file.
* Option 2: Fsync directories recursively and fsync on regular file
The fsync doesn't support symlink/block device/char device files. We
need to use fsync the parent directory to ensure that entry is
persisted.
However, based on [xfstest-dev][xfstest-dev], there is no case to ensure
fsync-on-parent can persist the special file's metadata, for example,
uid/gid, access mode.
Checkout [generic/690][generic/690]: Syncing parent dir can persist
symlink. But for f2fs, it needs special mount option. And it doesn't say
that uid/gid can be persisted. All the details are behind the
implemetation.
> NOTE: All the related test cases has `_flakey_drop_and_remount` in
[xfstest-dev].
Based on discussion about [Documenting the crash-recovery guarantees of Linux file systems][kernel-crash-recovery-data-integrity],
we can't rely on Fsync-on-parent.
* Option 1 is winner
This patch is using option 1.
There is test result based on [test-tool][test-tool].
All the networking traffic created by pull is local.
* Image: docker.io/library/golang:1.19.4 (992 MiB)
* Current: 5.446738579s
* WIOS=21081, WBytes=1329741824, RIOS=79, RBytes=1197056
* Option 1: 6.239686088s
* WIOS=34804, WBytes=1454845952, RIOS=79, RBytes=1197056
* Option 2: 1m30.510934813s
* WIOS=42143, WBytes=1471397888, RIOS=82, RBytes=1209344
* Image: docker.io/tensorflow/tensorflow:latest (1.78 GiB, ~32590 Inodes)
* Current: 8.852718042s
* WIOS=39417, WBytes=2412818432, RIOS=2673, RBytes=335987712
* Option 1: 9.683387174s
* WIOS=42767, WBytes=2431750144, RIOS=89, RBytes=1238016
* Option 2: 1m54.302103719s
* WIOS=54403, WBytes=2460528640, RIOS=1709, RBytes=208237568
The Option 1 will increase `wios`. So, the `image_pull_with_sync_fs` is
option in CRI plugin.
[syncfs]: <https://man7.org/linux/man-pages/man2/syncfs.2.html>
[xfstest-dev]: <https://git.kernel.org/pub/scm/fs/xfs/xfstests-dev.git>
[generic/690]: <https://git.kernel.org/pub/scm/fs/xfs/xfstests-dev.git/tree/tests/generic/690?h=v2023.11.19>
[kernel-crash-recovery-data-integrity]: <https://lore.kernel.org/linux-fsdevel/1552418820-18102-1-git-send-email-jaya@cs.utexas.edu/>
[test-tool]: <a17fb2010d/contrib/syncfs/containerd/main_test.go (L51)>
Signed-off-by: Wei Fu <fuweid89@gmail.com>
go1.21.5 (released 2023-12-05) includes security fixes to the go command,
and the net/http and path/filepath packages, as well as bug fixes to the
compiler, the go command, the runtime, and the crypto/rand, net, os, and
syscall packages. See the Go 1.21.5 milestone on our issue tracker for
details:
- https://github.com/golang/go/issues?q=milestone%3AGo1.21.5+label%3ACherryPickApproved
- full diff: https://github.com/golang/go/compare/go1.21.4...go1.21.5
from the security mailing:
[security] Go 1.21.5 and Go 1.20.12 are released
Hello gophers,
We have just released Go versions 1.21.5 and 1.20.12, minor point releases.
These minor releases include 3 security fixes following the security policy:
- net/http: limit chunked data overhead
A malicious HTTP sender can use chunk extensions to cause a receiver
reading from a request or response body to read many more bytes from
the network than are in the body.
A malicious HTTP client can further exploit this to cause a server to
automatically read a large amount of data (up to about 1GiB) when a
handler fails to read the entire body of a request.
Chunk extensions are a little-used HTTP feature which permit including
additional metadata in a request or response body sent using the chunked
encoding. The net/http chunked encoding reader discards this metadata.
A sender can exploit this by inserting a large metadata segment with
each byte transferred. The chunk reader now produces an error if the
ratio of real body to encoded bytes grows too small.
Thanks to Bartek Nowotarski for reporting this issue.
This is CVE-2023-39326 and Go issue https://go.dev/issue/64433.
- cmd/go: go get may unexpectedly fallback to insecure git
Using go get to fetch a module with the ".git" suffix may unexpectedly
fallback to the insecure "git://" protocol if the module is unavailable
via the secure "https://" and "git+ssh://" protocols, even if GOINSECURE
is not set for said module. This only affects users who are not using
the module proxy and are fetching modules directly (i.e. GOPROXY=off).
Thanks to David Leadbeater for reporting this issue.
This is CVE-2023-45285 and Go issue https://go.dev/issue/63845.
- path/filepath: retain trailing \ when cleaning paths like \\?\c:\
Go 1.20.11 and Go 1.21.4 inadvertently changed the definition of the
volume name in Windows paths starting with \\?\, resulting in
filepath.Clean(\\?\c:\) returning \\?\c: rather than \\?\c:\ (among
other effects). The previous behavior has been restored.
This is an update to CVE-2023-45283 and Go issue https://go.dev/issue/64028.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
go1.21.4 (released 2023-11-07) includes security fixes to the path/filepath
package, as well as bug fixes to the linker, the runtime, the compiler, and
the go/types, net/http, and runtime/cgo packages. See the Go 1.21.4 milestone
on our issue tracker for details:
- https://github.com/golang/go/issues?q=milestone%3AGo1.21.4+label%3ACherryPickApproved
- full diff: https://github.com/golang/go/compare/go1.21.3...go1.21.4
from the security mailing:
[security] Go 1.21.4 and Go 1.20.11 are released
Hello gophers,
We have just released Go versions 1.21.4 and 1.20.11, minor point releases.
These minor releases include 2 security fixes following the security policy:
- path/filepath: recognize `\??\` as a Root Local Device path prefix.
On Windows, a path beginning with `\??\` is a Root Local Device path equivalent
to a path beginning with `\\?\`. Paths with a `\??\` prefix may be used to
access arbitrary locations on the system. For example, the path `\??\c:\x`
is equivalent to the more common path c:\x.
The filepath package did not recognize paths with a `\??\` prefix as special.
Clean could convert a rooted path such as `\a\..\??\b` into
the root local device path `\??\b`. It will now convert this
path into `.\??\b`.
`IsAbs` did not report paths beginning with `\??\` as absolute.
It now does so.
VolumeName now reports the `\??\` prefix as a volume name.
`Join(`\`, `??`, `b`)` could convert a seemingly innocent
sequence of path elements into the root local device path
`\??\b`. It will now convert this to `\.\??\b`.
This is CVE-2023-45283 and https://go.dev/issue/63713.
- path/filepath: recognize device names with trailing spaces and superscripts
The `IsLocal` function did not correctly detect reserved names in some cases:
- reserved names followed by spaces, such as "COM1 ".
- "COM" or "LPT" followed by a superscript 1, 2, or 3.
`IsLocal` now correctly reports these names as non-local.
This is CVE-2023-45284 and https://go.dev/issue/63713.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
This is effectively a revert of 2ac9968401, which
switched from os/exec to the golang.org/x/sys/execabs package to mitigate
security issues (mainly on Windows) with lookups resolving to binaries in the
current directory.
from the go1.19 release notes https://go.dev/doc/go1.19#os-exec-path
> ## PATH lookups
>
> Command and LookPath no longer allow results from a PATH search to be found
> relative to the current directory. This removes a common source of security
> problems but may also break existing programs that depend on using, say,
> exec.Command("prog") to run a binary named prog (or, on Windows, prog.exe) in
> the current directory. See the os/exec package documentation for information
> about how best to update such programs.
>
> On Windows, Command and LookPath now respect the NoDefaultCurrentDirectoryInExePath
> environment variable, making it possible to disable the default implicit search
> of “.” in PATH lookups on Windows systems.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
