This commit replaces `os.Setenv` with `t.Setenv` in tests. The
environment variable is automatically restored to its original value
when the test and all its subtests complete.
Reference: https://pkg.go.dev/testing#T.Setenv
Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>
Finish the refactor which was partially completed with commit
34536c498d, passing around IdentityMapping structs instead of pairs of
[]IDMap slices.
Existing code which uses []IDMap relies on zero-valued fields to be
valid, empty mappings. So in order to successfully finish the
refactoring without introducing bugs, their replacement therefore also
needs to have a useful zero value which represents an empty mapping.
Change IdentityMapping to be a pass-by-value type so that there are no
nil pointers to worry about.
The functionality provided by the deprecated NewIDMappingsFromMaps
function is required by unit tests to to construct arbitrary
IdentityMapping values. And the daemon will always need to access the
mappings to pass them to the Linux kernel. Accommodate these use cases
by exporting the struct fields instead. BuildKit currently depends on
the UIDs and GIDs methods so we cannot get rid of them yet.
Signed-off-by: Cory Snider <csnider@mirantis.com>
A copy of Go's archive/tar packge was vendored with a patch applied to
mitigate CVE-2019-14271. Vendoring standard library packages is not
supported by Go in module-aware mode, which is getting in the way of
maintenance. A different approach to mitigate the vulnerability is
needed which does not involve vendoring parts of the standard library.
glibc implements name service lookups such as users, groups and DNS
using a scheme known as Name Service Switch. The services are
implemented as modules, shared libraries which glibc dynamically links
into the process the first time a function requiring the module is
called. This is the crux of the vulnerability: if a process linked
against glibc chroots, then calls one of the functions implemented with
NSS for the first time, glibc may load NSS modules out of the chrooted
filesystem.
The API underlying the `docker cp` command is implemented by forking a
new process which chroots into the container's rootfs and writes a tar
stream of files from the container over standard output. It utilizes the
Go standard library's archive/tar package to write the tar stream. It
makes use of the tar.FileInfoHeader function to construct a tar.Header
value from an fs.FileInfo value. In modern versions of Go on *nix
platforms, FileInfoHeader will attempt to resolve the file's UID and GID
to their respective user and group names by calling the os/user
functions LookupId and LookupGroupId. The cgo implementation of os/user
on *nix performs lookups by calling the corresponding libc functions. So
when linked against glibc, calls to tar.FileInfoHeader after the
process has chrooted into the container's rootfs can have the side
effect of loading NSS modules from the container! Without any
mitigations, a malicious container image author can trivially get
arbitrary code execution by leveraging this vulnerability and escape the
chroot (which is not a sandbox) into the host.
Mitigate the vulnerability without patching or forking archive/tar by
hiding the OS-dependent file info from tar.FileInfoHeader which it needs
to perform the lookups. Without that information available it falls back
to populating the tar.Header with only the information obtainable
directly from the FileInfo value without making any calls into os/user.
Fixes#42402
Signed-off-by: Cory Snider <csnider@mirantis.com>
As a matter of fact, there are two frame formats defined by Zstandard: Zstandard frames and Skippable frames.
So we should probably support zstd algorithms with skippable frames.
See https://tools.ietf.org/id/draft-kucherawy-dispatch-zstd-00.html#rfc.section.2 for more details.
Signed-off-by: Da McGrady <dabkb@aol.com>
zstd is a compression algorithm that has a very fast decoder, while
providing also good compression ratios. The fast decoder makes it
suitable for container images, as decompressing the tarballs is a very
expensive operation.
https://github.com/opencontainers/image-spec/pull/788 added support
for zstd to the OCI image specs.
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
The io/ioutil package has been deprecated in Go 1.16. 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>
The implementation in libcontainer/system is quite complicated,
and we only use it to detect if user-namespaces are enabled.
In addition, the implementation in containerd uses a sync.Once,
so that detection (and reading/parsing `/proc/self/uid_map`) is
only performed once.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
There is a race condition in pkg/archive when using `cmd.Start` for pigz
and xz where the `*bufio.Reader` could be returned to the pool while the
command is still writing to it, and then picked up and used by a new
command.
The command is wrapped in a `CommandContext` where the process will be
killed when the context is cancelled, however this is not instantaneous,
so there's a brief window while the command is still running but the
`*bufio.Reader` was already returned to the pool.
wrapReadCloser calls `cancel()`, and then `readBuf.Close()` which
eventually returns the buffer to the pool. However, because cmdStream
runs `cmd.Wait` in a go routine that we never wait for to finish, it is
not safe to return the reader to the pool yet. We need to ensure we
wait for `cmd.Wait` to finish!
Signed-off-by: Stephen Benjamin <stephen@redhat.com>
Signed-off-by: John Howard <jhoward@microsoft.com>
If fixes an error in sameFsTime which was using `==` to compare two times. The correct way is to use go's built-in timea.Equals(timeb).
In changes_windows, it uses sameFsTime to compare mTim of a `system.StatT` to allow TestChangesDirsMutated to operate correctly now.
Note there is slight different between the Linux and Windows implementations of detecting changes. Due to https://github.com/moby/moby/issues/9874,
and the fix at https://github.com/moby/moby/pull/11422, Linux does not consider a change to the directory time as a change. Windows on NTFS
does. See https://github.com/moby/moby/pull/37982 for more information. The result in `TestChangesDirsMutated`, `dir3` is NOT considered a change
in Linux, but IS considered a change on Windows. The test mutates dir3 to have a mtime of +1 second.
With a handful of tests still outstanding, this change ports most of the unit tests under pkg/archive to Windows.
It provides an implementation of `copyDir` in tests for Windows. To make a copy similar to Linux's `cp -a` while preserving timestamps
and links to both valid and invalid targets, xcopy isn't sufficient. So I used robocopy, but had to circumvent certain exit codes that
robocopy exits with which are warnings. Link to article describing this is in the code.
This implements chown support on Windows. Built-in accounts as well
as accounts included in the SAM database of the container are supported.
NOTE: IDPair is now named Identity and IDMappings is now named
IdentityMapping.
The following are valid examples:
ADD --chown=Guest . <some directory>
COPY --chown=Administrator . <some directory>
COPY --chown=Guests . <some directory>
COPY --chown=ContainerUser . <some directory>
On Windows an owner is only granted the permission to read the security
descriptor and read/write the discretionary access control list. This
fix also grants read/write and execute permissions to the owner.
Signed-off-by: Salahuddin Khan <salah@docker.com>
The Golang built-in gzip library is serialized, and fairly slow
at decompressing. It also only decompresses on demand, versus
pipelining decompression.
This change switches to using the pigz external command
for gzip decompression, as opposed to using the built-in
golang one. This code is not vendored, but will be used
if it autodetected as part of the OS.
This also switches to using context, versus a manually
managed channel to manage cancellations, and synchronization.
There is a little bit of weirdness around manually having
to cancel in the error cases.
Signed-off-by: Sargun Dhillon <sargun@sargun.me>
With docker-17.06.0 some images pulled do not extract properly. Some files don't appear in correct directories. This may or may not cause the pull to fail. These images can't be pushed or saved. 17.06 is the first version of Docker built with go1.8.
Cause
There are multiple updates to the tar package in go1.8.
https://go-review.googlesource.com/c/32234/ disables using "prefix" field when new tar archives are being written. Prefix field was previously set when a record in the archive used a path longer than 100 bytes.
Another change https://go-review.googlesource.com/c/31444/ makes the reader ignore the "prefix" field value if the record is in GNU format. GNU format defines that same area should be used for access and modified times. If the "prefix" field is not read, a file will only be extracted by the basename.
The problem is that with a previous version of the golang archive package headers could be written, that use the prefix field while at the same time setting the header format to GNU. This happens when numeric fields are big enough that they can not be written as octal strings and need to be written in binary. Usually, this shouldn't happen: uid, gid, devmajor, devminor can use up to 7 bytes, size and timestamp can use 11. If one of the records does overflow it switches the whole writer to GNU mode and all next files will be saved in GNU format.
Signed-off-by: Tonis Tiigi <tonistiigi@gmail.com>
I noticed that we're using a homegrown package for assertions. The
functions are extremely similar to testify, but with enough slight
differences to be confusing (for example, Equal takes its arguments in a
different order). We already vendor testify, and it's used in a few
places by tests.
I also found some problems with pkg/testutil/assert. For example, the
NotNil function seems to be broken. It checks the argument against
"nil", which only works for an interface. If you pass in a nil map or
slice, the equality check will fail.
In the interest of avoiding NIH, I'm proposing replacing
pkg/testutil/assert with testify. The test code looks almost the same,
but we avoid the confusion of having two similar but slightly different
assertion packages, and having to maintain our own package instead of
using a commonly-used one.
In the process, I found a few places where the tests should halt if an
assertion fails, so I've made those cases (that I noticed) use "require"
instead of "assert", and I've vendored the "require" package from
testify alongside the already-present "assert" package.
Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>
If we are running in a user namespace, don't try to mknod as
it won't be allowed. libcontainer will bind-mount the host's
devices over files in the container anyway, so it's not needed.
The chrootarchive package does a chroot (without mounting /proc) before
its work, so we cannot check /proc/self/uid_map when we need to. So
compute it in advance and pass it along with the tar options.
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Moved a defer up to a better spot.
Fixed TestUntarPathWithInvalidDest to actually fail for the right reason
Closes#18170
Signed-off-by: Doug Davis <dug@us.ibm.com>
The race is between pools.Put which calls buf.Reset and exec.Cmd
doing io.Copy from the buffer; it caused a runtime crash, as
described in #16924:
``` docker-daemon cat the-tarball.xz | xz -d -c -q | docker-untar /path/to/... (aufs ) ```
When docker-untar side fails (like try to set xattr on aufs, or a broken
tar), invokeUnpack will be responsible to exhaust all input, otherwise
`xz` will be write pending for ever.
this change add a receive only channel to cmdStream, and will close it
to notify it's now safe to close the input stream;
in CmdStream the change to use Stdin / Stdout / Stderr keeps the
code simple, os/exec.Cmd will spawn goroutines and call io.Copy automatically.
the CmdStream is actually called in the same file only, change it
lowercase to mark as private.
[...]
INFO[0000] Docker daemon commit=0a8c2e3 execdriver=native-0.2 graphdriver=aufs version=1.8.2
DEBU[0006] Calling POST /build
INFO[0006] POST /v1.20/build?cgroupparent=&cpuperiod=0&cpuquota=0&cpusetcpus=&cpusetmems=&cpushares=0&dockerfile=Dockerfile&memory=0&memswap=0&rm=1&t=gentoo-x32&ulimits=null
DEBU[0008] [BUILDER] Cache miss
DEBU[0009] Couldn't untar /home/lib-docker-v1.8.2-tmp/tmp/docker-build316710953/stage3-x32-20151004.tar.xz to /home/lib-docker-v1.8.2-tmp/aufs/mnt/d909abb87150463939c13e8a349b889a72d9b14f0cfcab42a8711979be285537: Untar re-exec error: exit status 1: output: operation not supported
DEBU[0009] CopyFileWithTar(/home/lib-docker-v1.8.2-tmp/tmp/docker-build316710953/stage3-x32-20151004.tar.xz, /home/lib-docker-v1.8.2-tmp/aufs/mnt/d909abb87150463939c13e8a349b889a72d9b14f0cfcab42a8711979be285537/)
panic: runtime error: slice bounds out of range
goroutine 42 [running]:
bufio.(*Reader).fill(0xc208187800)
/usr/local/go/src/bufio/bufio.go:86 +0x2db
bufio.(*Reader).WriteTo(0xc208187800, 0x7ff39602d150, 0xc2083f11a0, 0x508000, 0x0, 0x0)
/usr/local/go/src/bufio/bufio.go:449 +0x27e
io.Copy(0x7ff39602d150, 0xc2083f11a0, 0x7ff3960261f8, 0xc208187800, 0x0, 0x0, 0x0)
/usr/local/go/src/io/io.go:354 +0xb2
github.com/docker/docker/pkg/archive.func·006()
/go/src/github.com/docker/docker/pkg/archive/archive.go:817 +0x71
created by github.com/docker/docker/pkg/archive.CmdStream
/go/src/github.com/docker/docker/pkg/archive/archive.go:819 +0x1ec
goroutine 1 [chan receive]:
main.(*DaemonCli).CmdDaemon(0xc20809da30, 0xc20800a020, 0xd, 0xd, 0x0, 0x0)
/go/src/github.com/docker/docker/docker/daemon.go:289 +0x1781
reflect.callMethod(0xc208140090, 0xc20828fce0)
/usr/local/go/src/reflect/value.go:605 +0x179
reflect.methodValueCall(0xc20800a020, 0xd, 0xd, 0x1, 0xc208140090, 0x0, 0x0, 0xc208140090, 0x0, 0x45343f, ...)
/usr/local/go/src/reflect/asm_amd64.s:29 +0x36
github.com/docker/docker/cli.(*Cli).Run(0xc208129fb0, 0xc20800a010, 0xe, 0xe, 0x0, 0x0)
/go/src/github.com/docker/docker/cli/cli.go:89 +0x38e
main.main()
/go/src/github.com/docker/docker/docker/docker.go:69 +0x428
goroutine 5 [syscall]:
os/signal.loop()
/usr/local/go/src/os/signal/signal_unix.go:21 +0x1f
created by os/signal.init·1
/usr/local/go/src/os/signal/signal_unix.go:27 +0x35
Signed-off-by: Derek Ch <denc716@gmail.com>
[pkg/archive] Update archive/copy path handling
- Remove unused TarOptions.Name field.
- Add new TarOptions.RebaseNames field.
- Update some of the logic around path dir/base splitting.
- Update some of the logic behind archive entry name rebasing.
[api/types] Add LinkTarget field to PathStat
[daemon] Fix stat, archive, extract of symlinks
These operations *should* resolve symlinks that are in the path but if the
resource itself is a symlink then it *should not* be resolved. This patch
puts this logic into a common function `resolvePath` which resolves symlinks
of the path's dir in scope of the container rootfs but does not resolve the
final element of the path. Now archive, extract, and stat operations will
return symlinks if the path is indeed a symlink.
[api/client] Update cp path hanling
[docs/reference/api] Update description of stat
Add the linkTarget field to the header of the archive endpoint.
Remove path field.
[integration-cli] Fix/Add cp symlink test cases
Copying a symlink should do just that: copy the symlink NOT
copy the target of the symlink. Also, the resulting file from
the copy should have the name of the symlink NOT the name of
the target file.
Copying to a symlink should copy to the symlink target and not
modify the symlink itself.
Docker-DCO-1.1-Signed-off-by: Josh Hawn <josh.hawn@docker.com> (github: jlhawn)
Adds TarResource and CopyTo functions to be used for creating
archives for use with the new `docker cp` behavior.
Adds multiple test cases for the CopyFrom and CopyTo
functions in the pkg/archive package.
Docker-DCO-1.1-Signed-off-by: Josh Hawn <josh.hawn@docker.com> (github: jlhawn)
