Now that most uses of reexec have been replaced with non-reexec
solutions, most of the reexec.Init() calls peppered throughout the test
suites are unnecessary. Furthermore, most of the reexec.Init() calls in
test code neglects to check the return value to determine whether to
exit, which would result in the reexec'ed subprocesses proceeding to run
the tests, which would reexec another subprocess which would proceed to
run the tests, recursively. (That would explain why every reexec
callback used to unconditionally call os.Exit() instead of returning...)
Remove unneeded reexec.Init() calls from test and example code which no
longer needs it, and fix the reexec.Init() calls which are not inert to
exit after a reexec callback is invoked.
Signed-off-by: Cory Snider <csnider@mirantis.com>
(cherry picked from commit 4e0319c878)
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Disables user.Lookup() and net.LookupHost() in the init() function on Windows.
Any package that simply imports pkg/chrootarchive will panic on Windows
Nano Server, due to missing netapi32.dll. While docker itself is not
meant to run on Nano Server, binaries that may import this package and
run on Nano server, will fail even if they don't really use any of the
functionality in this package while running on Nano.
Signed-off-by: Gabriel Adrian Samfira <gsamfira@cloudbasesolutions.com>
This change was introduced early in the development of rootless support,
before all the kinks were worked out and rootlesskit was built. The
author was testing the daemon by inside a user namespace set up by runc,
observed that the unshare(2) syscall was returning EPERM, and assumed
that it was a fundamental limitation of user namespaces. Seeing as the
kernel documentation (of today) disagrees with that assessment and that
unshare demonstrably works inside user namespaces, I can only assume
that the EPERM was due to a quirk of their test environment, such as a
seccomp filter set up by runc blocking the unshare syscall.
https://github.com/moby/moby/pull/20902#issuecomment-236409406
Mount namespaces are necessary to address #38995 and #43390. Revert the
special-casing so those issues can also be fixed for rootless daemons.
This reverts commit dc950567c1.
Signed-off-by: Cory Snider <csnider@mirantis.com>
Unshare the thread's file system attributes and, if applicable, mount
namespace so that the chroot operation does not affect the rest of the
process.
Signed-off-by: Cory Snider <csnider@mirantis.com>
The applyLayer implementation in pkg/chrootarchive has to set the TMPDIR
environment variable so that archive.UnpackLayer() can successfully
create the whiteout-file temp directory. Change UnpackLayer to create
the temporary directory under the destination path so that environment
variables do not need to be touched.
Signed-off-by: Cory Snider <csnider@mirantis.com>
system.MkdirAll is a special version of os.Mkdir to handle creating directories
using Windows volume paths ("\\?\Volume{4c1b02c1-d990-11dc-99ae-806e6f6e6963}").
This may be important when MkdirAll is used, which traverses all parent paths to
create them if missing (ultimately landing on the "volume" path).
Commit 62f648b061 introduced the system.MkdirAll
calls, as a change was made in applyLayer() for Windows to use Windows volume
paths as an alternative for chroot (which is not supported on Windows). Later
iteractions changed this to regular Windows long-paths (`\\?\<path>`) in
230cfc6ed2, and 9b648dfac6.
Such paths are handled by the `os` package.
However, in these tests, the parent path already exists (all paths created are
a direct subdirectory within `tmpDir`). It looks like `MkdirAll` here is used
out of convenience to not have to handle `os.ErrExist` errors. As all these
tests are running in a fresh temporary directory, there should be no need to
handle those, and it's actually desirable to produce an error in that case, as
the directory already existing would be unexpected.
Because of the above, this test changes `system.MkdirAll` to `os.Mkdir`. As we
are changing these lines, this patch also changes the legacy octal notation
(`0700`) to the now preferred `0o700`.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Introduced in 3ac6394b80, which makes no mention
of a reason for extracting to the same directory as we created the archive from,
so I assume this was a copy/paste mistake and the path was meant to be "dest",
not "src".
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
It was only used in a couple of places, and in most places shouldn't be used
as those locations were in unix/linux-only files, so didn't need the wrapper.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
On Linux, when (os/exec.Cmd).SysProcAttr.Pdeathsig is set, the signal
will be sent to the process when the OS thread on which cmd.Start() was
executed dies. The runtime terminates an OS thread when a goroutine
exits after being wired to the thread with runtime.LockOSThread(). If
other goroutines are allowed to be scheduled onto a thread which called
cmd.Start(), an unrelated goroutine could cause the thread to be
terminated and prematurely signal the command. See
https://github.com/golang/go/issues/27505 for more information.
Prevent started subprocesses with Pdeathsig from getting signaled
prematurely by wiring the starting goroutine to the OS thread until the
subprocess has exited. No other goroutines can be scheduled onto a
locked thread so it will remain alive until unlocked or the daemon
process exits.
Signed-off-by: Cory Snider <csnider@mirantis.com>
Older versions of Go don't format comments, so committing this as
a separate commit, so that we can already make these changes before
we upgrade to Go 1.19.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
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>
If chroot is used with a special root directory then create
destination directory within chroot. This works automatically
already due to extractor creating parent paths and is only
used currently with cp where parent paths are actually required
and error will be shown to user before reaching this point.
Signed-off-by: Tonis Tiigi <tonistiigi@gmail.com>
(cherry picked from commit 52d285184068998c22632bfb869f6294b5613a58)
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
(cherry picked from commit 80f1169eca)
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
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>
These tests fail when run by a non-root user
=== RUN TestUntarWithMaliciousSymlinks
archive_unix_test.go:63: assertion failed: expected error to contain "open /safe/host-file: no such file or directory", got "Error processing tar file(exit status 1): Error creating mount namespace before pivot: operation not permitted"
--- FAIL: TestUntarWithMaliciousSymlinks (0.00s)
=== RUN TestTarWithMaliciousSymlinks
archive_unix_test.go:90: /tmp/TestTarWithMaliciousSymlinks400408188
=== RUN TestTarWithMaliciousSymlinks//tmp/TestTarWithMaliciousSymlinks400408188/root/safe_host-file
archive_unix_test.go:155: assertion failed: error is not nil: error processing tar file: Error after fallback to chroot: operation not permitted: exit status 1
=== RUN TestTarWithMaliciousSymlinks//tmp/TestTarWithMaliciousSymlinks400408188/root/safe/_host-file
archive_unix_test.go:155: assertion failed: error is not nil: error processing tar file: Error after fallback to chroot: operation not permitted: exit status 1
=== RUN TestTarWithMaliciousSymlinks//tmp/TestTarWithMaliciousSymlinks400408188/root/safe_
archive_unix_test.go:155: assertion failed: error is not nil: error processing tar file: Error after fallback to chroot: operation not permitted: exit status 1
=== RUN TestTarWithMaliciousSymlinks//tmp/TestTarWithMaliciousSymlinks400408188/root/safe/_
archive_unix_test.go:155: assertion failed: error is not nil: error processing tar file: Error after fallback to chroot: operation not permitted: exit status 1
=== RUN TestTarWithMaliciousSymlinks//tmp/TestTarWithMaliciousSymlinks400408188/root_safe/host-file
archive_unix_test.go:155: assertion failed: error is not nil: error processing tar file: Error after fallback to chroot: operation not permitted: exit status 1
=== RUN TestTarWithMaliciousSymlinks//tmp/TestTarWithMaliciousSymlinks400408188/root_/safe/host-file
archive_unix_test.go:155: assertion failed: error is not nil: error processing tar file: Error after fallback to chroot: operation not permitted: exit status 1
=== RUN TestTarWithMaliciousSymlinks//tmp/TestTarWithMaliciousSymlinks400408188/root_
archive_unix_test.go:155: assertion failed: error is not nil: error processing tar file: Error after fallback to chroot: operation not permitted: exit status 1
--- FAIL: TestTarWithMaliciousSymlinks (0.02s)
--- FAIL: TestTarWithMaliciousSymlinks//tmp/TestTarWithMaliciousSymlinks400408188/root/safe_host-file (0.00s)
--- FAIL: TestTarWithMaliciousSymlinks//tmp/TestTarWithMaliciousSymlinks400408188/root/safe/_host-file (0.00s)
--- FAIL: TestTarWithMaliciousSymlinks//tmp/TestTarWithMaliciousSymlinks400408188/root/safe_ (0.00s)
--- FAIL: TestTarWithMaliciousSymlinks//tmp/TestTarWithMaliciousSymlinks400408188/root/safe/_ (0.00s)
--- FAIL: TestTarWithMaliciousSymlinks//tmp/TestTarWithMaliciousSymlinks400408188/root_safe/host-file (0.00s)
--- FAIL: TestTarWithMaliciousSymlinks//tmp/TestTarWithMaliciousSymlinks400408188/root_/safe/host-file (0.00s)
--- FAIL: TestTarWithMaliciousSymlinks//tmp/TestTarWithMaliciousSymlinks400408188/root_ (0.00s)
FAIL
FAIL github.com/docker/docker/pkg/chrootarchive 0.042s
Signed-off-by: Arnaud Rebillout <elboulangero@gmail.com>
update test to fix go 1.15 linting failure:
pkg/chrootarchive/archive_test.go:103:32: conversion from int to string yields a string of one rune
relates to golang/go 32479
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
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>
Switch to moby/sys/mount and mountinfo. Keep the pkg/mount for potential
outside users.
This commit was generated by the following bash script:
```
set -e -u -o pipefail
for file in $(git grep -l 'docker/docker/pkg/mount"' | grep -v ^pkg/mount); do
sed -i -e 's#/docker/docker/pkg/mount"#/moby/sys/mount"#' \
-e 's#mount\.\(GetMounts\|Mounted\|Info\|[A-Za-z]*Filter\)#mountinfo.\1#g' \
$file
goimports -w $file
done
```
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
also renamed the non-windows variant of this file to be
consistent with other files in this package
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
environment not in the chroot from untrusted files.
See also OpenVZ a3f732ef75/src/enter.c (L227-L234)
Signed-off-by: Justin Cormack <justin.cormack@docker.com>
(cherry picked from commit cea6dca993c2b4cfa99b1e7a19ca134c8ebc236b)
Signed-off-by: Tibor Vass <tibor@docker.com>
Previously only unpack operations were supported with chroot.
This adds chroot support for packing operations.
This prevents potential breakouts when copying data from a container.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
This is useful for preventing CVE-2018-15664 where a malicious container
process can take advantage of a race on symlink resolution/sanitization.
Before this change chrootarchive would chroot to the destination
directory which is attacker controlled. With this patch we always chroot
to the container's root which is not attacker controlled.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
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>
With `rprivate` there exists a race where a reference to a mount has
propagated to the new namespace, when `rprivate` is set the parent
namespace is not able to remove the mount due to that reference.
With `rslave` unmounts will propagate correctly into the namespace and
prevent the sort of transient errors that are possible with `rprivate`.
This is a similar fix to 117c92745b
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
This enables docker cp and ADD/COPY docker build support for LCOW.
Originally, the graphdriver.Get() interface returned a local path
to the container root filesystem. This does not work for LCOW, so
the Get() method now returns an interface that LCOW implements to
support copying to and from the container.
Signed-off-by: Akash Gupta <akagup@microsoft.com>
Changes most references of syscall to golang.org/x/sys/
Ones aren't changes include, Errno, Signal and SysProcAttr
as they haven't been implemented in /x/sys/.
Signed-off-by: Christopher Jones <tophj@linux.vnet.ibm.com>
[s390x] switch utsname from unsigned to signed
per 33267e036f
char in s390x in the /x/sys/unix package is now signed, so
change the buildtags
Signed-off-by: Christopher Jones <tophj@linux.vnet.ibm.com>
There is no case which would resolve in this error. The root user always exists, and if the id maps are empty, the default value of 0 is correct.
Signed-off-by: Daniel Nephin <dnephin@docker.com>
This patch fixed below 4 types of code line
1. Remove unnecessary variable assignment
2. Use variables declaration instead of explicit initial zero value
3. Change variable name to underbar when variable not used
4. Add erro check and return for ignored error
Signed-off-by: Daehyeok Mun <daehyeok@gmail.com>
In some cases, attempting to `docker cp` to a container's volume dir
would fail due to the volume mounts not existing after performing a
bind-mount on the container path prior to doing a pivot_root.
This does not seem to be effecting all systems, but was found to be a
problem on centos.
The solution is to use an `rbind` rather than `bind` so that any
existing mounts are carried over.
The `MakePrivate` on `path` is no longer neccessary since we are already
doing `MakeRPrivate` on `/`.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
