configs package can no longer be built on non-Linux OS, such as Darwin.
When running `GOOS=darwin go build` on the packge, we had the following
errors:
```
./configs/mount.go:34:16: undefined: unix.MountAttr
./configs/mount.go:47:22: undefined: unix.MS_BIND
```
Let's ensure that the linux specific bits are handled in mount_linux.go,
and introduce a _unsupported file, similar to how cgroups file is
handled within the package. This'll facilitate utilization of the pkg
for other projects that care about Darwin.
Signed-off-by: Eric Ernst <eric_ernst@apple.com>
This is aimed at solving the problem of cgroup v2 memory controller
behavior which is not compatible with that of cgroup v1.
In cgroup v1, if the new memory limit being set is lower than the
current usage, setting the new limit fails.
In cgroup v2, same operation succeeds, and the container is OOM killed.
Introduce a new setting, memory.checkBeforeUpdate, and use it to mimic
cgroup v1 behavior.
Note that this is not 100% reliable because of TOCTOU, but this is the
best we can do.
Add some test cases.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Since Go 1.19, godoc recognizes lists, code blocks, headings etc. It
also reformats the sources making it more apparent that these features
are used.
Fix a few places where it misinterpreted the formatting (such as
indented vs unindented), and format the result using the gofumpt
from HEAD, which already incorporates gofmt 1.19 changes.
Some more fixes (and enhancements) might be required.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
the struct blockIODevice is used in an exported struct but it is not itself exported rendering that type inaccessible to
outside projects
Signed-off-by: cdoern <cdoern@redhat.com>
1. Fix function docs. In particular, remove the part
which is not true ("verifies that the user isn't trying to set up any
mounts they don't have the rights to do"), and fix the part that
says "that doesn't resolve to root" (which is no longer true since
commit d8b669400a).
2. Replace fmt.Sscanf (which is slow and does lots of allocations)
with strings.TrimPrefix and strconv.Atoi.
3. Add a benchmark for rootlessEUIDMount. Comparing the old and the new
implementations:
name old time/op new time/op delta
RootlessEUIDMount-4 1.01µs ± 2% 0.16µs ± 1% -84.15% (p=0.008 n=5+5)
name old alloc/op new alloc/op delta
RootlessEUIDMount-4 224B ± 0% 80B ± 0% -64.29% (p=0.008 n=5+5)
name old allocs/op new allocs/op delta
RootlessEUIDMount-4 7.00 ± 0% 1.00 ± 0% -85.71% (p=0.008 n=5+5)
Note this code is already tested (in rootless_test.go).
Fixes: d8b669400a
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Don't require CAT or MBA because we don't detect those correctly (we
don't support L2 or L3DATA/L3CODE for example, and in the future
possibly even more). With plain "ClosId mode" we don't really care: we
assign the container to a pre-configured CLOS without trying to do
anything smarter.
Moreover, this was a duplicate/redundant check anyway, as for CAT and
MBA there is another specific sanity check that is done if L3 or MB
is specified in the config.
Signed-off-by: Markus Lehtonen <markus.lehtonen@intel.com>
We only have one implementation of config validator, which is always
used. It makes no sense to have Validator interface.
Having validate.Validator field in Factory does not make sense for all
the same reasons.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Those were added by commit 59c5c3ac0 back in Apr 2015, but AFAICS were
never used and are obsoleted by more generic container hooks (initially
added by commit 05567f2c94 in Sep 2015).
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
The new mount option "rro" makes the mount point recursively read-only,
by calling `mount_setattr(2)` with `MOUNT_ATTR_RDONLY` and `AT_RECURSIVE`.
https://man7.org/linux/man-pages/man2/mount_setattr.2.html
Requires kernel >= 5.12.
The "rro" option string conforms to the proposal in util-linux/util-linux Issue 1501.
Fix issue 2823
Similary, this commit also adds the following mount options:
- rrw
- r[no]{suid,dev,exec,relatime,atime,strictatime,diratime,symfollow}
Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>
Delegating cgroups to the container enables more complex workloads,
including systemd-based workloads. The OCI runtime-spec was
recently updated to explicitly admit such delegation, through
specification of cgroup ownership semantics:
https://github.com/opencontainers/runtime-spec/pull/1123
Pursuant to the updated OCI runtime-spec, change the ownership of
the container's cgroup directory and particular files therein, when
using cgroups v2 and when the cgroupfs is to be mounted read/write.
As a result of this change, systemd workloads can run in isolated
user namespaces on OpenShift when the sandbox's cgroupfs is mounted
read/write.
It might be possible to implement this feature in other cgroup
managers, but that work is deferred.
Signed-off-by: Fraser Tweedale <ftweedal@redhat.com>
Runtime spec says:
> sysctl (object, OPTIONAL) allows kernel parameters to be modified at
> runtime for the container. For more information, see the sysctl(8)
> man page.
and sysctl(8) says:
> variable
> The name of a key to read from. An example is
> kernel.ostype. The '/' separator is also accepted in place of a '.'.
Apparently, runc config validator do not support sysctls with / as a
separator. Fortunately this is a one-line fix.
Add some more test data where / is used as a separator.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
The source of the bind mount might not be accessible in a different user
namespace because a component of the source path might not be traversed
under the users and groups mapped inside the user namespace. This caused
errors such as the following:
# time="2020-06-22T13:48:26Z" level=error msg="container_linux.go:367:
starting container process caused: process_linux.go:459:
container init caused: rootfs_linux.go:58:
mounting \"/tmp/busyboxtest/source-inaccessible/dir\"
to rootfs at \"/tmp/inaccessible\" caused:
stat /tmp/busyboxtest/source-inaccessible/dir: permission denied"
To solve this problem, this patch performs the following:
1. in nsexec.c, it opens the source path in the host userns (so we have
the right permissions to open it) but in the container mntns (so the
kernel cross mntns mount check let us mount it later:
https://github.com/torvalds/linux/blob/v5.8/fs/namespace.c#L2312).
2. in nsexec.c, it passes the file descriptors of the source to the
child process with SCM_RIGHTS.
3. In runc-init in Golang, it finishes the mounts while inside the
userns even without access to the some components of the source
paths.
Passing the fds with SCM_RIGHTS is necessary because once the child
process is in the container mntns, it is already in the container userns
so it cannot temporarily join the host mntns.
This patch uses the existing mechanism with _LIBCONTAINER_* environment
variables to pass the file descriptors from runc to runc init.
This patch uses the existing mechanism with the Netlink-style bootstrap
to pass information about the list of source mounts to nsexec.c.
Rootless containers don't use this bind mount sources fdpassing
mechanism because we can't setns() to the target mntns in a rootless
container (we don't have the privileges when we are in the host userns).
This patch takes care of using O_CLOEXEC on mount fds, and close them
early.
Fixes: #2484.
Signed-off-by: Alban Crequy <alban@kinvolk.io>
Signed-off-by: Rodrigo Campos <rodrigo@kinvolk.io>
Co-authored-by: Rodrigo Campos <rodrigo@kinvolk.io>
1. Make Rootless and Systemd flags part of config.Cgroups.
2. Make all cgroup managers (not just fs2) return error (so it can do
more initialization -- added by the following commits).
3. Replace complicated cgroup manager instantiation in factory_linux
by a single (and simple) libcontainer/cgroups/manager.New() function.
4. getUnifiedPath is simplified to check that only a single path is
supplied (rather than checking that other paths, if supplied,
are the same).
[v2: can't -> cannot]
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Two new seccomp actions have been added to the libseccomp-golang
dependency, which can be now supported by runc, too.
ActKillThread kills the thread that violated the rule. It is the same as
ActKill. All other threads from the same thread group will continue to
execute.
ActKillProcess kills the process that violated the rule. All threads in
the thread group are also terminated. This action is only usable when
libseccomp API level 3 or higher is supported.
Signed-off-by: Sascha Grunert <sgrunert@redhat.com>
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
This commit implements support for the SCMP_ACT_NOTIFY action. It
requires libseccomp-2.5.0 to work but runc still works with older
libseccomp if the seccomp policy does not use the SCMP_ACT_NOTIFY
action.
A new synchronization step between runc[INIT] and runc run is introduced
to pass the seccomp fd. runc run fetches the seccomp fd with pidfd_get
from the runc[INIT] process and sends it to the seccomp agent using
SCM_RIGHTS.
As suggested by @kolyshkin, we also make writeSync() a wrapper of
writeSyncWithFd() and wrap the error there. To avoid pointless errors,
we made some existing code paths just return the error instead of
re-wrapping it. If we don't do it, error will look like:
writing syncT <act>: writing syncT: <err>
By adjusting the code path, now they just look like this
writing syncT <act>: <err>
Signed-off-by: Alban Crequy <alban@kinvolk.io>
Signed-off-by: Rodrigo Campos <rodrigo@kinvolk.io>
Co-authored-by: Rodrigo Campos <rodrigo@kinvolk.io>
Go 1.17 introduce this new (and better) way to specify build tags.
For more info, see https://golang.org/design/draft-gobuild.
As a way to seamlessly switch from old to new build tags, gofmt (and
gopls) from go 1.17 adds the new tags along with the old ones.
Later, when go < 1.17 is no longer supported, the old build tags
can be removed.
Now, as I started to use latest gopls (v0.7.1), it adds these tags
while I edit. Rather than to randomly add new build tags, I guess
it is better to do it once for all files.
Mind that previous commits removed some tags that were useless,
so this one only touches packages that can at least be built
on non-linux.
Brought to you by
go1.17 fmt ./...
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
All the errors returned from Validate should tell about a configuration
error. Some were lacking a context, so add it.
While at it, fix abusing fmt.Errorf and logrus.Warnf where the argument
do not contain %-style formatting.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
This is helpful to kubernetes in cases it knows for sure that the freeze
is not required (since it created the systemd unit with no device
restrictions).
As the code is trivial, no tests are required.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Handle ClosID parameter of IntelRdt. Makes it possible to use
pre-configured classes/ClosIDs and avoid running out of available IDs
which easily happens with per-container classes.
Remove validator checks for empty L3CacheSchema and MemBwSchema fields
in order to be able to leave them empty, and only specify ClosID for
a pre-configured class.
Signed-off-by: Markus Lehtonen <markus.lehtonen@intel.com>
This was initially added by commits 41d9d26513 and 4a8f0b4db4,
apparently to implement docker run --cgroup container:ID, which was
never merged. Therefore, this code is not and was never used.
It needs to be removed mainly because having it makes it much harder to
understand how cgroup manager works (because with this in place we have
not one or two but three sets of cgroup paths to think about).
Note if the paths are known and there is a need to add a PID to existing
cgroup, cgroup manager is not needed at all -- something like
cgroups.WriteCgroupProc or cgroups.EnterPid is sufficient (and the
latter is what runc exec uses in (*setnsProcess).start).
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Replace ioutil.TempDir (mostly) with t.TempDir, which require no
explicit cleanup.
While at it, fix incorrect usage of os.ModePerm in libcontainer/intelrdt
test. This is supposed to be a mask, not mode bits.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
This should result in no change when the error is printed, but make the
errors returned unwrappable, meaning errors.As and errors.Is will work.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Using fmt.Errorf for errors that do not have %-style formatting
directives is an overkill. Switch to errors.New.
Found by
git grep fmt.Errorf | grep -v ^vendor | grep -v '%'
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Commits 1f1e91b1a0 and 2192670a24
added validation for mountpoints to be an absolute path, to match the OCI
specs.
Unfortunately, the old behavior (accepting the path to be a relative path)
has been around for a long time, and although "not according to the spec",
various higher level runtimes rely on this behavior.
While higher level runtime have been updated to address this requirement,
there will be a transition period before all runtimes are updated to carry
these fixes.
This patch relaxes the validation, to generate a WARNING instead of failing,
allowing runtimes to update (but allowing them to update runc to the current
version, which includes security fixes).
We can remove this exception in a future patch release.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
These were deprecated and moved; the stubs were included in the
last two (rc94, rc95) releases, so external consumers would have
the chance to update their code.
Removing this so that this doesn't get into v1.0.0 GA
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
The runc update CLI is not able to modify devices, so let's set SkipDevices
(so that a cgroup controller won't try to update devices cgroup).
This helps use cases when some other device management (NVIDIA GPUs)
applies its configuration on top of what runc does.
Make sure we do not save SkipDevices into state.json.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
gofumpt (mvdan.cc/gofumpt) is a fork of gofmt with stricter rules.
Brought to you by
git ls-files \*.go | grep -v ^vendor/ | xargs gofumpt -s -w
Looking at the diff, all these changes make sense.
Also, replace gofmt with gofumpt in golangci.yml.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
wineway