When C/R was implemented, it was enough to call manager.Set to apply
limits and to move a task. Now .Set() and .Apply() have to be called
separately.
Fixes: 8a740d5391 ("libcontainer: cgroups: don't Set in Apply")
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>
Instead of relying on version numbers it is possible to check if CRIU
actually supports certain features. This introduces an initial
implementation to check if CRIU and the underlying kernel actually
support dirty memory tracking for memory pre-dumping.
Upstream CRIU also supports the lazy-page migration feature check and
additional feature checks can be included in CRIU to reduce the version
number parsing. There are also certain CRIU features which depend on one
side on the CRIU version but also require certain kernel versions to
actually work. CRIU knows if it can do certain things on the kernel it
is running on and using the feature check RPC interface makes it easier
for runc to decide if the criu+kernel combination will support that
feature.
Feature checking was introduced with CRIU 1.8. Running with older CRIU
versions will ignore the feature check functionality and behave just
like it used to.
v2:
- Do not use reflection to compare requested and responded
features. Checking which feature is available is now hardcoded
and needs to be adapted for every new feature check. The code
is now much more readable and simpler.
v3:
- Move the variable criuFeat out of the linuxContainer struct,
as it is not container specific. Now it is a global variable.
Signed-off-by: Adrian Reber <areber@redhat.com>
The original implementation is in C, which increases cognitive load and
possibly might cause us problems in the future. Since sys/unix is better
maintained than the syscall standard library switching makes more sense.
Signed-off-by: Aleksa Sarai <asarai@suse.de>
Since this is a runC-specific feature, this belongs here over in
opencontainers/ocitools (which is for generic OCI runtimes).
In addition, we don't create a new network namespace. This is because
currently if you want to set up a veth bridge you need CAP_NET_ADMIN in
both network namespaces' pinned user namespace to create the necessary
interfaces in each network namespace.
Signed-off-by: Aleksa Sarai <asarai@suse.de>
If the stdio of the container is owned by a group which is not mapped in
the user namespace, attempting to fchown the file descriptor will result
in EINVAL. Counteract this by simply not doing an fchown if the group
owner of the file descriptor has no host mapping according to the
configured GIDMappings.
Signed-off-by: Aleksa Sarai <asarai@suse.de>
Previously Host{U,G}ID only gave you the root mapping, which isn't very
useful if you are trying to do other things with the IDMaps.
Signed-off-by: Aleksa Sarai <asarai@suse.de>
The rootless cgroup manager acts as a noop for all set and apply
operations. It is just used for rootless setups. Currently this is far
too simple (we need to add opportunistic cgroup management), but is good
enough as a first-pass at a noop cgroup manager.
Signed-off-by: Aleksa Sarai <asarai@suse.de>
This enables the support for the rootless container mode. There are many
restrictions on what rootless containers can do, so many different runC
commands have been disabled:
* runc checkpoint
* runc events
* runc pause
* runc ps
* runc restore
* runc resume
* runc update
The following commands work:
* runc create
* runc delete
* runc exec
* runc kill
* runc list
* runc run
* runc spec
* runc state
In addition, any specification options that imply joining cgroups have
also been disabled. This is due to support for unprivileged subtree
management not being available from Linux upstream.
Signed-off-by: Aleksa Sarai <asarai@suse.de>
Effectively, !dumpable makes implementing rootless containers quite
hard, due to a bunch of different operations on /proc/self no longer
being possible without reordering everything.
!dumpable only really makes sense when you are switching between
different security contexts, which is only the case when we are joining
namespaces. Unfortunately this means that !dumpable will still have
issues in this instance, and it should only be necessary to set
!dumpable if we are not joining USER namespaces (new kernels have
protections that make !dumpable no longer necessary). But that's a topic
for another time.
This also includes code to unset and then re-set dumpable when doing the
USER namespace mappings. This should also be safe because in principle
processes in a container can't see us until after we fork into the PID
namespace (which happens after the user mapping).
In rootless containers, it is not possible to set a non-dumpable
process's /proc/self/oom_score_adj (it's owned by root and thus not
writeable). Thus, it needs to be set inside nsexec before we set
ourselves as non-dumpable.
Signed-off-by: Aleksa Sarai <asarai@suse.de>
When process config doesnt specify capabilities anywhere, we should not panic
because setting capabilities are optional.
Signed-off-by: Daniel Dao <dqminh89@gmail.com>
This reverts commit d4091ef151.
d4091ef151 ("fix minor issue") doesn't actually make any sense, and
actually makes the code more confusing.
Signed-off-by: Aleksa Sarai <asarai@suse.de>
This maybe a nice extra but it adds complication to the usecase. The
contract is listen on the socket and you get an fd to the pty master and
that is that.
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
In container process's Init function, we use
fd + execFifoFilename to open exec fifo, so this
field in init config is never used.
Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>
Fixes: #1347Fixes: #1083
The root cause of #1083 is because we're joining an
existed cgroup whose kmem accouting is not initialized,
and it has child cgroup or tasks in it.
Fix it by checking if the cgroup is first time created,
and we should enable kmem accouting if the cgroup is
craeted by libcontainer with or without kmem limit
configed. Otherwise we'll get issue like #1347
Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>
It should not be binded to container creation, for
example, runc restore needs to create a
libcontainer.Container, but it won't need exec fifo.
So create exec fifo when container is started or run,
where we really need it.
Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>
The error message added here provides no value as the caller already
knows all the added details. However it is covering up the underyling
system error (typically `ENOTSUP`). There is no way to handle this error before
this change.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
getDevices() has been updated to skip `/dev/.lxc` and `/dev/.lxd-mounts`, which was breaking privileged Docker containers running on runC, inside of LXD managed Linux Containers
Signed-off-by: Carlton-Semple <carlton.semple@ibm.com>
CRIU gets pre-dump to complete iterative migration.
pre-dump saves process memory info only. And it need parent-path
to specify the former memory files.
This patch add pre-dump and parent-path arguments to runc checkpoint
Signed-off-by: Deng Guangxing <dengguangxing@huawei.com>
Signed-off-by: Adrian Reber <areber@redhat.com>
As the runtime-spec allows it, we want to be able to specify overlayfs
mounts with:
{
"destination": "/etc/pki",
"type": "overlay",
"source": "overlay",
"options": [
"lowerdir=/etc/pki:/home/amurdaca/go/src/github.com/opencontainers/runc/rootfs_fedora/etc/pki"
]
},
This patch takes care of allowing overlayfs mounts. Both RO and RW
should be supported.
Signed-off-by: Antonio Murdaca <runcom@redhat.com>