Nomad can only use cgroups to control resource requirements if all the cgroups
controllers are actually enabled. Add this to our requirements documentation as
well as the impacted `exec` and `java` task drivers.
Linux capabilities configurable by the task must be a subset of those configured
in the plugin configuration. Clarify this implies that `"all"` is not permitted
if the plugin is not also configured to allow all capabilities.
Fixes: https://github.com/hashicorp/nomad/issues/19059
The exec driver and other drivers derived from the shared executor check the
path of the command before handing off to libcontainer to ensure that the
command doesn't escape the sandbox. But we don't check any host volume mounts,
which should be safe to use as a source for executables if we're letting the
user mount them to the container in the first place.
Check the mount config to verify the executable lives in the mount's host path,
but then return an absolute path within the mount's task path so that we can hand
that off to libcontainer to run.
Includes a good bit of refactoring here because the anchoring of the final task
path has different code paths for inside the task dir vs inside a mount. But
I've fleshed out the test coverage of this a good bit to ensure we haven't
created any regressions in the process.
Update docs for allow_caps, cap_add, cap_drop in exec/java/docker driver
pages. Also update upgrade guide with guidance on new default linux
capabilities for exec and java drivers.
This PR adds pid_mode and ipc_mode options to the exec and java task
driver config options. By default these will defer to the default_pid_mode
and default_ipc_mode agent plugin options created in #9969. Setting
these values to "host" mode disables isolation for the task. Doing so
is not recommended, but may be necessary to support legacy job configurations.
Closes#9970
This PR adds default_pid_mode and default_ipc_mode options to the exec and java
task drivers. By default these will default to "private" mode, enabling PID and
IPC isolation for tasks. Setting them to "host" mode disables isolation. Doing
so is not recommended, but may be necessary to support legacy job configurations.
Closes#9969
