kubelet_selinux − Security Enhanced Linux Policy for the kubelet processes
Security-Enhanced Linux secures the kubelet processes via flexible mandatory access control.
The kubelet processes execute with the kubelet_t SELinux type. You can check if you have these processes running by executing the ps command with the −Z qualifier.
For example:
ps -eZ | grep kubelet_t
The kubelet_t SELinux type can be entered via the kubelet_exec_t file type.
The default entrypoint paths for the kubelet_t domain are the following:
/usr/s?bin/kubelet.*, /usr/s?bin/hyperkube.*, /usr/s?bin/kubensenter.*, /usr/s?bin/kubenswrapper.*, /usr/local/s?bin/kubelet.*, /usr/local/s?bin/hyperkube.*, /usr/local/s?bin/kubensenter.*, /usr/local/s?bin/kubenswrapper.*
SELinux defines process types (domains) for each process running on the system
You can see the context of a process using the −Z option to ps
Policy governs the access confined processes have to files. SELinux kubelet policy is very flexible allowing users to setup their kubelet processes in as secure a method as possible.
The following process types are defined for kubelet:
kubelet_t
Note: semanage permissive -a kubelet_t can be used to make the process type kubelet_t permissive. SELinux does not deny access to permissive process types, but the AVC (SELinux denials) messages are still generated.
SELinux policy is customizable based on least access required. kubelet policy is extremely flexible and has several booleans that allow you to manipulate the policy and run kubelet with the tightest access possible.
If you want to dontaudit all daemons scheduling requests (setsched, sys_nice), you must turn on the daemons_dontaudit_scheduling boolean. Enabled by default.
setsebool -P daemons_dontaudit_scheduling 1
If you want to control the ability to mmap a low area of the address space, as configured by /proc/sys/vm/mmap_min_addr, you must turn on the mmap_low_allowed boolean. Disabled by default.
setsebool -P mmap_low_allowed 1
If you want to disable kernel module loading, you must turn on the secure_mode_insmod boolean. Disabled by default.
setsebool -P secure_mode_insmod 1
The SELinux process type kubelet_t can manage files labeled with the following file types. The paths listed are the default paths for these file types. Note the processes UID still need to have DAC permissions.
file_type
all files on the system
SELinux requires files to have an extended attribute to define the file type.
You can see the context of a file using the −Z option to ls
Policy governs the access confined processes have to these files. SELinux kubelet policy is very flexible allowing users to setup their kubelet processes in as secure a method as possible.
The following file types are defined for kubelet:
kubelet_exec_t
- Set files
with the kubelet_exec_t type, if you want to transition an
executable to the kubelet_t domain.
Paths:
/usr/s?bin/kubelet.*, /usr/s?bin/hyperkube.*, /usr/s?bin/kubensenter.*, /usr/s?bin/kubenswrapper.*, /usr/local/s?bin/kubelet.*, /usr/local/s?bin/hyperkube.*, /usr/local/s?bin/kubensenter.*, /usr/local/s?bin/kubenswrapper.*
Note: File context can be temporarily modified with the chcon command. If you want to permanently change the file context you need to use the semanage fcontext command. This will modify the SELinux labeling database. You will need to use restorecon to apply the labels.
semanage fcontext can also be used to manipulate default file context mappings.
semanage permissive can also be used to manipulate whether or not a process type is permissive.
semanage module can also be used to enable/disable/install/remove policy modules.
semanage boolean can also be used to manipulate the booleans
system-config-selinux is a GUI tool available to customize SELinux policy settings.
This manual page was auto-generated using sepolicy manpage .
selinux(8), kubelet(8), semanage(8), restorecon(8), chcon(1), sepolicy(8), setsebool(8)