Security-Enhanced Linux secures the dmesg processes via flexible mandatory access control.
The dmesg processes execute with the dmesg_t SELinux type. You can check if you have these processes running by executing the ps command with the -Z qualifier.
ps -eZ | grep dmesg_t
The dmesg_t SELinux type can be entered via the dmesg_exec_t file type.
The default entrypoint paths for the dmesg_t domain are the following:
You can see the context of a process using the -Z option to psP Policy governs the access confined processes have to files. SELinux dmesg policy is very flexible allowing users to setup their dmesg processes in as secure a method as possible.
The following process types are defined for dmesg:
Note: semanage permissive -a dmesg_t can be used to make the process type dmesg_t permissive. SELinux does not deny access to permissive process types, but the AVC (SELinux denials) messages are still generated.
If you want to allow all domains to execute in fips_mode, you must turn on the fips_mode boolean. Enabled by default.
setsebool -P fips_mode 1
The SELinux process type dmesg_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.
You can see the context of a file using the -Z option to lsP Policy governs the access confined processes have to these files. SELinux dmesg policy is very flexible allowing users to setup their dmesg processes in as secure a method as possible.
The following file types are defined for dmesg:
- Set files with the dmesg_exec_t type, if you want to transition an executable to the dmesg_t domain.
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 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.