Security-Enhanced Linux secures the sandbox_xserver processes via flexible mandatory access control.
The sandbox_xserver processes execute with the sandbox_xserver_t SELinux type. You can check if you have these processes running by executing the ps command with the -Z qualifier.
ps -eZ | grep sandbox_xserver_t
The sandbox_xserver_t SELinux type can be entered via the xserver_exec_t file type.
The default entrypoint paths for the sandbox_xserver_t domain are the following:
/usr/bin/nvidia.*, /usr/bin/Xair, /usr/bin/Xorg, /usr/bin/Xvnc, /usr/bin/Xephyr, /usr/bin/x11vnc, /usr/X11R6/bin/X, /usr/bin/Xwayland, /usr/X11R6/bin/Xorg, /usr/X11R6/bin/Xipaq, /usr/libexec/Xorg.bin, /usr/X11R6/bin/XFree86, /usr/libexec/Xorg.wrap, /usr/X11R6/bin/Xwrapper, /usr/libexec/gsd-backlight-helper
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 psbP
Policy governs the access confined processes have to files. SELinux sandbox_xserver policy is very flexible allowing users to setup their sandbox_xserver processes in as secure a method as possible.
The following process types are defined for sandbox_xserver:
Note: semanage permissive -a sandbox_xserver_t can be used to make the process type sandbox_xserver_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. sandbox_xserver policy is extremely flexible and has several booleans that allow you to manipulate the policy and run sandbox_xserver with the tightest access possible.
If you want to deny user domains applications to map a memory region as both executable and writable, this is dangerous and the executable should be reported in bugzilla, you must turn on the deny_execmem boolean. Enabled by default.
setsebool -P deny_execmem 1
If you want to allow regular users direct dri device access, you must turn on the selinuxuser_direct_dri_enabled boolean. Enabled by default.
setsebool -P selinuxuser_direct_dri_enabled 1
If you want to support fusefs home directories, you must turn on the use_fusefs_home_dirs boolean. Disabled by default.
setsebool -P use_fusefs_home_dirs 1
If you want to support NFS home directories, you must turn on the use_nfs_home_dirs boolean. Disabled by default.
setsebool -P use_nfs_home_dirs 1
If you want to support SAMBA home directories, you must turn on the use_samba_home_dirs boolean. Disabled by default.
setsebool -P use_samba_home_dirs 1
If you want to allows clients to write to the X server shared memory segments, you must turn on the xserver_clients_write_xshm boolean. Disabled by default.
setsebool -P xserver_clients_write_xshm 1
The SELinux process type sandbox_xserver_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.
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), sandbox_xserver(8), semanage(8), restorecon(8), chcon(1), sepolicy(8), setsebool(8)