Security-Enhanced Linux secures the sge_job processes via flexible mandatory access control.
The sge_job processes execute with the sge_job_t SELinux type. You can check if you have these processes running by executing the ps command with the -Z qualifier.
ps -eZ | grep sge_job_t
The sge_job_t SELinux type can be entered via the shell_exec_t, sge_job_exec_t file types.
The default entrypoint paths for the sge_job_t domain are the following:
/bin/d?ash, /bin/ksh.*, /bin/zsh.*, /usr/bin/d?ash, /usr/bin/ksh.*, /usr/bin/zsh.*, /bin/esh, /bin/bash, /bin/fish, /bin/mksh, /bin/sash, /bin/tcsh, /bin/yash, /bin/bash2, /usr/bin/esh, /sbin/nologin, /usr/bin/bash, /usr/bin/fish, /usr/bin/mksh, /usr/bin/sash, /usr/bin/tcsh, /usr/bin/yash, /usr/bin/bash2, /usr/sbin/sesh, /usr/sbin/smrsh, /usr/bin/scponly, /usr/libexec/sesh, /usr/sbin/nologin, /usr/bin/git-shell, /usr/sbin/scponlyc, /usr/libexec/sudo/sesh, /usr/bin/cockpit-bridge, /usr/libexec/cockpit-agent, /usr/libexec/git-core/git-shell
You can see the context of a process using the -Z option to psP Policy governs the access confined processes have to files. SELinux sge_job policy is very flexible allowing users to setup their sge_job processes in as secure a method as possible.
The following process types are defined for sge_job:
Note: semanage permissive -a sge_job_t can be used to make the process type sge_job_t permissive. SELinux does not deny access to permissive process types, but the AVC (SELinux denials) messages are still generated.
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. Disabled by default.
setsebool -P deny_execmem 1
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
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 allow confined applications to use nscd shared memory, you must turn on the nscd_use_shm boolean. Enabled by default.
setsebool -P nscd_use_shm 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
If you want to allow unconfined executables to make their heap memory executable. Doing this is a really bad idea. Probably indicates a badly coded executable, but could indicate an attack. This executable should be reported in bugzilla, you must turn on the selinuxuser_execheap boolean. Disabled by default.
setsebool -P selinuxuser_execheap 1
If you want to allow unconfined executables to make their stack executable. This should never, ever be necessary. Probably indicates a badly coded executable, but could indicate an attack. This executable should be reported in bugzilla, you must turn on the selinuxuser_execstack boolean. Enabled by default.
setsebool -P selinuxuser_execstack 1
The SELinux process type sge_job_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.
all files on the system
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.