1xserver_selinux(8) SELinux Policy xserver xserver_selinux(8)
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6 xserver_selinux - Security Enhanced Linux Policy for the xserver pro‐
7 cesses
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10 Security-Enhanced Linux secures the xserver processes via flexible
11 mandatory access control.
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13 The xserver processes execute with the xserver_t SELinux type. You can
14 check if you have these processes running by executing the ps command
15 with the -Z qualifier.
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17 For example:
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19 ps -eZ | grep xserver_t
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24 The xserver_t SELinux type can be entered via the file_type, unla‐
25 beled_t, proc_type, xserver_exec_t, filesystem_type, mtrr_device_t,
26 sysctl_type file types.
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28 The default entrypoint paths for the xserver_t domain are the follow‐
29 ing:
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31 all files on the system, /usr/bin/Xair, /usr/bin/Xorg, /usr/bin/Xephyr,
32 /usr/X11R6/bin/X, /usr/X11R6/bin/Xorg, /usr/X11R6/bin/Xipaq,
33 /usr/local/bin/x11vnc, /usr/X11R6/bin/XFree86, /usr/X11R6/bin/Xwrapper,
34 /etc/init.d/xfree86-common, /dev/cpu/mtrr
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37 SELinux defines process types (domains) for each process running on the
38 system
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40 You can see the context of a process using the -Z option to ps
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42 Policy governs the access confined processes have to files. SELinux
43 xserver policy is very flexible allowing users to setup their xserver
44 processes in as secure a method as possible.
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46 The following process types are defined for xserver:
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48 xserver_t
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50 Note: semanage permissive -a xserver_t can be used to make the process
51 type xserver_t permissive. SELinux does not deny access to permissive
52 process types, but the AVC (SELinux denials) messages are still gener‐
53 ated.
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57 SELinux policy is customizable based on least access required. xserver
58 policy is extremely flexible and has several booleans that allow you to
59 manipulate the policy and run xserver with the tightest access possi‐
60 ble.
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64 If you want to support X userspace object manager, you must turn on the
65 xserver_object_manager boolean. Disabled by default.
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67 setsebool -P xserver_object_manager 1
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71 If you want to allow all daemons the ability to read/write terminals,
72 you must turn on the allow_daemons_use_tty boolean. Disabled by
73 default.
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75 setsebool -P allow_daemons_use_tty 1
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79 If you want to allow all domains to use other domains file descriptors,
80 you must turn on the allow_domain_fd_use boolean. Enabled by default.
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82 setsebool -P allow_domain_fd_use 1
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86 If you want to allow unconfined executables to make their heap memory
87 executable. Doing this is a really bad idea. Probably indicates a
88 badly coded executable, but could indicate an attack. This executable
89 should be reported in bugzilla, you must turn on the allow_execheap
90 boolean. Disabled by default.
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92 setsebool -P allow_execheap 1
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96 If you want to allow unconfined executables to map a memory region as
97 both executable and writable, this is dangerous and the executable
98 should be reported in bugzilla), you must turn on the allow_execmem
99 boolean. Enabled by default.
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101 setsebool -P allow_execmem 1
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105 If you want to allow all unconfined executables to use libraries
106 requiring text relocation that are not labeled textrel_shlib_t), you
107 must turn on the allow_execmod boolean. Enabled by default.
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109 setsebool -P allow_execmod 1
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113 If you want to allow unconfined executables to make their stack exe‐
114 cutable. This should never, ever be necessary. Probably indicates a
115 badly coded executable, but could indicate an attack. This executable
116 should be reported in bugzilla), you must turn on the allow_execstack
117 boolean. Enabled by default.
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119 setsebool -P allow_execstack 1
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123 If you want to allow confined applications to run with kerberos, you
124 must turn on the allow_kerberos boolean. Enabled by default.
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126 setsebool -P allow_kerberos 1
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130 If you want to allow sysadm to debug or ptrace all processes, you must
131 turn on the allow_ptrace boolean. Disabled by default.
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133 setsebool -P allow_ptrace 1
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137 If you want to allows XServer to execute writable memory, you must turn
138 on the allow_xserver_execmem boolean. Disabled by default.
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140 setsebool -P allow_xserver_execmem 1
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144 If you want to allow system to run with NIS, you must turn on the
145 allow_ypbind boolean. Disabled by default.
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147 setsebool -P allow_ypbind 1
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151 If you want to allow all domains to have the kernel load modules, you
152 must turn on the domain_kernel_load_modules boolean. Disabled by
153 default.
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155 setsebool -P domain_kernel_load_modules 1
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159 If you want to allow all domains to execute in fips_mode, you must turn
160 on the fips_mode boolean. Enabled by default.
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162 setsebool -P fips_mode 1
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166 If you want to enable reading of urandom for all domains, you must turn
167 on the global_ssp boolean. Disabled by default.
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169 setsebool -P global_ssp 1
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173 If you want to allow certain domains to map low memory in the kernel,
174 you must turn on the mmap_low_allowed boolean. Disabled by default.
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176 setsebool -P mmap_low_allowed 1
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180 If you want to allow confined applications to use nscd shared memory,
181 you must turn on the nscd_use_shm boolean. Enabled by default.
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183 setsebool -P nscd_use_shm 1
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187 If you want to disable transitions to insmod, you must turn on the
188 secure_mode_insmod boolean. Disabled by default.
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190 setsebool -P secure_mode_insmod 1
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194 If you want to boolean to determine whether the system permits loading
195 policy, setting enforcing mode, and changing boolean values. Set this
196 to true and you have to reboot to set it back, you must turn on the
197 secure_mode_policyload boolean. Disabled by default.
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199 setsebool -P secure_mode_policyload 1
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203 If you want to support NFS home directories, you must turn on the
204 use_nfs_home_dirs boolean. Disabled by default.
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206 setsebool -P use_nfs_home_dirs 1
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210 If you want to support SAMBA home directories, you must turn on the
211 use_samba_home_dirs boolean. Disabled by default.
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213 setsebool -P use_samba_home_dirs 1
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218 SELinux defines port types to represent TCP and UDP ports.
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220 You can see the types associated with a port by using the following
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223 semanage port -l
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226 Policy governs the access confined processes have to these ports.
227 SELinux xserver policy is very flexible allowing users to setup their
228 xserver processes in as secure a method as possible.
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230 The following port types are defined for xserver:
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233 xserver_port_t
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237 Default Defined Ports:
238 tcp 6000-6150
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241 The SELinux process type xserver_t can manage files labeled with the
242 following file types. The paths listed are the default paths for these
243 file types. Note the processes UID still need to have DAC permissions.
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245 file_type
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247 all files on the system
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251 SELinux requires files to have an extended attribute to define the file
252 type.
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254 You can see the context of a file using the -Z option to ls
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256 Policy governs the access confined processes have to these files.
257 SELinux xserver policy is very flexible allowing users to setup their
258 xserver processes in as secure a method as possible.
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260 STANDARD FILE CONTEXT
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262 SELinux defines the file context types for the xserver, if you wanted
263 to store files with these types in a diffent paths, you need to execute
264 the semanage command to sepecify alternate labeling and then use
265 restorecon to put the labels on disk.
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267 semanage fcontext -a -t xserver_var_run_t '/srv/myxserver_con‐
268 tent(/.*)?'
269 restorecon -R -v /srv/myxserver_content
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271 Note: SELinux often uses regular expressions to specify labels that
272 match multiple files.
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274 The following file types are defined for xserver:
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278 xserver_exec_t
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280 - Set files with the xserver_exec_t type, if you want to transition an
281 executable to the xserver_t domain.
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284 Paths:
285 /usr/bin/Xair, /usr/bin/Xorg, /usr/bin/Xephyr, /usr/X11R6/bin/X,
286 /usr/X11R6/bin/Xorg, /usr/X11R6/bin/Xipaq, /usr/local/bin/x11vnc,
287 /usr/X11R6/bin/XFree86, /usr/X11R6/bin/Xwrapper,
288 /etc/init.d/xfree86-common
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291 xserver_log_t
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293 - Set files with the xserver_log_t type, if you want to treat the data
294 as xserver log data, usually stored under the /var/log directory.
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297 Paths:
298 /var/[xgk]dm(/.*)?, /var/log/[kw]dm.log.*,
299 /usr/var/[xgkw]dm(/.*)?, /var/log/Xorg.*, /var/log/XFree86.*,
300 /var/log/nvidia-installer.log.*
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303 xserver_tmpfs_t
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305 - Set files with the xserver_tmpfs_t type, if you want to store xserver
306 files on a tmpfs file system.
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310 xserver_var_lib_t
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312 - Set files with the xserver_var_lib_t type, if you want to store the
313 xserver files under the /var/lib directory.
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317 xserver_var_run_t
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319 - Set files with the xserver_var_run_t type, if you want to store the
320 xserver files under the /run or /var/run directory.
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323 Paths:
324 /var/run/xorg(/.*)?, /var/run/video.rom
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327 Note: File context can be temporarily modified with the chcon command.
328 If you want to permanently change the file context you need to use the
329 semanage fcontext command. This will modify the SELinux labeling data‐
330 base. You will need to use restorecon to apply the labels.
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334 semanage fcontext can also be used to manipulate default file context
335 mappings.
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337 semanage permissive can also be used to manipulate whether or not a
338 process type is permissive.
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340 semanage module can also be used to enable/disable/install/remove pol‐
341 icy modules.
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343 semanage port can also be used to manipulate the port definitions
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345 semanage boolean can also be used to manipulate the booleans
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348 system-config-selinux is a GUI tool available to customize SELinux pol‐
349 icy settings.
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353 This manual page was auto-generated using sepolicy manpage .
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357 selinux(8), xserver(8), semanage(8), restorecon(8), chcon(1) , setse‐
358 bool(8)
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362xserver 15-06-03 xserver_selinux(8)