1xserver_selinux(8)          SELinux Policy xserver          xserver_selinux(8)
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NAME

6       xserver_selinux  -  Security Enhanced Linux Policy for the xserver pro‐
7       cesses
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DESCRIPTION

10       Security-Enhanced Linux secures  the  xserver  processes  via  flexible
11       mandatory access control.
12
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:
18
19       ps -eZ | grep xserver_t
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21
22

ENTRYPOINTS

24       The  xserver_t  SELinux type can be entered via the xserver_exec_t file
25       type.
26
27       The default entrypoint paths for the xserver_t domain are  the  follow‐
28       ing:
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30       /usr/bin/nvidia.*,    /usr/bin/Xair,    /usr/bin/Xorg,   /usr/bin/Xvnc,
31       /usr/bin/Xephyr,           /usr/bin/x11vnc,           /usr/X11R6/bin/X,
32       /usr/X11R6/bin/Xorg,    /usr/X11R6/bin/Xipaq,    /usr/libexec/Xorg.bin,
33       /usr/X11R6/bin/XFree86,  /usr/libexec/Xorg.wrap,  /usr/X11R6/bin/Xwrap‐
34       per, /usr/libexec/gsd-backlight-helper
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PROCESS TYPES

37       SELinux defines process types (domains) for each process running on the
38       system
39
40       You can see the context of a process using the -Z option to ps
41
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.
45
46       The following process types are defined for xserver:
47
48       xserver_t
49
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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55

BOOLEANS

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 allows XServer to execute writable memory, you must turn
65       on the xserver_execmem boolean. Disabled by default.
66
67       setsebool -P xserver_execmem 1
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71       If you want to support X userspace object manager, you must turn on the
72       xserver_object_manager boolean. Enabled by default.
73
74       setsebool -P xserver_object_manager 1
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78       If you want to allow users to resolve user passwd entries directly from
79       ldap  rather  then  using  a  sssd server, you must turn on the authlo‐
80       gin_nsswitch_use_ldap boolean. Disabled by default.
81
82       setsebool -P authlogin_nsswitch_use_ldap 1
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86       If you want to deny user domains applications to map a memory region as
87       both  executable  and  writable,  this  is dangerous and the executable
88       should be reported in bugzilla, you must turn on the deny_execmem bool‐
89       ean. Enabled by default.
90
91       setsebool -P deny_execmem 1
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95       If you want to allow all domains to execute in fips_mode, you must turn
96       on the fips_mode boolean. Enabled by default.
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98       setsebool -P fips_mode 1
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101
102       If you want to allow confined applications to run  with  kerberos,  you
103       must turn on the kerberos_enabled boolean. Enabled by default.
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105       setsebool -P kerberos_enabled 1
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107
108
109       If  you  want  to control the ability to mmap a low area of the address
110       space, as configured by /proc/sys/vm/mmap_min_addr, you  must  turn  on
111       the mmap_low_allowed boolean. Disabled by default.
112
113       setsebool -P mmap_low_allowed 1
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116
117       If  you  want  to  allow  system  to run with NIS, you must turn on the
118       nis_enabled boolean. Disabled by default.
119
120       setsebool -P nis_enabled 1
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122
123
124       If you want to allow confined applications to use nscd  shared  memory,
125       you must turn on the nscd_use_shm boolean. Enabled by default.
126
127       setsebool -P nscd_use_shm 1
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129
130
131       If  you  want  to  disable  kernel module loading, you must turn on the
132       secure_mode_insmod boolean. Enabled by default.
133
134       setsebool -P secure_mode_insmod 1
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137
138       If you want to allow unconfined executables to make their  heap  memory
139       executable.   Doing  this  is  a  really bad idea. Probably indicates a
140       badly coded executable, but could indicate an attack.  This  executable
141       should   be   reported  in  bugzilla,  you  must  turn  on  the  selin‐
142       uxuser_execheap boolean. Disabled by default.
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144       setsebool -P selinuxuser_execheap 1
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148       If you want to allow unconfined executables to make  their  stack  exe‐
149       cutable.   This  should  never, ever be necessary. Probably indicates a
150       badly coded executable, but could indicate an attack.  This  executable
151       should  be reported in bugzilla, you must turn on the selinuxuser_exec‐
152       stack boolean. Enabled by default.
153
154       setsebool -P selinuxuser_execstack 1
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156
157
158       If you want to allow confined  virtual  guests  to  interact  with  the
159       xserver,  you  must  turn  on the virt_use_xserver boolean. Disabled by
160       default.
161
162       setsebool -P virt_use_xserver 1
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165

PORT TYPES

167       SELinux defines port types to represent TCP and UDP ports.
168
169       You can see the types associated with a port  by  using  the  following
170       command:
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172       semanage port -l
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174
175       Policy  governs  the  access  confined  processes  have to these ports.
176       SELinux xserver policy is very flexible allowing users to  setup  their
177       xserver processes in as secure a method as possible.
178
179       The following port types are defined for xserver:
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181
182       xserver_port_t
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186       Default Defined Ports:
187                 tcp 6000-6020
188

MANAGED FILES

190       The  SELinux  process  type xserver_t can manage files labeled with the
191       following file types.  The paths listed are the default paths for these
192       file types.  Note the processes UID still need to have DAC permissions.
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194       file_type
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196            all files on the system
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198

FILE CONTEXTS

200       SELinux requires files to have an extended attribute to define the file
201       type.
202
203       You can see the context of a file using the -Z option to ls
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205       Policy governs the access  confined  processes  have  to  these  files.
206       SELinux  xserver  policy is very flexible allowing users to setup their
207       xserver processes in as secure a method as possible.
208
209       STANDARD FILE CONTEXT
210
211       SELinux defines the file context types for the xserver, if  you  wanted
212       to store files with these types in a diffent paths, you need to execute
213       the semanage command  to  sepecify  alternate  labeling  and  then  use
214       restorecon to put the labels on disk.
215
216       semanage fcontext -a -t xserver_log_t '/srv/myxserver_content(/.*)?'
217       restorecon -R -v /srv/myxserver_content
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219       Note:  SELinux  often  uses  regular expressions to specify labels that
220       match multiple files.
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222       The following file types are defined for xserver:
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226       xserver_etc_t
227
228       - Set files with the xserver_etc_t type, if you want to  store  xserver
229       files in the /etc directories.
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233       xserver_exec_t
234
235       -  Set files with the xserver_exec_t type, if you want to transition an
236       executable to the xserver_t domain.
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239       Paths:
240            /usr/bin/nvidia.*,  /usr/bin/Xair,  /usr/bin/Xorg,  /usr/bin/Xvnc,
241            /usr/bin/Xephyr,         /usr/bin/x11vnc,        /usr/X11R6/bin/X,
242            /usr/X11R6/bin/Xorg, /usr/X11R6/bin/Xipaq,  /usr/libexec/Xorg.bin,
243            /usr/X11R6/bin/XFree86,                    /usr/libexec/Xorg.wrap,
244            /usr/X11R6/bin/Xwrapper, /usr/libexec/gsd-backlight-helper
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247       xserver_log_t
248
249       - Set files with the xserver_log_t type, if you want to treat the  data
250       as xserver log data, usually stored under the /var/log directory.
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252
253       Paths:
254            /var/[xgkw]dm(/.*)?,                      /usr/var/[xgkw]dm(/.*)?,
255            /var/log/gdm(3)?(/.*)?,    /var/log/Xorg.*,    /var/log/XFree86.*,
256            /var/log/lightdm(/.*)?, /var/log/nvidia-installer.log.*
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259       xserver_tmpfs_t
260
261       - Set files with the xserver_tmpfs_t type, if you want to store xserver
262       files on a tmpfs file system.
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266       xserver_var_lib_t
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268       - Set files with the xserver_var_lib_t type, if you want to  store  the
269       xserver files under the /var/lib directory.
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272
273       xserver_var_run_t
274
275       -  Set  files with the xserver_var_run_t type, if you want to store the
276       xserver files under the /run or /var/run directory.
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278
279       Paths:
280            /var/run/xorg(/.*)?, /var/run/video.rom
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282
283       Note: File context can be temporarily modified with the chcon  command.
284       If  you want to permanently change the file context you need to use the
285       semanage fcontext command.  This will modify the SELinux labeling data‐
286       base.  You will need to use restorecon to apply the labels.
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288

COMMANDS

290       semanage  fcontext  can also be used to manipulate default file context
291       mappings.
292
293       semanage permissive can also be used to manipulate  whether  or  not  a
294       process type is permissive.
295
296       semanage  module can also be used to enable/disable/install/remove pol‐
297       icy modules.
298
299       semanage port can also be used to manipulate the port definitions
300
301       semanage boolean can also be used to manipulate the booleans
302
303
304       system-config-selinux is a GUI tool available to customize SELinux pol‐
305       icy settings.
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307

AUTHOR

309       This manual page was auto-generated using sepolicy manpage .
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SEE ALSO

313       selinux(8),  xserver(8),  semanage(8),  restorecon(8), chcon(1), sepol‐
314       icy(8), setsebool(8)
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318xserver                            19-10-08                 xserver_selinux(8)
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