1prelink_selinux(8) SELinux Policy prelink prelink_selinux(8)
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6 prelink_selinux - Security Enhanced Linux Policy for the prelink pro‐
7 cesses
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10 Security-Enhanced Linux secures the prelink processes via flexible
11 mandatory access control.
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13 The prelink processes execute with the prelink_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 prelink_t
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24 The prelink_t SELinux type can be entered via the file_type, pre‐
25 link_exec_t, unlabeled_t, proc_type, filesystem_type, mtrr_device_t,
26 sysctl_type file types.
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28 The default entrypoint paths for the prelink_t domain are the follow‐
29 ing:
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31 all files on the system, /usr/sbin/prelink(.bin)?, /dev/cpu/mtrr
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34 SELinux defines process types (domains) for each process running on the
35 system
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37 You can see the context of a process using the -Z option to ps
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39 Policy governs the access confined processes have to files. SELinux
40 prelink policy is very flexible allowing users to setup their prelink
41 processes in as secure a method as possible.
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43 The following process types are defined for prelink:
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45 prelink_mask_t, prelink_cron_system_t, prelink_t
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47 Note: semanage permissive -a prelink_t can be used to make the process
48 type prelink_t permissive. SELinux does not deny access to permissive
49 process types, but the AVC (SELinux denials) messages are still gener‐
50 ated.
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54 SELinux policy is customizable based on least access required. prelink
55 policy is extremely flexible and has several booleans that allow you to
56 manipulate the policy and run prelink with the tightest access possi‐
57 ble.
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61 If you want to allow all daemons the ability to read/write terminals,
62 you must turn on the allow_daemons_use_tty boolean. Disabled by
63 default.
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65 setsebool -P allow_daemons_use_tty 1
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69 If you want to allow all domains to use other domains file descriptors,
70 you must turn on the allow_domain_fd_use boolean. Enabled by default.
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72 setsebool -P allow_domain_fd_use 1
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76 If you want to allow unconfined executables to make their heap memory
77 executable. Doing this is a really bad idea. Probably indicates a
78 badly coded executable, but could indicate an attack. This executable
79 should be reported in bugzilla, you must turn on the allow_execheap
80 boolean. Disabled by default.
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82 setsebool -P allow_execheap 1
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86 If you want to allow unconfined executables 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 allow_execmem
89 boolean. Enabled by default.
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91 setsebool -P allow_execmem 1
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95 If you want to allow all unconfined executables to use libraries
96 requiring text relocation that are not labeled textrel_shlib_t), you
97 must turn on the allow_execmod boolean. Enabled by default.
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99 setsebool -P allow_execmod 1
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103 If you want to allow unconfined executables to make their stack exe‐
104 cutable. This should never, ever be necessary. Probably indicates a
105 badly coded executable, but could indicate an attack. This executable
106 should be reported in bugzilla), you must turn on the allow_execstack
107 boolean. Enabled by default.
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109 setsebool -P allow_execstack 1
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113 If you want to allow sysadm to debug or ptrace all processes, you must
114 turn on the allow_ptrace boolean. Disabled by default.
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116 setsebool -P allow_ptrace 1
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120 If you want to allow all domains to have the kernel load modules, you
121 must turn on the domain_kernel_load_modules boolean. Disabled by
122 default.
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124 setsebool -P domain_kernel_load_modules 1
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128 If you want to allow all domains to execute in fips_mode, you must turn
129 on the fips_mode boolean. Enabled by default.
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131 setsebool -P fips_mode 1
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135 If you want to enable reading of urandom for all domains, you must turn
136 on the global_ssp boolean. Disabled by default.
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138 setsebool -P global_ssp 1
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142 If you want to allow certain domains to map low memory in the kernel,
143 you must turn on the mmap_low_allowed boolean. Disabled by default.
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145 setsebool -P mmap_low_allowed 1
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149 If you want to boolean to determine whether the system permits loading
150 policy, setting enforcing mode, and changing boolean values. Set this
151 to true and you have to reboot to set it back, you must turn on the
152 secure_mode_policyload boolean. Disabled by default.
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154 setsebool -P secure_mode_policyload 1
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158 If you want to support X userspace object manager, you must turn on the
159 xserver_object_manager boolean. Disabled by default.
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161 setsebool -P xserver_object_manager 1
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166 The SELinux process type prelink_t can manage files labeled with the
167 following file types. The paths listed are the default paths for these
168 file types. Note the processes UID still need to have DAC permissions.
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170 file_type
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172 all files on the system
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176 SELinux requires files to have an extended attribute to define the file
177 type.
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179 You can see the context of a file using the -Z option to ls
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181 Policy governs the access confined processes have to these files.
182 SELinux prelink policy is very flexible allowing users to setup their
183 prelink processes in as secure a method as possible.
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185 EQUIVALENCE DIRECTORIES
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188 prelink policy stores data with multiple different file context types
189 under the /var/log/prelink directory. If you would like to store the
190 data in a different directory you can use the semanage command to cre‐
191 ate an equivalence mapping. If you wanted to store this data under the
192 /srv dirctory you would execute the following command:
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194 semanage fcontext -a -e /var/log/prelink /srv/prelink
195 restorecon -R -v /srv/prelink
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197 STANDARD FILE CONTEXT
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199 SELinux defines the file context types for the prelink, if you wanted
200 to store files with these types in a diffent paths, you need to execute
201 the semanage command to sepecify alternate labeling and then use
202 restorecon to put the labels on disk.
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204 semanage fcontext -a -t prelink_var_lib_t '/srv/myprelink_con‐
205 tent(/.*)?'
206 restorecon -R -v /srv/myprelink_content
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208 Note: SELinux often uses regular expressions to specify labels that
209 match multiple files.
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211 The following file types are defined for prelink:
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215 prelink_cache_t
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217 - Set files with the prelink_cache_t type, if you want to store the
218 files under the /var/cache directory.
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222 prelink_cron_system_exec_t
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224 - Set files with the prelink_cron_system_exec_t type, if you want to
225 transition an executable to the prelink_cron_system_t domain.
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229 prelink_exec_t
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231 - Set files with the prelink_exec_t type, if you want to transition an
232 executable to the prelink_t domain.
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236 prelink_log_t
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238 - Set files with the prelink_log_t type, if you want to treat the data
239 as prelink log data, usually stored under the /var/log directory.
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242 Paths:
243 /var/log/prelink(/.*)?, /var/log/prelink.log.*
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246 prelink_tmp_t
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248 - Set files with the prelink_tmp_t type, if you want to store prelink
249 temporary files in the /tmp directories.
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253 prelink_tmpfs_t
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255 - Set files with the prelink_tmpfs_t type, if you want to store prelink
256 files on a tmpfs file system.
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260 prelink_var_lib_t
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262 - Set files with the prelink_var_lib_t type, if you want to store the
263 prelink files under the /var/lib directory.
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266 Paths:
267 /var/lib/prelink(/.*)?, /var/lib/misc/prelink.*
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270 Note: File context can be temporarily modified with the chcon command.
271 If you want to permanently change the file context you need to use the
272 semanage fcontext command. This will modify the SELinux labeling data‐
273 base. You will need to use restorecon to apply the labels.
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277 semanage fcontext can also be used to manipulate default file context
278 mappings.
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280 semanage permissive can also be used to manipulate whether or not a
281 process type is permissive.
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283 semanage module can also be used to enable/disable/install/remove pol‐
284 icy modules.
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286 semanage boolean can also be used to manipulate the booleans
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289 system-config-selinux is a GUI tool available to customize SELinux pol‐
290 icy settings.
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294 This manual page was auto-generated using sepolicy manpage .
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298 selinux(8), prelink(8), semanage(8), restorecon(8), chcon(1) , setse‐
299 bool(8), prelink_cron_system_selinux(8), prelink_cron_sys‐
300 tem_selinux(8), prelink_mask_selinux(8), prelink_mask_selinux(8)
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304prelink 15-06-03 prelink_selinux(8)