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 prelink_exec_t file
25 type.
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27 The default entrypoint paths for the prelink_t domain are the follow‐
28 ing:
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30 /usr/sbin/prelink(.bin)?
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33 SELinux defines process types (domains) for each process running on the
34 system
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36 You can see the context of a process using the -Z option to ps
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38 Policy governs the access confined processes have to files. SELinux
39 prelink policy is very flexible allowing users to setup their prelink
40 processes in as secure a method as possible.
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42 The following process types are defined for prelink:
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44 prelink_t, prelink_cron_system_t
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46 Note: semanage permissive -a prelink_t can be used to make the process
47 type prelink_t permissive. SELinux does not deny access to permissive
48 process types, but the AVC (SELinux denials) messages are still gener‐
49 ated.
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53 SELinux policy is customizable based on least access required. prelink
54 policy is extremely flexible and has several booleans that allow you to
55 manipulate the policy and run prelink with the tightest access possi‐
56 ble.
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60 If you want to control the ability to mmap a low area of the address
61 space, as configured by /proc/sys/vm/mmap_min_addr, you must turn on
62 the mmap_low_allowed boolean. Disabled by default.
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64 setsebool -P mmap_low_allowed 1
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68 If you want to disable kernel module loading, you must turn on the se‐
69 cure_mode_insmod boolean. Disabled by default.
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71 setsebool -P secure_mode_insmod 1
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76 The SELinux process type prelink_t can manage files labeled with the
77 following file types. The paths listed are the default paths for these
78 file types. Note the processes UID still need to have DAC permissions.
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80 file_type
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82 all files on the system
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86 SELinux requires files to have an extended attribute to define the file
87 type.
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89 You can see the context of a file using the -Z option to ls
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91 Policy governs the access confined processes have to these files.
92 SELinux prelink policy is very flexible allowing users to setup their
93 prelink processes in as secure a method as possible.
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95 EQUIVALENCE DIRECTORIES
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98 prelink policy stores data with multiple different file context types
99 under the /var/log/prelink directory. If you would like to store the
100 data in a different directory you can use the semanage command to cre‐
101 ate an equivalence mapping. If you wanted to store this data under the
102 /srv directory you would execute the following command:
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104 semanage fcontext -a -e /var/log/prelink /srv/prelink
105 restorecon -R -v /srv/prelink
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107 STANDARD FILE CONTEXT
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109 SELinux defines the file context types for the prelink, if you wanted
110 to store files with these types in a different paths, you need to exe‐
111 cute the semanage command to specify alternate labeling and then use
112 restorecon to put the labels on disk.
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114 semanage fcontext -a -t prelink_exec_t '/srv/prelink/content(/.*)?'
115 restorecon -R -v /srv/myprelink_content
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117 Note: SELinux often uses regular expressions to specify labels that
118 match multiple files.
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120 The following file types are defined for prelink:
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124 prelink_cache_t
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126 - Set files with the prelink_cache_t type, if you want to store the
127 files under the /var/cache directory.
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131 prelink_cron_system_exec_t
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133 - Set files with the prelink_cron_system_exec_t type, if you want to
134 transition an executable to the prelink_cron_system_t domain.
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138 prelink_exec_t
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140 - Set files with the prelink_exec_t type, if you want to transition an
141 executable to the prelink_t domain.
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145 prelink_log_t
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147 - Set files with the prelink_log_t type, if you want to treat the data
148 as prelink log data, usually stored under the /var/log directory.
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151 Paths:
152 /var/log/prelink(/.*)?, /var/log/prelink.log.*
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155 prelink_tmp_t
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157 - Set files with the prelink_tmp_t type, if you want to store prelink
158 temporary files in the /tmp directories.
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162 prelink_tmpfs_t
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164 - Set files with the prelink_tmpfs_t type, if you want to store prelink
165 files on a tmpfs file system.
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169 prelink_var_lib_t
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171 - Set files with the prelink_var_lib_t type, if you want to store the
172 prelink files under the /var/lib directory.
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175 Paths:
176 /var/lib/prelink(/.*)?, /var/lib/misc/prelink.*
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179 Note: File context can be temporarily modified with the chcon command.
180 If you want to permanently change the file context you need to use the
181 semanage fcontext command. This will modify the SELinux labeling data‐
182 base. You will need to use restorecon to apply the labels.
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186 semanage fcontext can also be used to manipulate default file context
187 mappings.
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189 semanage permissive can also be used to manipulate whether or not a
190 process type is permissive.
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192 semanage module can also be used to enable/disable/install/remove pol‐
193 icy modules.
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195 semanage boolean can also be used to manipulate the booleans
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198 system-config-selinux is a GUI tool available to customize SELinux pol‐
199 icy settings.
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203 This manual page was auto-generated using sepolicy manpage .
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207 selinux(8), prelink(8), semanage(8), restorecon(8), chcon(1), sepol‐
208 icy(8), setsebool(8), prelink_cron_system_selinux(8), prelink_cron_sys‐
209 tem_selinux(8)
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213prelink 23-10-20 prelink_selinux(8)