1dmesg_selinux(8) SELinux Policy dmesg dmesg_selinux(8)
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6 dmesg_selinux - Security Enhanced Linux Policy for the dmesg processes
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9 Security-Enhanced Linux secures the dmesg processes via flexible manda‐
10 tory access control.
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12 The dmesg processes execute with the dmesg_t SELinux type. You can
13 check if you have these processes running by executing the ps command
14 with the -Z qualifier.
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16 For example:
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18 ps -eZ | grep dmesg_t
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23 The dmesg_t SELinux type can be entered via the dmesg_exec_t file type.
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25 The default entrypoint paths for the dmesg_t domain are the following:
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27 /bin/dmesg, /usr/bin/dmesg
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30 SELinux defines process types (domains) for each process running on the
31 system
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33 You can see the context of a process using the -Z option to ps
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35 Policy governs the access confined processes have to files. SELinux
36 dmesg policy is very flexible allowing users to setup their dmesg pro‐
37 cesses in as secure a method as possible.
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39 The following process types are defined for dmesg:
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41 dmesg_t
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43 Note: semanage permissive -a dmesg_t can be used to make the process
44 type dmesg_t permissive. SELinux does not deny access to permissive
45 process types, but the AVC (SELinux denials) messages are still gener‐
46 ated.
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50 SELinux policy is customizable based on least access required. dmesg
51 policy is extremely flexible and has several booleans that allow you to
52 manipulate the policy and run dmesg with the tightest access possible.
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56 If you want to allow all daemons the ability to read/write terminals,
57 you must turn on the daemons_use_tty boolean. Disabled by default.
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59 setsebool -P daemons_use_tty 1
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63 If you want to deny any process from ptracing or debugging any other
64 processes, you must turn on the deny_ptrace boolean. Enabled by
65 default.
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67 setsebool -P deny_ptrace 1
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71 If you want to allow any process to mmap any file on system with
72 attribute file_type, you must turn on the domain_can_mmap_files bool‐
73 ean. Enabled by default.
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75 setsebool -P domain_can_mmap_files 1
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79 If you want to allow all domains write to kmsg_device, while kernel is
80 executed with systemd.log_target=kmsg parameter, you must turn on the
81 domain_can_write_kmsg boolean. Disabled by default.
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83 setsebool -P domain_can_write_kmsg 1
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87 If you want to allow all domains to use other domains file descriptors,
88 you must turn on the domain_fd_use boolean. Enabled by default.
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90 setsebool -P domain_fd_use 1
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94 If you want to allow all domains to have the kernel load modules, you
95 must turn on the domain_kernel_load_modules boolean. Disabled by
96 default.
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98 setsebool -P domain_kernel_load_modules 1
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102 If you want to allow all domains to execute in fips_mode, you must turn
103 on the fips_mode boolean. Enabled by default.
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105 setsebool -P fips_mode 1
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109 If you want to enable reading of urandom for all domains, you must turn
110 on the global_ssp boolean. Disabled by default.
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112 setsebool -P global_ssp 1
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117 The SELinux process type dmesg_t can manage files labeled with the fol‐
118 lowing file types. The paths listed are the default paths for these
119 file types. Note the processes UID still need to have DAC permissions.
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121 var_log_t
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123 /var/log/.*
124 /nsr/logs(/.*)?
125 /var/webmin(/.*)?
126 /var/log/secure[^/]*
127 /opt/zimbra/log(/.*)?
128 /var/log/maillog[^/]*
129 /var/log/spooler[^/]*
130 /var/log/messages[^/]*
131 /usr/centreon/log(/.*)?
132 /var/spool/rsyslog(/.*)?
133 /var/axfrdns/log/main(/.*)?
134 /var/spool/bacula/log(/.*)?
135 /var/tinydns/log/main(/.*)?
136 /var/dnscache/log/main(/.*)?
137 /var/stockmaniac/templates_cache(/.*)?
138 /opt/Symantec/scspagent/IDS/system(/.*)?
139 /var/log
140 /var/log/dmesg
141 /var/log/syslog
142 /var/named/chroot/var/log
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146 SELinux requires files to have an extended attribute to define the file
147 type.
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149 You can see the context of a file using the -Z option to ls
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151 Policy governs the access confined processes have to these files.
152 SELinux dmesg policy is very flexible allowing users to setup their
153 dmesg processes in as secure a method as possible.
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155 The following file types are defined for dmesg:
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159 dmesg_exec_t
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161 - Set files with the dmesg_exec_t type, if you want to transition an
162 executable to the dmesg_t domain.
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165 Paths:
166 /bin/dmesg, /usr/bin/dmesg
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169 Note: File context can be temporarily modified with the chcon command.
170 If you want to permanently change the file context you need to use the
171 semanage fcontext command. This will modify the SELinux labeling data‐
172 base. You will need to use restorecon to apply the labels.
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176 semanage fcontext can also be used to manipulate default file context
177 mappings.
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179 semanage permissive can also be used to manipulate whether or not a
180 process type is permissive.
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182 semanage module can also be used to enable/disable/install/remove pol‐
183 icy modules.
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185 semanage boolean can also be used to manipulate the booleans
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188 system-config-selinux is a GUI tool available to customize SELinux pol‐
189 icy settings.
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193 This manual page was auto-generated using sepolicy manpage .
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197 selinux(8), dmesg(8), semanage(8), restorecon(8), chcon(1), sepolicy(8)
198 , setsebool(8)
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202dmesg 19-04-25 dmesg_selinux(8)