1udev_selinux(8) SELinux Policy udev udev_selinux(8)
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6 udev_selinux - Security Enhanced Linux Policy for the udev processes
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9 Security-Enhanced Linux secures the udev processes via flexible manda‐
10 tory access control.
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12 The udev processes execute with the udev_t SELinux type. You can check
13 if you have these processes running by executing the ps command with
14 the -Z qualifier.
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16 For example:
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18 ps -eZ | grep udev_t
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23 The udev_t SELinux type can be entered via the udev_exec_t,
24 udev_helper_exec_t file types.
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26 The default entrypoint paths for the udev_t domain are the following:
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28 /sbin/udev, /sbin/udevd, /bin/udevadm, /sbin/udevadm, /sbin/udevsend,
29 /usr/sbin/udev, /lib/udev/udevd, /sbin/udevstart, /usr/sbin/udevd,
30 /sbin/start_udev, /usr/bin/udevadm, /usr/bin/udevinfo, /usr/sbin/ude‐
31 vadm, /lib/udev/udev-acl, /usr/sbin/udevsend, /usr/lib/udev/udevd,
32 /usr/sbin/udevstart, /sbin/wait_for_sysfs, /usr/sbin/start_udev,
33 /usr/lib/udev/udev-acl, /usr/sbin/wait_for_sysfs, /usr/lib/systemd/sys‐
34 temd-udevd, /etc/dev.d/.+, /etc/udev/scripts/.+, /etc/hot‐
35 plug.d/default/udev.*
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38 SELinux defines process types (domains) for each process running on the
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41 You can see the context of a process using the -Z option to ps
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43 Policy governs the access confined processes have to files. SELinux
44 udev policy is very flexible allowing users to setup their udev pro‐
45 cesses in as secure a method as possible.
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47 The following process types are defined for udev:
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49 udev_t
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51 Note: semanage permissive -a udev_t can be used to make the process
52 type udev_t permissive. SELinux does not deny access to permissive
53 process types, but the AVC (SELinux denials) messages are still gener‐
54 ated.
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58 SELinux policy is customizable based on least access required. udev
59 policy is extremely flexible and has several booleans that allow you to
60 manipulate the policy and run udev with the tightest access possible.
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64 If you want to allow users to resolve user passwd entries directly from
65 ldap rather then using a sssd server, you must turn on the authlo‐
66 gin_nsswitch_use_ldap boolean. Disabled by default.
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68 setsebool -P authlogin_nsswitch_use_ldap 1
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72 If you want to deny user domains applications to map a memory region as
73 both executable and writable, this is dangerous and the executable
74 should be reported in bugzilla, you must turn on the deny_execmem bool‐
75 ean. Enabled by default.
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77 setsebool -P deny_execmem 1
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81 If you want to allow all domains to execute in fips_mode, you must turn
82 on the fips_mode boolean. Enabled by default.
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84 setsebool -P fips_mode 1
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88 If you want to allow confined applications to run with kerberos, you
89 must turn on the kerberos_enabled boolean. Enabled by default.
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91 setsebool -P kerberos_enabled 1
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95 If you want to control the ability to mmap a low area of the address
96 space, as configured by /proc/sys/vm/mmap_min_addr, you must turn on
97 the mmap_low_allowed boolean. Disabled by default.
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99 setsebool -P mmap_low_allowed 1
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103 If you want to allow system to run with NIS, you must turn on the
104 nis_enabled boolean. Disabled by default.
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106 setsebool -P nis_enabled 1
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110 If you want to allow confined applications to use nscd shared memory,
111 you must turn on the nscd_use_shm boolean. Disabled by default.
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113 setsebool -P nscd_use_shm 1
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117 If you want to disable kernel module loading, you must turn on the
118 secure_mode_insmod boolean. Enabled by default.
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120 setsebool -P secure_mode_insmod 1
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124 If you want to allow unconfined executables to make their heap memory
125 executable. Doing this is a really bad idea. Probably indicates a
126 badly coded executable, but could indicate an attack. This executable
127 should be reported in bugzilla, you must turn on the selin‐
128 uxuser_execheap boolean. Disabled by default.
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130 setsebool -P selinuxuser_execheap 1
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134 If you want to allow unconfined executables to make their stack exe‐
135 cutable. This should never, ever be necessary. Probably indicates a
136 badly coded executable, but could indicate an attack. This executable
137 should be reported in bugzilla, you must turn on the selinuxuser_exec‐
138 stack boolean. Enabled by default.
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140 setsebool -P selinuxuser_execstack 1
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145 The SELinux process type udev_t can manage files labeled with the fol‐
146 lowing file types. The paths listed are the default paths for these
147 file types. Note the processes UID still need to have DAC permissions.
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149 file_type
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151 all files on the system
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155 SELinux requires files to have an extended attribute to define the file
156 type.
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158 You can see the context of a file using the -Z option to ls
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160 Policy governs the access confined processes have to these files.
161 SELinux udev policy is very flexible allowing users to setup their udev
162 processes in as secure a method as possible.
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164 STANDARD FILE CONTEXT
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166 SELinux defines the file context types for the udev, if you wanted to
167 store files with these types in a diffent paths, you need to execute
168 the semanage command to sepecify alternate labeling and then use
169 restorecon to put the labels on disk.
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171 semanage fcontext -a -t udev_tmp_t '/srv/myudev_content(/.*)?'
172 restorecon -R -v /srv/myudev_content
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174 Note: SELinux often uses regular expressions to specify labels that
175 match multiple files.
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177 The following file types are defined for udev:
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181 udev_etc_t
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183 - Set files with the udev_etc_t type, if you want to store udev files
184 in the /etc directories.
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188 udev_exec_t
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190 - Set files with the udev_exec_t type, if you want to transition an
191 executable to the udev_t domain.
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194 Paths:
195 /sbin/udev, /sbin/udevd, /bin/udevadm, /sbin/udevadm, /sbin/ude‐
196 vsend, /usr/sbin/udev, /lib/udev/udevd, /sbin/udevstart,
197 /usr/sbin/udevd, /sbin/start_udev, /usr/bin/udevadm,
198 /usr/bin/udevinfo, /usr/sbin/udevadm, /lib/udev/udev-acl,
199 /usr/sbin/udevsend, /usr/lib/udev/udevd, /usr/sbin/udevstart,
200 /sbin/wait_for_sysfs, /usr/sbin/start_udev, /usr/lib/udev/udev-
201 acl, /usr/sbin/wait_for_sysfs, /usr/lib/systemd/systemd-udevd
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204 udev_helper_exec_t
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206 - Set files with the udev_helper_exec_t type, if you want to transition
207 an executable to the udev_helper_t domain.
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210 Paths:
211 /etc/dev.d/.+, /etc/udev/scripts/.+, /etc/hotplug.d/default/udev.*
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214 udev_rules_t
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216 - Set files with the udev_rules_t type, if you want to treat the files
217 as udev rules data.
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221 udev_tmp_t
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223 - Set files with the udev_tmp_t type, if you want to store udev tempo‐
224 rary files in the /tmp directories.
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228 udev_var_run_t
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230 - Set files with the udev_var_run_t type, if you want to store the udev
231 files under the /run or /var/run directory.
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234 Paths:
235 /dev/.udev(/.*)?, /var/run/udev(/.*)?, /var/run/libgpod(/.*)?,
236 /var/run/PackageKit/udev(/.*)?, /dev/.udevdb, /dev/udev.tbl
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239 Note: File context can be temporarily modified with the chcon command.
240 If you want to permanently change the file context you need to use the
241 semanage fcontext command. This will modify the SELinux labeling data‐
242 base. You will need to use restorecon to apply the labels.
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246 semanage fcontext can also be used to manipulate default file context
247 mappings.
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249 semanage permissive can also be used to manipulate whether or not a
250 process type is permissive.
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252 semanage module can also be used to enable/disable/install/remove pol‐
253 icy modules.
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255 semanage boolean can also be used to manipulate the booleans
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258 system-config-selinux is a GUI tool available to customize SELinux pol‐
259 icy settings.
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263 This manual page was auto-generated using sepolicy manpage .
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267 selinux(8), udev(8), semanage(8), restorecon(8), chcon(1), sepolicy(8),
268 setsebool(8)
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272udev 19-05-30 udev_selinux(8)