1bootloader_selinux(8) SELinux Policy bootloader bootloader_selinux(8)
2
6 bootloader_selinux - Security Enhanced Linux Policy for the bootloader
7 processes
8
10 Security-Enhanced Linux secures the bootloader processes via flexible
11 mandatory access control.
12 The bootloader processes execute with the bootloader_t SELinux type.
14 You can check if you have these processes running by executing the ps
15 command with the -Z qualifier.
16 For example:
18 ps -eZ | grep bootloader_t
20
24 The bootloader_t SELinux type can be entered via the bootloader_exec_t
25 file type.
26 The default entrypoint paths for the bootloader_t domain are the fol‐
28 lowing:
29 /sbin/grub.*, /sbin/lilo.*, /sbin/ybin.*, /usr/sbin/grub.*,
31 /usr/sbin/lilo.*, /usr/sbin/ybin.*, /sbin/zipl, /usr/sbin/zipl
32
34 SELinux defines process types (domains) for each process running on the
35 system
36 You can see the context of a process using the -Z option to ps
38 Policy governs the access confined processes have to files. SELinux
40 bootloader policy is very flexible allowing users to setup their boot‐
41 loader processes in as secure a method as possible.
42 The following process types are defined for bootloader:
44 bootloader_t
46 Note: semanage permissive -a bootloader_t can be used to make the
48 process type bootloader_t permissive. SELinux does not deny access to
49 permissive process types, but the AVC (SELinux denials) messages are
50 still generated.
51
54 SELinux policy is customizable based on least access required. boot‐
55 loader policy is extremely flexible and has several booleans that allow
56 you to manipulate the policy and run bootloader with the tightest
57 access possible.
58 If you want to allow users to resolve user passwd entries directly from
62 ldap rather then using a sssd server, you must turn on the authlo‐
63 gin_nsswitch_use_ldap boolean. Disabled by default.
64 setsebool -P authlogin_nsswitch_use_ldap 1
66 If you want to deny user domains applications to map a memory region as
70 both executable and writable, this is dangerous and the executable
71 should be reported in bugzilla, you must turn on the deny_execmem bool‐
72 ean. Enabled by default.
73 setsebool -P deny_execmem 1
75 If you want to allow all domains to execute in fips_mode, you must turn
79 on the fips_mode boolean. Enabled by default.
80 setsebool -P fips_mode 1
82 If you want to allow s-c-kdump to run bootloader in bootloader_t, you
86 must turn on the kdumpgui_run_bootloader boolean. Disabled by default.
87 setsebool -P kdumpgui_run_bootloader 1
89 If you want to allow confined applications to run with kerberos, you
93 must turn on the kerberos_enabled boolean. Disabled by default.
94 setsebool -P kerberos_enabled 1
96 If you want to control the ability to mmap a low area of the address
100 space, as configured by /proc/sys/vm/mmap_min_addr, you must turn on
101 the mmap_low_allowed boolean. Disabled by default.
102 setsebool -P mmap_low_allowed 1
104 If you want to allow system to run with NIS, you must turn on the
108 nis_enabled boolean. Disabled by default.
109 setsebool -P nis_enabled 1
111 If you want to allow confined applications to use nscd shared memory,
115 you must turn on the nscd_use_shm boolean. Disabled by default.
116 setsebool -P nscd_use_shm 1
118 If you want to disable kernel module loading, you must turn on the
122 secure_mode_insmod boolean. Enabled by default.
123 setsebool -P secure_mode_insmod 1
125 If you want to allow unconfined executables to make their heap memory
129 executable. Doing this is a really bad idea. Probably indicates a
130 badly coded executable, but could indicate an attack. This executable
131 should be reported in bugzilla, you must turn on the selin‐
132 uxuser_execheap boolean. Disabled by default.
133 setsebool -P selinuxuser_execheap 1
135 If you want to allow unconfined executables to make their stack exe‐
139 cutable. This should never, ever be necessary. 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 selinuxuser_exec‐
142 stack boolean. Disabled by default.
143 setsebool -P selinuxuser_execstack 1
145
149 The SELinux process type bootloader_t can manage files labeled with the
150 following file types. The paths listed are the default paths for these
151 file types. Note the processes UID still need to have DAC permissions.
152 file_type
154 all files on the system
156
159 SELinux requires files to have an extended attribute to define the file
160 type.
161 You can see the context of a file using the -Z option to ls
163 Policy governs the access confined processes have to these files.
165 SELinux bootloader policy is very flexible allowing users to setup
166 their bootloader processes in as secure a method as possible.
167 STANDARD FILE CONTEXT
169 SELinux defines the file context types for the bootloader, if you
171 wanted to store files with these types in a diffent paths, you need to
172 execute the semanage command to sepecify alternate labeling and then
173 use restorecon to put the labels on disk.
174 semanage fcontext -a -t bootloader_tmp_t '/srv/mybootloader_con‐
176 tent(/.*)?'
177 restorecon -R -v /srv/mybootloader_content
178 Note: SELinux often uses regular expressions to specify labels that
180 match multiple files.
181 The following file types are defined for bootloader:
183 bootloader_etc_t
187 - Set files with the bootloader_etc_t type, if you want to store boot‐
189 loader files in the /etc directories.
190 Paths:
193 /etc/lilo.conf.*, /etc/zipl.conf.*, /etc/yaboot.conf.*,
194 /etc/default/grub
195 bootloader_exec_t
198 - Set files with the bootloader_exec_t type, if you want to transition
200 an executable to the bootloader_t domain.
201 Paths:
204 /sbin/grub.*, /sbin/lilo.*, /sbin/ybin.*, /usr/sbin/grub.*,
205 /usr/sbin/lilo.*, /usr/sbin/ybin.*, /sbin/zipl, /usr/sbin/zipl
206 bootloader_tmp_t
209 - Set files with the bootloader_tmp_t type, if you want to store boot‐
211 loader temporary files in the /tmp directories.
212 bootloader_var_lib_t
216 - Set files with the bootloader_var_lib_t type, if you want to store
218 the bootloader files under the /var/lib directory.
219 bootloader_var_run_t
223 - Set files with the bootloader_var_run_t type, if you want to store
225 the bootloader files under the /run or /var/run directory.
226 Note: File context can be temporarily modified with the chcon command.
230 If you want to permanently change the file context you need to use the
231 semanage fcontext command. This will modify the SELinux labeling data‐
232 base. You will need to use restorecon to apply the labels.
233
236 semanage fcontext can also be used to manipulate default file context
237 mappings.
238 semanage permissive can also be used to manipulate whether or not a
240 process type is permissive.
241 semanage module can also be used to enable/disable/install/remove pol‐
243 icy modules.
244 semanage boolean can also be used to manipulate the booleans
246 system-config-selinux is a GUI tool available to customize SELinux pol‐
249 icy settings.
250
253 This manual page was auto-generated using sepolicy manpage .
254
257 selinux(8), bootloader(8), semanage(8), restorecon(8), chcon(1), sepol‐
258 icy(8), setsebool(8)
259bootloader 19-12-02 bootloader_selinux(8)