1bootloader_selinux(8) SELinux Policy bootloader bootloader_selinux(8)
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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 file_type, unla‐
25 beled_t, proc_type, filesystem_type, mtrr_device_t, sysctl_type, boot‐
26 loader_exec_t file types.
27 The default entrypoint paths for the bootloader_t domain are the fol‐
29 lowing:
30 all files on the system, /dev/cpu/mtrr, /sbin/ybin.*, /sbin/lilo.*,
32 /sbin/zipl, /sbin/grub, /sbin/grubby, /usr/sbin/grub
33
35 SELinux defines process types (domains) for each process running on the
36 system
37 You can see the context of a process using the -Z option to ps
39 Policy governs the access confined processes have to files. SELinux
41 bootloader policy is very flexible allowing users to setup their boot‐
42 loader processes in as secure a method as possible.
43 The following process types are defined for bootloader:
45 bootloader_t
47 Note: semanage permissive -a bootloader_t can be used to make the
49 process type bootloader_t permissive. SELinux does not deny access to
50 permissive process types, but the AVC (SELinux denials) messages are
51 still generated.
52
55 SELinux policy is customizable based on least access required. boot‐
56 loader policy is extremely flexible and has several booleans that allow
57 you to manipulate the policy and run bootloader with the tightest
58 access possible.
59 If you want to allow all domains to use other domains file descriptors,
63 you must turn on the allow_domain_fd_use boolean. Enabled by default.
64 setsebool -P allow_domain_fd_use 1
66 If you want to allow unconfined executables to make their heap memory
70 executable. Doing this is a really bad idea. Probably indicates a
71 badly coded executable, but could indicate an attack. This executable
72 should be reported in bugzilla, you must turn on the allow_execheap
73 boolean. Disabled by default.
74 setsebool -P allow_execheap 1
76 If you want to allow unconfined executables to map a memory region as
80 both executable and writable, this is dangerous and the executable
81 should be reported in bugzilla), you must turn on the allow_execmem
82 boolean. Enabled by default.
83 setsebool -P allow_execmem 1
85 If you want to allow all unconfined executables to use libraries
89 requiring text relocation that are not labeled textrel_shlib_t), you
90 must turn on the allow_execmod boolean. Enabled by default.
91 setsebool -P allow_execmod 1
93 If you want to allow unconfined executables to make their stack exe‐
97 cutable. This should never, ever be necessary. Probably indicates a
98 badly coded executable, but could indicate an attack. This executable
99 should be reported in bugzilla), you must turn on the allow_execstack
100 boolean. Enabled by default.
101 setsebool -P allow_execstack 1
103 If you want to allow sysadm to debug or ptrace all processes, you must
107 turn on the allow_ptrace boolean. Disabled by default.
108 setsebool -P allow_ptrace 1
110 If you want to allow all domains to have the kernel load modules, you
114 must turn on the domain_kernel_load_modules boolean. Disabled by
115 default.
116 setsebool -P domain_kernel_load_modules 1
118 If you want to allow all domains to execute in fips_mode, you must turn
122 on the fips_mode boolean. Enabled by default.
123 setsebool -P fips_mode 1
125 If you want to enable reading of urandom for all domains, you must turn
129 on the global_ssp boolean. Disabled by default.
130 setsebool -P global_ssp 1
132 If you want to allow s-c-kdump to run bootloader in bootloader_t, you
136 must turn on the kdumpgui_run_bootloader boolean. Disabled by default.
137 setsebool -P kdumpgui_run_bootloader 1
139 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.
144 setsebool -P mmap_low_allowed 1
146 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.
153 setsebool -P secure_mode_policyload 1
155 If you want to support X userspace object manager, you must turn on the
159 xserver_object_manager boolean. Disabled by default.
160 setsebool -P xserver_object_manager 1
162
166 The SELinux process type bootloader_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.
169 file_type
171 all files on the system
173
176 SELinux requires files to have an extended attribute to define the file
177 type.
178 You can see the context of a file using the -Z option to ls
180 Policy governs the access confined processes have to these files.
182 SELinux bootloader policy is very flexible allowing users to setup
183 their bootloader processes in as secure a method as possible.
184 STANDARD FILE CONTEXT
186 SELinux defines the file context types for the bootloader, if you
188 wanted to store files with these types in a diffent paths, you need to
189 execute the semanage command to sepecify alternate labeling and then
190 use restorecon to put the labels on disk.
191 semanage fcontext -a -t bootloader_tmp_t '/srv/mybootloader_con‐
193 tent(/.*)?'
194 restorecon -R -v /srv/mybootloader_content
195 Note: SELinux often uses regular expressions to specify labels that
197 match multiple files.
198 The following file types are defined for bootloader:
200 bootloader_etc_t
204 - Set files with the bootloader_etc_t type, if you want to store boot‐
206 loader files in the /etc directories.
207 Paths:
210 /etc/lilo.conf.*, /etc/yaboot.conf.*, /boot/etc/yaboot.conf.*
211 bootloader_exec_t
214 - Set files with the bootloader_exec_t type, if you want to transition
216 an executable to the bootloader_t domain.
217 Paths:
220 /sbin/ybin.*, /sbin/lilo.*, /sbin/zipl, /sbin/grub, /sbin/grubby,
221 /usr/sbin/grub
222 bootloader_tmp_t
225 - Set files with the bootloader_tmp_t type, if you want to store boot‐
227 loader temporary files in the /tmp directories.
228 Note: File context can be temporarily modified with the chcon command.
232 If you want to permanently change the file context you need to use the
233 semanage fcontext command. This will modify the SELinux labeling data‐
234 base. You will need to use restorecon to apply the labels.
235
238 semanage fcontext can also be used to manipulate default file context
239 mappings.
240 semanage permissive can also be used to manipulate whether or not a
242 process type is permissive.
243 semanage module can also be used to enable/disable/install/remove pol‐
245 icy modules.
246 semanage boolean can also be used to manipulate the booleans
248 system-config-selinux is a GUI tool available to customize SELinux pol‐
251 icy settings.
252
255 This manual page was auto-generated using sepolicy manpage .
256
259 selinux(8), bootloader(8), semanage(8), restorecon(8), chcon(1) , set‐
260 sebool(8)
261bootloader 15-06-03 bootloader_selinux(8)