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 ac‐
57 cess possible.
58 If you want to control the ability to mmap a low area of the address
62 space, as configured by /proc/sys/vm/mmap_min_addr, you must turn on
63 the mmap_low_allowed boolean. Disabled by default.
64 setsebool -P mmap_low_allowed 1
66 If you want to allow system to run with NIS, you must turn on the
70 nis_enabled boolean. Disabled by default.
71 setsebool -P nis_enabled 1
73 If you want to disable kernel module loading, you must turn on the se‐
77 cure_mode_insmod boolean. Disabled by default.
78 setsebool -P secure_mode_insmod 1
80 If you want to allow unconfined executables to make their heap memory
84 executable. Doing this is a really bad idea. Probably indicates a
85 badly coded executable, but could indicate an attack. This executable
86 should be reported in bugzilla, you must turn on the selinuxuser_ex‐
87 echeap boolean. Disabled by default.
88 setsebool -P selinuxuser_execheap 1
90 If you want to allow unconfined executables to make their stack exe‐
94 cutable. This should never, ever be necessary. Probably indicates a
95 badly coded executable, but could indicate an attack. This executable
96 should be reported in bugzilla, you must turn on the selinuxuser_exec‐
97 stack boolean. Enabled by default.
98 setsebool -P selinuxuser_execstack 1
100
104 The SELinux process type bootloader_t can manage files labeled with the
105 following file types. The paths listed are the default paths for these
106 file types. Note the processes UID still need to have DAC permissions.
107 file_type
109 all files on the system
111
114 SELinux requires files to have an extended attribute to define the file
115 type.
116 You can see the context of a file using the -Z option to ls
118 Policy governs the access confined processes have to these files.
120 SELinux bootloader policy is very flexible allowing users to setup
121 their bootloader processes in as secure a method as possible.
122 STANDARD FILE CONTEXT
124 SELinux defines the file context types for the bootloader, if you
126 wanted to store files with these types in a different paths, you need
127 to execute the semanage command to specify alternate labeling and then
128 use restorecon to put the labels on disk.
129 semanage fcontext -a -t bootloader_exec_t '/srv/bootloader/con‐
131 tent(/.*)?'
132 restorecon -R -v /srv/mybootloader_content
133 Note: SELinux often uses regular expressions to specify labels that
135 match multiple files.
136 The following file types are defined for bootloader:
138 bootloader_etc_t
142 - Set files with the bootloader_etc_t type, if you want to store boot‐
144 loader files in the /etc directories.
145 Paths:
148 /etc/lilo.conf.*, /etc/zipl.conf.*, /etc/yaboot.conf.*, /etc/de‐
149 fault/grub
150 bootloader_exec_t
153 - Set files with the bootloader_exec_t type, if you want to transition
155 an executable to the bootloader_t domain.
156 Paths:
159 /sbin/grub.*, /sbin/lilo.*, /sbin/ybin.*, /usr/sbin/grub.*,
160 /usr/sbin/lilo.*, /usr/sbin/ybin.*, /sbin/zipl, /usr/sbin/zipl
161 bootloader_tmp_t
164 - Set files with the bootloader_tmp_t type, if you want to store boot‐
166 loader temporary files in the /tmp directories.
167 bootloader_var_lib_t
171 - Set files with the bootloader_var_lib_t type, if you want to store
173 the bootloader files under the /var/lib directory.
174 bootloader_var_run_t
178 - Set files with the bootloader_var_run_t type, if you want to store
180 the bootloader files under the /run or /var/run directory.
181 Note: File context can be temporarily modified with the chcon command.
185 If you want to permanently change the file context you need to use the
186 semanage fcontext command. This will modify the SELinux labeling data‐
187 base. You will need to use restorecon to apply the labels.
188
191 semanage fcontext can also be used to manipulate default file context
192 mappings.
193 semanage permissive can also be used to manipulate whether or not a
195 process type is permissive.
196 semanage module can also be used to enable/disable/install/remove pol‐
198 icy modules.
199 semanage boolean can also be used to manipulate the booleans
201 system-config-selinux is a GUI tool available to customize SELinux pol‐
204 icy settings.
205
208 This manual page was auto-generated using sepolicy manpage .
209
212 selinux(8), bootloader(8), semanage(8), restorecon(8), chcon(1), sepol‐
213 icy(8), setsebool(8)
214bootloader 23-12-15 bootloader_selinux(8)