2 # Security configuration
5 menu "Security options"
7 source security/keys/Kconfig
9 config SECURITY_DMESG_RESTRICT
10 bool "Restrict unprivileged access to the kernel syslog"
13 This enforces restrictions on unprivileged users reading the kernel
16 If this option is not selected, no restrictions will be enforced
17 unless the dmesg_restrict sysctl is explicitly set to (1).
19 If you are unsure how to answer this question, answer N.
22 bool "Enable different security models"
26 This allows you to choose different security modules to be
27 configured into your kernel.
29 If this option is not selected, the default Linux security
32 If you are unsure how to answer this question, answer N.
35 bool "Enable the securityfs filesystem"
37 This will build the securityfs filesystem. It is currently used by
38 the TPM bios character driver and IMA, an integrity provider. It is
39 not used by SELinux or SMACK.
41 If you are unsure how to answer this question, answer N.
43 config SECURITY_NETWORK
44 bool "Socket and Networking Security Hooks"
47 This enables the socket and networking security hooks.
48 If enabled, a security module can use these hooks to
49 implement socket and networking access controls.
50 If you are unsure how to answer this question, answer N.
52 config SECURITY_NETWORK_XFRM
53 bool "XFRM (IPSec) Networking Security Hooks"
54 depends on XFRM && SECURITY_NETWORK
56 This enables the XFRM (IPSec) networking security hooks.
57 If enabled, a security module can use these hooks to
58 implement per-packet access controls based on labels
59 derived from IPSec policy. Non-IPSec communications are
60 designated as unlabelled, and only sockets authorized
61 to communicate unlabelled data can send without using
63 If you are unsure how to answer this question, answer N.
66 bool "Security hooks for pathname based access control"
69 This enables the security hooks for pathname based access control.
70 If enabled, a security module can use these hooks to
71 implement pathname based access controls.
72 If you are unsure how to answer this question, answer N.
75 bool "Enable Intel(R) Trusted Execution Technology (Intel(R) TXT)"
76 depends on HAVE_INTEL_TXT
78 This option enables support for booting the kernel with the
79 Trusted Boot (tboot) module. This will utilize
80 Intel(R) Trusted Execution Technology to perform a measured launch
81 of the kernel. If the system does not support Intel(R) TXT, this
84 Intel TXT will provide higher assurance of system configuration and
85 initial state as well as data reset protection. This is used to
86 create a robust initial kernel measurement and verification, which
87 helps to ensure that kernel security mechanisms are functioning
88 correctly. This level of protection requires a root of trust outside
91 Intel TXT also helps solve real end user concerns about having
92 confidence that their hardware is running the VMM or kernel that
93 it was configured with, especially since they may be responsible for
94 providing such assurances to VMs and services running on it.
96 See <http://www.intel.com/technology/security/> for more information
98 See <http://tboot.sourceforge.net> for more information about tboot.
99 See Documentation/intel_txt.txt for a description of how to enable
100 Intel TXT support in a kernel boot.
102 If you are unsure as to whether this is required, answer N.
104 config LSM_MMAP_MIN_ADDR
105 int "Low address space for LSM to protect from user allocation"
106 depends on SECURITY && SECURITY_SELINUX
107 default 32768 if ARM || (ARM64 && COMPAT)
110 This is the portion of low virtual memory which should be protected
111 from userspace allocation. Keeping a user from writing to low pages
112 can help reduce the impact of kernel NULL pointer bugs.
114 For most ia64, ppc64 and x86 users with lots of address space
115 a value of 65536 is reasonable and should cause no problems.
116 On arm and other archs it should not be higher than 32768.
117 Programs which use vm86 functionality or have some need to map
118 this low address space will need the permission specific to the
121 config HAVE_HARDENED_USERCOPY_ALLOCATOR
124 The heap allocator implements __check_heap_object() for
125 validating memory ranges against heap object sizes in
126 support of CONFIG_HARDENED_USERCOPY.
128 config HARDENED_USERCOPY
129 bool "Harden memory copies between kernel and userspace"
130 depends on HAVE_HARDENED_USERCOPY_ALLOCATOR
133 This option checks for obviously wrong memory regions when
134 copying memory to/from the kernel (via copy_to_user() and
135 copy_from_user() functions) by rejecting memory ranges that
136 are larger than the specified heap object, span multiple
137 separately allocates pages, are not on the process stack,
138 or are part of the kernel text. This kills entire classes
139 of heap overflow exploits and similar kernel memory exposures.
141 config HARDENED_USERCOPY_PAGESPAN
142 bool "Refuse to copy allocations that span multiple pages"
143 depends on HARDENED_USERCOPY
146 When a multi-page allocation is done without __GFP_COMP,
147 hardened usercopy will reject attempts to copy it. There are,
148 however, several cases of this in the kernel that have not all
149 been removed. This config is intended to be used only while
150 trying to find such users.
152 config STATIC_USERMODEHELPER
153 bool "Force all usermode helper calls through a single binary"
155 By default, the kernel can call many different userspace
156 binary programs through the "usermode helper" kernel
157 interface. Some of these binaries are statically defined
158 either in the kernel code itself, or as a kernel configuration
159 option. However, some of these are dynamically created at
160 runtime, or can be modified after the kernel has started up.
161 To provide an additional layer of security, route all of these
162 calls through a single executable that can not have its name
165 Note, it is up to this single binary to then call the relevant
166 "real" usermode helper binary, based on the first argument
167 passed to it. If desired, this program can filter and pick
168 and choose what real programs are called.
170 If you wish for all usermode helper programs are to be
171 disabled, choose this option and then set
172 STATIC_USERMODEHELPER_PATH to an empty string.
174 config STATIC_USERMODEHELPER_PATH
175 string "Path to the static usermode helper binary"
176 depends on STATIC_USERMODEHELPER
177 default "/sbin/usermode-helper"
179 The binary called by the kernel when any usermode helper
180 program is wish to be run. The "real" application's name will
181 be in the first argument passed to this program on the command
184 If you wish for all usermode helper programs to be disabled,
185 specify an empty string here (i.e. "").
187 source security/selinux/Kconfig
188 source security/smack/Kconfig
189 source security/tomoyo/Kconfig
190 source security/apparmor/Kconfig
191 source security/loadpin/Kconfig
192 source security/yama/Kconfig
194 source security/integrity/Kconfig
197 prompt "Default security module"
198 default DEFAULT_SECURITY_SELINUX if SECURITY_SELINUX
199 default DEFAULT_SECURITY_SMACK if SECURITY_SMACK
200 default DEFAULT_SECURITY_TOMOYO if SECURITY_TOMOYO
201 default DEFAULT_SECURITY_APPARMOR if SECURITY_APPARMOR
202 default DEFAULT_SECURITY_DAC
205 Select the security module that will be used by default if the
206 kernel parameter security= is not specified.
208 config DEFAULT_SECURITY_SELINUX
209 bool "SELinux" if SECURITY_SELINUX=y
211 config DEFAULT_SECURITY_SMACK
212 bool "Simplified Mandatory Access Control" if SECURITY_SMACK=y
214 config DEFAULT_SECURITY_TOMOYO
215 bool "TOMOYO" if SECURITY_TOMOYO=y
217 config DEFAULT_SECURITY_APPARMOR
218 bool "AppArmor" if SECURITY_APPARMOR=y
220 config DEFAULT_SECURITY_DAC
221 bool "Unix Discretionary Access Controls"
225 config DEFAULT_SECURITY
227 default "selinux" if DEFAULT_SECURITY_SELINUX
228 default "smack" if DEFAULT_SECURITY_SMACK
229 default "tomoyo" if DEFAULT_SECURITY_TOMOYO
230 default "apparmor" if DEFAULT_SECURITY_APPARMOR
231 default "" if DEFAULT_SECURITY_DAC