1 # SPDX-License-Identifier: GPL-2.0-only <<
2 # 1 #
3 # Security configuration 2 # Security configuration
4 # 3 #
5 4
6 menu "Security options" 5 menu "Security options"
7 6
8 source "security/keys/Kconfig" !! 7 source security/keys/Kconfig
9 8
10 config SECURITY_DMESG_RESTRICT 9 config SECURITY_DMESG_RESTRICT
11 bool "Restrict unprivileged access to 10 bool "Restrict unprivileged access to the kernel syslog"
12 default n 11 default n
13 help 12 help
14 This enforces restrictions on unpriv 13 This enforces restrictions on unprivileged users reading the kernel
15 syslog via dmesg(8). 14 syslog via dmesg(8).
16 15
17 If this option is not selected, no r 16 If this option is not selected, no restrictions will be enforced
18 unless the dmesg_restrict sysctl is 17 unless the dmesg_restrict sysctl is explicitly set to (1).
19 18
20 If you are unsure how to answer this 19 If you are unsure how to answer this question, answer N.
21 20
22 choice <<
23 prompt "Allow /proc/pid/mem access ove <<
24 default PROC_MEM_ALWAYS_FORCE <<
25 help <<
26 Traditionally /proc/pid/mem allows u <<
27 permissions for users like ptrace, a <<
28 capability. <<
29 <<
30 This allows people to limit that - e <<
31 require actual active ptrace attachm <<
32 <<
33 Defaults to the traditional behavior <<
34 <<
35 config PROC_MEM_ALWAYS_FORCE <<
36 bool "Traditional /proc/pid/mem behavi <<
37 help <<
38 This allows /proc/pid/mem accesses t <<
39 permissions if you have ptrace acces <<
40 <<
41 config PROC_MEM_FORCE_PTRACE <<
42 bool "Require active ptrace() use for <<
43 help <<
44 This allows /proc/pid/mem accesses t <<
45 permissions for active ptracers like <<
46 <<
47 config PROC_MEM_NO_FORCE <<
48 bool "Never" <<
49 help <<
50 Never override memory mapping permis <<
51 <<
52 endchoice <<
53 <<
54 config SECURITY 21 config SECURITY
55 bool "Enable different security models 22 bool "Enable different security models"
56 depends on SYSFS 23 depends on SYSFS
57 depends on MULTIUSER 24 depends on MULTIUSER
58 help 25 help
59 This allows you to choose different 26 This allows you to choose different security modules to be
60 configured into your kernel. 27 configured into your kernel.
61 28
62 If this option is not selected, the 29 If this option is not selected, the default Linux security
63 model will be used. 30 model will be used.
64 31
65 If you are unsure how to answer this 32 If you are unsure how to answer this question, answer N.
66 33
67 config SECURITYFS 34 config SECURITYFS
68 bool "Enable the securityfs filesystem 35 bool "Enable the securityfs filesystem"
69 help 36 help
70 This will build the securityfs files 37 This will build the securityfs filesystem. It is currently used by
71 various security modules (AppArmor, !! 38 the TPM bios character driver and IMA, an integrity provider. It is
>> 39 not used by SELinux or SMACK.
72 40
73 If you are unsure how to answer this 41 If you are unsure how to answer this question, answer N.
74 42
75 config SECURITY_NETWORK 43 config SECURITY_NETWORK
76 bool "Socket and Networking Security H 44 bool "Socket and Networking Security Hooks"
77 depends on SECURITY 45 depends on SECURITY
78 help 46 help
79 This enables the socket and networki 47 This enables the socket and networking security hooks.
80 If enabled, a security module can us 48 If enabled, a security module can use these hooks to
81 implement socket and networking acce 49 implement socket and networking access controls.
82 If you are unsure how to answer this 50 If you are unsure how to answer this question, answer N.
83 51
84 config SECURITY_INFINIBAND <<
85 bool "Infiniband Security Hooks" <<
86 depends on SECURITY && INFINIBAND <<
87 help <<
88 This enables the Infiniband security <<
89 If enabled, a security module can us <<
90 implement Infiniband access controls <<
91 If you are unsure how to answer this <<
92 <<
93 config SECURITY_NETWORK_XFRM 52 config SECURITY_NETWORK_XFRM
94 bool "XFRM (IPSec) Networking Security 53 bool "XFRM (IPSec) Networking Security Hooks"
95 depends on XFRM && SECURITY_NETWORK 54 depends on XFRM && SECURITY_NETWORK
96 help 55 help
97 This enables the XFRM (IPSec) networ 56 This enables the XFRM (IPSec) networking security hooks.
98 If enabled, a security module can us 57 If enabled, a security module can use these hooks to
99 implement per-packet access controls 58 implement per-packet access controls based on labels
100 derived from IPSec policy. Non-IPSe 59 derived from IPSec policy. Non-IPSec communications are
101 designated as unlabelled, and only s 60 designated as unlabelled, and only sockets authorized
102 to communicate unlabelled data can s 61 to communicate unlabelled data can send without using
103 IPSec. 62 IPSec.
104 If you are unsure how to answer this 63 If you are unsure how to answer this question, answer N.
105 64
106 config SECURITY_PATH 65 config SECURITY_PATH
107 bool "Security hooks for pathname base 66 bool "Security hooks for pathname based access control"
108 depends on SECURITY 67 depends on SECURITY
109 help 68 help
110 This enables the security hooks for 69 This enables the security hooks for pathname based access control.
111 If enabled, a security module can us 70 If enabled, a security module can use these hooks to
112 implement pathname based access cont 71 implement pathname based access controls.
113 If you are unsure how to answer this 72 If you are unsure how to answer this question, answer N.
114 73
115 config INTEL_TXT 74 config INTEL_TXT
116 bool "Enable Intel(R) Trusted Executio 75 bool "Enable Intel(R) Trusted Execution Technology (Intel(R) TXT)"
117 depends on HAVE_INTEL_TXT 76 depends on HAVE_INTEL_TXT
118 help 77 help
119 This option enables support for boot 78 This option enables support for booting the kernel with the
120 Trusted Boot (tboot) module. This wi 79 Trusted Boot (tboot) module. This will utilize
121 Intel(R) Trusted Execution Technolog 80 Intel(R) Trusted Execution Technology to perform a measured launch
122 of the kernel. If the system does no 81 of the kernel. If the system does not support Intel(R) TXT, this
123 will have no effect. 82 will have no effect.
124 83
125 Intel TXT will provide higher assura 84 Intel TXT will provide higher assurance of system configuration and
126 initial state as well as data reset 85 initial state as well as data reset protection. This is used to
127 create a robust initial kernel measu 86 create a robust initial kernel measurement and verification, which
128 helps to ensure that kernel security 87 helps to ensure that kernel security mechanisms are functioning
129 correctly. This level of protection 88 correctly. This level of protection requires a root of trust outside
130 of the kernel itself. 89 of the kernel itself.
131 90
132 Intel TXT also helps solve real end 91 Intel TXT also helps solve real end user concerns about having
133 confidence that their hardware is ru 92 confidence that their hardware is running the VMM or kernel that
134 it was configured with, especially s 93 it was configured with, especially since they may be responsible for
135 providing such assurances to VMs and 94 providing such assurances to VMs and services running on it.
136 95
137 See <https://www.intel.com/technolog !! 96 See <http://www.intel.com/technology/security/> for more information
138 about Intel(R) TXT. 97 about Intel(R) TXT.
139 See <http://tboot.sourceforge.net> f 98 See <http://tboot.sourceforge.net> for more information about tboot.
140 See Documentation/arch/x86/intel_txt !! 99 See Documentation/intel_txt.txt for a description of how to enable
141 Intel TXT support in a kernel boot. 100 Intel TXT support in a kernel boot.
142 101
143 If you are unsure as to whether this 102 If you are unsure as to whether this is required, answer N.
144 103
145 config LSM_MMAP_MIN_ADDR 104 config LSM_MMAP_MIN_ADDR
146 int "Low address space for LSM to prot 105 int "Low address space for LSM to protect from user allocation"
147 depends on SECURITY && SECURITY_SELINU 106 depends on SECURITY && SECURITY_SELINUX
148 default 32768 if ARM || (ARM64 && COMP 107 default 32768 if ARM || (ARM64 && COMPAT)
149 default 65536 108 default 65536
150 help 109 help
151 This is the portion of low virtual m 110 This is the portion of low virtual memory which should be protected
152 from userspace allocation. Keeping 111 from userspace allocation. Keeping a user from writing to low pages
153 can help reduce the impact of kernel 112 can help reduce the impact of kernel NULL pointer bugs.
154 113
155 For most ia64, ppc64 and x86 users w 114 For most ia64, ppc64 and x86 users with lots of address space
156 a value of 65536 is reasonable and s 115 a value of 65536 is reasonable and should cause no problems.
157 On arm and other archs it should not 116 On arm and other archs it should not be higher than 32768.
158 Programs which use vm86 functionalit 117 Programs which use vm86 functionality or have some need to map
159 this low address space will need the 118 this low address space will need the permission specific to the
160 systems running LSM. 119 systems running LSM.
161 120
>> 121 config HAVE_HARDENED_USERCOPY_ALLOCATOR
>> 122 bool
>> 123 help
>> 124 The heap allocator implements __check_heap_object() for
>> 125 validating memory ranges against heap object sizes in
>> 126 support of CONFIG_HARDENED_USERCOPY.
>> 127
>> 128 config HAVE_ARCH_HARDENED_USERCOPY
>> 129 bool
>> 130 help
>> 131 The architecture supports CONFIG_HARDENED_USERCOPY by
>> 132 calling check_object_size() just before performing the
>> 133 userspace copies in the low level implementation of
>> 134 copy_to_user() and copy_from_user().
>> 135
162 config HARDENED_USERCOPY 136 config HARDENED_USERCOPY
163 bool "Harden memory copies between ker 137 bool "Harden memory copies between kernel and userspace"
164 imply STRICT_DEVMEM !! 138 depends on HAVE_ARCH_HARDENED_USERCOPY
>> 139 depends on HAVE_HARDENED_USERCOPY_ALLOCATOR
>> 140 select BUG
165 help 141 help
166 This option checks for obviously wro 142 This option checks for obviously wrong memory regions when
167 copying memory to/from the kernel (v 143 copying memory to/from the kernel (via copy_to_user() and
168 copy_from_user() functions) by rejec 144 copy_from_user() functions) by rejecting memory ranges that
169 are larger than the specified heap o 145 are larger than the specified heap object, span multiple
170 separately allocated pages, are not !! 146 separately allocates pages, are not on the process stack,
171 or are part of the kernel text. This !! 147 or are part of the kernel text. This kills entire classes
172 of heap overflow exploits and simila 148 of heap overflow exploits and similar kernel memory exposures.
173 149
174 config FORTIFY_SOURCE !! 150 config HARDENED_USERCOPY_PAGESPAN
175 bool "Harden common str/mem functions !! 151 bool "Refuse to copy allocations that span multiple pages"
176 depends on ARCH_HAS_FORTIFY_SOURCE !! 152 depends on HARDENED_USERCOPY
177 # https://github.com/llvm/llvm-project !! 153 depends on EXPERT
178 depends on !CC_IS_CLANG || !X86_32 !! 154 help
179 help !! 155 When a multi-page allocation is done without __GFP_COMP,
180 Detect overflows of buffers in commo !! 156 hardened usercopy will reject attempts to copy it. There are,
181 where the compiler can determine and !! 157 however, several cases of this in the kernel that have not all
182 !! 158 been removed. This config is intended to be used only while
183 config STATIC_USERMODEHELPER !! 159 trying to find such users.
184 bool "Force all usermode helper calls !! 160
185 help !! 161 source security/selinux/Kconfig
186 By default, the kernel can call many !! 162 source security/smack/Kconfig
187 binary programs through the "usermod !! 163 source security/tomoyo/Kconfig
188 interface. Some of these binaries a !! 164 source security/apparmor/Kconfig
189 either in the kernel code itself, or !! 165 source security/loadpin/Kconfig
190 option. However, some of these are !! 166 source security/yama/Kconfig
191 runtime, or can be modified after th <<
192 To provide an additional layer of se <<
193 calls through a single executable th <<
194 changed. <<
195 <<
196 Note, it is up to this single binary <<
197 "real" usermode helper binary, based <<
198 passed to it. If desired, this prog <<
199 and choose what real programs are ca <<
200 <<
201 If you wish for all usermode helper <<
202 disabled, choose this option and the <<
203 STATIC_USERMODEHELPER_PATH to an emp <<
204 <<
205 config STATIC_USERMODEHELPER_PATH <<
206 string "Path to the static usermode he <<
207 depends on STATIC_USERMODEHELPER <<
208 default "/sbin/usermode-helper" <<
209 help <<
210 The binary called by the kernel when <<
211 program is wish to be run. The "rea <<
212 be in the first argument passed to t <<
213 line. <<
214 <<
215 If you wish for all usermode helper <<
216 specify an empty string here (i.e. " <<
217 <<
218 source "security/selinux/Kconfig" <<
219 source "security/smack/Kconfig" <<
220 source "security/tomoyo/Kconfig" <<
221 source "security/apparmor/Kconfig" <<
222 source "security/loadpin/Kconfig" <<
223 source "security/yama/Kconfig" <<
224 source "security/safesetid/Kconfig" <<
225 source "security/lockdown/Kconfig" <<
226 source "security/landlock/Kconfig" <<
227 source "security/ipe/Kconfig" <<
228 167
229 source "security/integrity/Kconfig" !! 168 source security/integrity/Kconfig
230 169
231 choice 170 choice
232 prompt "First legacy 'major LSM' to be !! 171 prompt "Default security module"
233 default DEFAULT_SECURITY_SELINUX if SE 172 default DEFAULT_SECURITY_SELINUX if SECURITY_SELINUX
234 default DEFAULT_SECURITY_SMACK if SECU 173 default DEFAULT_SECURITY_SMACK if SECURITY_SMACK
235 default DEFAULT_SECURITY_TOMOYO if SEC 174 default DEFAULT_SECURITY_TOMOYO if SECURITY_TOMOYO
236 default DEFAULT_SECURITY_APPARMOR if S 175 default DEFAULT_SECURITY_APPARMOR if SECURITY_APPARMOR
237 default DEFAULT_SECURITY_DAC 176 default DEFAULT_SECURITY_DAC
238 177
239 help 178 help
240 This choice is there only for conver !! 179 Select the security module that will be used by default if the
241 in old kernel configs to CONFIG_LSM !! 180 kernel parameter security= is not specified.
242 change this choice unless you are cr <<
243 for this choice will be ignored afte <<
244 <<
245 Selects the legacy "major security m <<
246 initialized first. Overridden by non <<
247 181
248 config DEFAULT_SECURITY_SELINUX 182 config DEFAULT_SECURITY_SELINUX
249 bool "SELinux" if SECURITY_SEL 183 bool "SELinux" if SECURITY_SELINUX=y
250 184
251 config DEFAULT_SECURITY_SMACK 185 config DEFAULT_SECURITY_SMACK
252 bool "Simplified Mandatory Acc 186 bool "Simplified Mandatory Access Control" if SECURITY_SMACK=y
253 187
254 config DEFAULT_SECURITY_TOMOYO 188 config DEFAULT_SECURITY_TOMOYO
255 bool "TOMOYO" if SECURITY_TOMO 189 bool "TOMOYO" if SECURITY_TOMOYO=y
256 190
257 config DEFAULT_SECURITY_APPARMOR 191 config DEFAULT_SECURITY_APPARMOR
258 bool "AppArmor" if SECURITY_AP 192 bool "AppArmor" if SECURITY_APPARMOR=y
259 193
260 config DEFAULT_SECURITY_DAC 194 config DEFAULT_SECURITY_DAC
261 bool "Unix Discretionary Acces 195 bool "Unix Discretionary Access Controls"
262 196
263 endchoice 197 endchoice
264 198
265 config LSM !! 199 config DEFAULT_SECURITY
266 string "Ordered list of enabled LSMs" !! 200 string
267 default "landlock,lockdown,yama,loadpi !! 201 default "selinux" if DEFAULT_SECURITY_SELINUX
268 default "landlock,lockdown,yama,loadpi !! 202 default "smack" if DEFAULT_SECURITY_SMACK
269 default "landlock,lockdown,yama,loadpi !! 203 default "tomoyo" if DEFAULT_SECURITY_TOMOYO
270 default "landlock,lockdown,yama,loadpi !! 204 default "apparmor" if DEFAULT_SECURITY_APPARMOR
271 default "landlock,lockdown,yama,loadpi !! 205 default "" if DEFAULT_SECURITY_DAC
272 help <<
273 A comma-separated list of LSMs, in i <<
274 Any LSMs left off this list, except <<
275 LSM_ORDER_FIRST and LSM_ORDER_LAST, <<
276 if selected in the kernel configurat <<
277 This can be controlled at boot with <<
278 <<
279 If unsure, leave this as the default <<
280 <<
281 source "security/Kconfig.hardening" <<
282 206
283 source "security/ccsecurity/Kconfig" !! 207 source security/ccsecurity/Kconfig
284 208
285 endmenu 209 endmenu
286 210
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