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
>> 34 config PAGE_TABLE_ISOLATION
>> 35 bool "Remove the kernel mapping in user mode"
>> 36 default y
>> 37 depends on X86_64 && SMP
>> 38 help
>> 39 This enforces a strict kernel and user space isolation, in order
>> 40 to close hardware side channels on kernel address information.
>> 41
>> 42 If you are unsure how to answer this question, answer Y.
>> 43
67 config SECURITYFS 44 config SECURITYFS
68 bool "Enable the securityfs filesystem 45 bool "Enable the securityfs filesystem"
69 help 46 help
70 This will build the securityfs files 47 This will build the securityfs filesystem. It is currently used by
71 various security modules (AppArmor, !! 48 the TPM bios character driver and IMA, an integrity provider. It is
>> 49 not used by SELinux or SMACK.
72 50
73 If you are unsure how to answer this 51 If you are unsure how to answer this question, answer N.
74 52
75 config SECURITY_NETWORK 53 config SECURITY_NETWORK
76 bool "Socket and Networking Security H 54 bool "Socket and Networking Security Hooks"
77 depends on SECURITY 55 depends on SECURITY
78 help 56 help
79 This enables the socket and networki 57 This enables the socket and networking security hooks.
80 If enabled, a security module can us 58 If enabled, a security module can use these hooks to
81 implement socket and networking acce 59 implement socket and networking access controls.
82 If you are unsure how to answer this 60 If you are unsure how to answer this question, answer N.
83 61
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 62 config SECURITY_NETWORK_XFRM
94 bool "XFRM (IPSec) Networking Security 63 bool "XFRM (IPSec) Networking Security Hooks"
95 depends on XFRM && SECURITY_NETWORK 64 depends on XFRM && SECURITY_NETWORK
96 help 65 help
97 This enables the XFRM (IPSec) networ 66 This enables the XFRM (IPSec) networking security hooks.
98 If enabled, a security module can us 67 If enabled, a security module can use these hooks to
99 implement per-packet access controls 68 implement per-packet access controls based on labels
100 derived from IPSec policy. Non-IPSe 69 derived from IPSec policy. Non-IPSec communications are
101 designated as unlabelled, and only s 70 designated as unlabelled, and only sockets authorized
102 to communicate unlabelled data can s 71 to communicate unlabelled data can send without using
103 IPSec. 72 IPSec.
104 If you are unsure how to answer this 73 If you are unsure how to answer this question, answer N.
105 74
106 config SECURITY_PATH 75 config SECURITY_PATH
107 bool "Security hooks for pathname base 76 bool "Security hooks for pathname based access control"
108 depends on SECURITY 77 depends on SECURITY
109 help 78 help
110 This enables the security hooks for 79 This enables the security hooks for pathname based access control.
111 If enabled, a security module can us 80 If enabled, a security module can use these hooks to
112 implement pathname based access cont 81 implement pathname based access controls.
113 If you are unsure how to answer this 82 If you are unsure how to answer this question, answer N.
114 83
115 config INTEL_TXT 84 config INTEL_TXT
116 bool "Enable Intel(R) Trusted Executio 85 bool "Enable Intel(R) Trusted Execution Technology (Intel(R) TXT)"
117 depends on HAVE_INTEL_TXT 86 depends on HAVE_INTEL_TXT
118 help 87 help
119 This option enables support for boot 88 This option enables support for booting the kernel with the
120 Trusted Boot (tboot) module. This wi 89 Trusted Boot (tboot) module. This will utilize
121 Intel(R) Trusted Execution Technolog 90 Intel(R) Trusted Execution Technology to perform a measured launch
122 of the kernel. If the system does no 91 of the kernel. If the system does not support Intel(R) TXT, this
123 will have no effect. 92 will have no effect.
124 93
125 Intel TXT will provide higher assura 94 Intel TXT will provide higher assurance of system configuration and
126 initial state as well as data reset 95 initial state as well as data reset protection. This is used to
127 create a robust initial kernel measu 96 create a robust initial kernel measurement and verification, which
128 helps to ensure that kernel security 97 helps to ensure that kernel security mechanisms are functioning
129 correctly. This level of protection 98 correctly. This level of protection requires a root of trust outside
130 of the kernel itself. 99 of the kernel itself.
131 100
132 Intel TXT also helps solve real end 101 Intel TXT also helps solve real end user concerns about having
133 confidence that their hardware is ru 102 confidence that their hardware is running the VMM or kernel that
134 it was configured with, especially s 103 it was configured with, especially since they may be responsible for
135 providing such assurances to VMs and 104 providing such assurances to VMs and services running on it.
136 105
137 See <https://www.intel.com/technolog !! 106 See <http://www.intel.com/technology/security/> for more information
138 about Intel(R) TXT. 107 about Intel(R) TXT.
139 See <http://tboot.sourceforge.net> f 108 See <http://tboot.sourceforge.net> for more information about tboot.
140 See Documentation/arch/x86/intel_txt !! 109 See Documentation/intel_txt.txt for a description of how to enable
141 Intel TXT support in a kernel boot. 110 Intel TXT support in a kernel boot.
142 111
143 If you are unsure as to whether this 112 If you are unsure as to whether this is required, answer N.
144 113
145 config LSM_MMAP_MIN_ADDR 114 config LSM_MMAP_MIN_ADDR
146 int "Low address space for LSM to prot 115 int "Low address space for LSM to protect from user allocation"
147 depends on SECURITY && SECURITY_SELINU 116 depends on SECURITY && SECURITY_SELINUX
148 default 32768 if ARM || (ARM64 && COMP 117 default 32768 if ARM || (ARM64 && COMPAT)
149 default 65536 118 default 65536
150 help 119 help
151 This is the portion of low virtual m 120 This is the portion of low virtual memory which should be protected
152 from userspace allocation. Keeping 121 from userspace allocation. Keeping a user from writing to low pages
153 can help reduce the impact of kernel 122 can help reduce the impact of kernel NULL pointer bugs.
154 123
155 For most ia64, ppc64 and x86 users w 124 For most ia64, ppc64 and x86 users with lots of address space
156 a value of 65536 is reasonable and s 125 a value of 65536 is reasonable and should cause no problems.
157 On arm and other archs it should not 126 On arm and other archs it should not be higher than 32768.
158 Programs which use vm86 functionalit 127 Programs which use vm86 functionality or have some need to map
159 this low address space will need the 128 this low address space will need the permission specific to the
160 systems running LSM. 129 systems running LSM.
161 130
>> 131 config HAVE_HARDENED_USERCOPY_ALLOCATOR
>> 132 bool
>> 133 help
>> 134 The heap allocator implements __check_heap_object() for
>> 135 validating memory ranges against heap object sizes in
>> 136 support of CONFIG_HARDENED_USERCOPY.
>> 137
>> 138 config HAVE_ARCH_HARDENED_USERCOPY
>> 139 bool
>> 140 help
>> 141 The architecture supports CONFIG_HARDENED_USERCOPY by
>> 142 calling check_object_size() just before performing the
>> 143 userspace copies in the low level implementation of
>> 144 copy_to_user() and copy_from_user().
>> 145
162 config HARDENED_USERCOPY 146 config HARDENED_USERCOPY
163 bool "Harden memory copies between ker 147 bool "Harden memory copies between kernel and userspace"
164 imply STRICT_DEVMEM !! 148 depends on HAVE_ARCH_HARDENED_USERCOPY
>> 149 depends on HAVE_HARDENED_USERCOPY_ALLOCATOR
>> 150 select BUG
165 help 151 help
166 This option checks for obviously wro 152 This option checks for obviously wrong memory regions when
167 copying memory to/from the kernel (v 153 copying memory to/from the kernel (via copy_to_user() and
168 copy_from_user() functions) by rejec 154 copy_from_user() functions) by rejecting memory ranges that
169 are larger than the specified heap o 155 are larger than the specified heap object, span multiple
170 separately allocated pages, are not !! 156 separately allocates pages, are not on the process stack,
171 or are part of the kernel text. This !! 157 or are part of the kernel text. This kills entire classes
172 of heap overflow exploits and simila 158 of heap overflow exploits and similar kernel memory exposures.
173 159
174 config FORTIFY_SOURCE !! 160 config HARDENED_USERCOPY_PAGESPAN
175 bool "Harden common str/mem functions !! 161 bool "Refuse to copy allocations that span multiple pages"
176 depends on ARCH_HAS_FORTIFY_SOURCE !! 162 depends on HARDENED_USERCOPY
177 # https://github.com/llvm/llvm-project !! 163 depends on EXPERT
178 depends on !CC_IS_CLANG || !X86_32 !! 164 help
179 help !! 165 When a multi-page allocation is done without __GFP_COMP,
180 Detect overflows of buffers in commo !! 166 hardened usercopy will reject attempts to copy it. There are,
181 where the compiler can determine and !! 167 however, several cases of this in the kernel that have not all
182 !! 168 been removed. This config is intended to be used only while
183 config STATIC_USERMODEHELPER !! 169 trying to find such users.
184 bool "Force all usermode helper calls !! 170
185 help !! 171 source security/selinux/Kconfig
186 By default, the kernel can call many !! 172 source security/smack/Kconfig
187 binary programs through the "usermod !! 173 source security/tomoyo/Kconfig
188 interface. Some of these binaries a !! 174 source security/apparmor/Kconfig
189 either in the kernel code itself, or !! 175 source security/loadpin/Kconfig
190 option. However, some of these are !! 176 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" <<
228 177
229 source "security/integrity/Kconfig" !! 178 source security/integrity/Kconfig
230 179
231 choice 180 choice
232 prompt "First legacy 'major LSM' to be !! 181 prompt "Default security module"
233 default DEFAULT_SECURITY_SELINUX if SE 182 default DEFAULT_SECURITY_SELINUX if SECURITY_SELINUX
234 default DEFAULT_SECURITY_SMACK if SECU 183 default DEFAULT_SECURITY_SMACK if SECURITY_SMACK
235 default DEFAULT_SECURITY_TOMOYO if SEC 184 default DEFAULT_SECURITY_TOMOYO if SECURITY_TOMOYO
236 default DEFAULT_SECURITY_APPARMOR if S 185 default DEFAULT_SECURITY_APPARMOR if SECURITY_APPARMOR
237 default DEFAULT_SECURITY_DAC 186 default DEFAULT_SECURITY_DAC
238 187
239 help 188 help
240 This choice is there only for conver !! 189 Select the security module that will be used by default if the
241 in old kernel configs to CONFIG_LSM !! 190 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 <<
247 191
248 config DEFAULT_SECURITY_SELINUX 192 config DEFAULT_SECURITY_SELINUX
249 bool "SELinux" if SECURITY_SEL 193 bool "SELinux" if SECURITY_SELINUX=y
250 194
251 config DEFAULT_SECURITY_SMACK 195 config DEFAULT_SECURITY_SMACK
252 bool "Simplified Mandatory Acc 196 bool "Simplified Mandatory Access Control" if SECURITY_SMACK=y
253 197
254 config DEFAULT_SECURITY_TOMOYO 198 config DEFAULT_SECURITY_TOMOYO
255 bool "TOMOYO" if SECURITY_TOMO 199 bool "TOMOYO" if SECURITY_TOMOYO=y
256 200
257 config DEFAULT_SECURITY_APPARMOR 201 config DEFAULT_SECURITY_APPARMOR
258 bool "AppArmor" if SECURITY_AP 202 bool "AppArmor" if SECURITY_APPARMOR=y
259 203
260 config DEFAULT_SECURITY_DAC 204 config DEFAULT_SECURITY_DAC
261 bool "Unix Discretionary Acces 205 bool "Unix Discretionary Access Controls"
262 206
263 endchoice 207 endchoice
264 208
265 config LSM !! 209 config DEFAULT_SECURITY
266 string "Ordered list of enabled LSMs" !! 210 string
267 default "landlock,lockdown,yama,loadpi !! 211 default "selinux" if DEFAULT_SECURITY_SELINUX
268 default "landlock,lockdown,yama,loadpi !! 212 default "smack" if DEFAULT_SECURITY_SMACK
269 default "landlock,lockdown,yama,loadpi !! 213 default "tomoyo" if DEFAULT_SECURITY_TOMOYO
270 default "landlock,lockdown,yama,loadpi !! 214 default "apparmor" if DEFAULT_SECURITY_APPARMOR
271 default "landlock,lockdown,yama,loadpi !! 215 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" <<
282 216
283 source "security/ccsecurity/Kconfig" !! 217 source security/ccsecurity/Kconfig
284 218
285 endmenu 219 endmenu
286 220
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