But nobody likes checking configs manually. So let the computers do their job!
__kconfig-hardened-check.py__ helps me to check the Linux kernel Kconfig option list
-against my hardening preferences for `x86_64`, which are based on the
-[KSPP recommended settings][1] and last public [grsecurity][2] patch (options
-which they disable).
+against my hardening preferences, which are based on the
-Please don't cry if my Python code looks like C. I'm just a kernel developer.
+ - [KSPP recommended settings][1],
+ - [CLIP OS kernel configuration][2],
+ - last public [grsecurity][3] patch (options which they disable).
+
+I also created [__Linux Kernel Defence Map__][4] that is a graphical representation of the
+relationships between these hardening features and the corresponding vulnerability classes
+or exploitation techniques.
+
+## Supported microarchitectures
+
+ - X86_64
+ - X86_32
+ - ARM64
+ - ARM
## Script output examples
### Usage
```
-#./kconfig-hardened-check.py
-usage: kconfig-hardened-check.py [-h] [-p] [-c CONFIG] [--debug]
+usage: kconfig-hardened-check.py [-h] [-p {X86_64,X86_32,ARM64,ARM}]
+ [-c CONFIG] [--debug] [--json]
Checks the hardening options in the Linux kernel config
optional arguments:
-h, --help show this help message and exit
- -p, --print print hardening preferences
+ -p {X86_64,X86_32,ARM64,ARM}, --print {X86_64,X86_32,ARM64,ARM}
+ print hardening preferences for selected architecture
-c CONFIG, --config CONFIG
check the config_file against these preferences
--debug enable internal debug mode
+ --json print results in JSON format
+
```
-### Script output for `Ubuntu 18.04 (Bionic Beaver)` kernel config
+### Script output for `Ubuntu 18.04 (Bionic Beaver with HWE)` kernel config
```
-#./kconfig-hardened-check.py -c config_files/ubuntu-bionic-generic.config
-[+] Checking "config_files/ubuntu-bionic-generic.config" against hardening preferences...
- option name | desired val | decision | reason || check result
- ===================================================================================================================
- CONFIG_BUG | y | ubuntu18 | self_protection || OK
- CONFIG_PAGE_TABLE_ISOLATION | y | ubuntu18 | self_protection || OK
- CONFIG_RETPOLINE | y | ubuntu18 | self_protection || OK
- CONFIG_X86_64 | y | ubuntu18 | self_protection || OK
- CONFIG_STRICT_KERNEL_RWX | y | ubuntu18 | self_protection || OK
- CONFIG_STRICT_MODULE_RWX | y | ubuntu18 | self_protection || OK
- CONFIG_DEBUG_WX | y | ubuntu18 | self_protection || OK
- CONFIG_RANDOMIZE_BASE | y | ubuntu18 | self_protection || OK
- CONFIG_RANDOMIZE_MEMORY | y | ubuntu18 | self_protection || OK
- CONFIG_CC_STACKPROTECTOR | y | ubuntu18 | self_protection || OK
- CONFIG_CC_STACKPROTECTOR_STRONG | y | ubuntu18 | self_protection || OK
- CONFIG_VMAP_STACK | y | ubuntu18 | self_protection || OK
- CONFIG_THREAD_INFO_IN_TASK | y | ubuntu18 | self_protection || OK
- CONFIG_SCHED_STACK_END_CHECK | y | ubuntu18 | self_protection || OK
- CONFIG_SLUB_DEBUG | y | ubuntu18 | self_protection || OK
- CONFIG_SLAB_FREELIST_HARDENED | y | ubuntu18 | self_protection || OK
- CONFIG_SLAB_FREELIST_RANDOM | y | ubuntu18 | self_protection || OK
- CONFIG_HARDENED_USERCOPY | y | ubuntu18 | self_protection || OK
- CONFIG_FORTIFY_SOURCE | y | ubuntu18 | self_protection || OK
- CONFIG_MODULE_SIG | y | ubuntu18 | self_protection || OK
- CONFIG_MODULE_SIG_ALL | y | ubuntu18 | self_protection || OK
- CONFIG_MODULE_SIG_SHA512 | y | ubuntu18 | self_protection || OK
- CONFIG_SYN_COOKIES | y | ubuntu18 | self_protection || OK
- CONFIG_DEFAULT_MMAP_MIN_ADDR | 65536 | ubuntu18 | self_protection || OK
- CONFIG_BUG_ON_DATA_CORRUPTION | y | kspp | self_protection || FAIL: "is not set"
- CONFIG_PAGE_POISONING | y | kspp | self_protection || FAIL: "is not set"
- CONFIG_GCC_PLUGINS | y | kspp | self_protection || FAIL: "is not set"
- CONFIG_GCC_PLUGIN_RANDSTRUCT | y | kspp | self_protection || FAIL: not found
- CONFIG_GCC_PLUGIN_STRUCTLEAK | y | kspp | self_protection || FAIL: not found
- CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF_ALL | y | kspp | self_protection || FAIL: not found
- CONFIG_GCC_PLUGIN_LATENT_ENTROPY | y | kspp | self_protection || FAIL: not found
- CONFIG_REFCOUNT_FULL | y | kspp | self_protection || FAIL: "is not set"
- CONFIG_DEBUG_LIST | y | kspp | self_protection || FAIL: "is not set"
- CONFIG_DEBUG_SG | y | kspp | self_protection || FAIL: "is not set"
- CONFIG_DEBUG_CREDENTIALS | y | kspp | self_protection || FAIL: "is not set"
- CONFIG_DEBUG_NOTIFIERS | y | kspp | self_protection || FAIL: "is not set"
- CONFIG_MODULE_SIG_FORCE | y | kspp | self_protection || FAIL: "is not set"
- CONFIG_HARDENED_USERCOPY_FALLBACK | is not set | kspp | self_protection || OK: not found
- CONFIG_GCC_PLUGIN_STACKLEAK | y | my | self_protection || FAIL: not found
- CONFIG_SLUB_DEBUG_ON | y | my | self_protection || FAIL: "is not set"
- CONFIG_SECURITY_DMESG_RESTRICT | y | my | self_protection || FAIL: "is not set"
- CONFIG_STATIC_USERMODEHELPER | y | my | self_protection || FAIL: "is not set"
- CONFIG_PAGE_POISONING_NO_SANITY | is not set | my | self_protection || OK: not found
- CONFIG_PAGE_POISONING_ZERO | is not set | my | self_protection || OK: not found
- CONFIG_SECURITY | y | ubuntu18 | security_policy || OK
- CONFIG_SECURITY_YAMA | y | ubuntu18 | security_policy || OK
- CONFIG_SECURITY_SELINUX_DISABLE | is not set | ubuntu18 | security_policy || OK
- CONFIG_SECCOMP | y | ubuntu18 | cut_attack_surface || OK
- CONFIG_SECCOMP_FILTER | y | ubuntu18 | cut_attack_surface || OK
- CONFIG_STRICT_DEVMEM | y | ubuntu18 | cut_attack_surface || OK
- CONFIG_ACPI_CUSTOM_METHOD | is not set | ubuntu18 | cut_attack_surface || OK
- CONFIG_COMPAT_BRK | is not set | ubuntu18 | cut_attack_surface || OK
- CONFIG_DEVKMEM | is not set | ubuntu18 | cut_attack_surface || OK
- CONFIG_COMPAT_VDSO | is not set | ubuntu18 | cut_attack_surface || OK
- CONFIG_X86_PTDUMP | is not set | ubuntu18 | cut_attack_surface || OK
- CONFIG_ZSMALLOC_STAT | is not set | ubuntu18 | cut_attack_surface || OK
- CONFIG_PAGE_OWNER | is not set | ubuntu18 | cut_attack_surface || OK
- CONFIG_DEBUG_KMEMLEAK | is not set | ubuntu18 | cut_attack_surface || OK
- CONFIG_BINFMT_AOUT | is not set | ubuntu18 | cut_attack_surface || OK: not found
- CONFIG_IO_STRICT_DEVMEM | y | kspp | cut_attack_surface || FAIL: "is not set"
- CONFIG_LEGACY_VSYSCALL_NONE | y | kspp | cut_attack_surface || FAIL: "is not set"
- CONFIG_BINFMT_MISC | is not set | kspp | cut_attack_surface || FAIL: "m"
- CONFIG_INET_DIAG | is not set | kspp | cut_attack_surface || FAIL: "m"
- CONFIG_KEXEC | is not set | kspp | cut_attack_surface || FAIL: "y"
- CONFIG_PROC_KCORE | is not set | kspp | cut_attack_surface || FAIL: "y"
- CONFIG_LEGACY_PTYS | is not set | kspp | cut_attack_surface || FAIL: "y"
- CONFIG_IA32_EMULATION | is not set | kspp | cut_attack_surface || FAIL: "y"
- CONFIG_X86_X32 | is not set | kspp | cut_attack_surface || FAIL: "y"
- CONFIG_MODIFY_LDT_SYSCALL | is not set | kspp | cut_attack_surface || FAIL: "y"
- CONFIG_HIBERNATION | is not set | kspp | cut_attack_surface || FAIL: "y"
- CONFIG_KPROBES | is not set |grsecurity| cut_attack_surface || FAIL: "y"
- CONFIG_UPROBES | is not set |grsecurity| cut_attack_surface || FAIL: "y"
- CONFIG_GENERIC_TRACER | is not set |grsecurity| cut_attack_surface || FAIL: "y"
- CONFIG_PROC_VMCORE | is not set |grsecurity| cut_attack_surface || FAIL: "y"
- CONFIG_PROC_PAGE_MONITOR | is not set |grsecurity| cut_attack_surface || FAIL: "y"
- CONFIG_USELIB | is not set |grsecurity| cut_attack_surface || FAIL: "y"
- CONFIG_CHECKPOINT_RESTORE | is not set |grsecurity| cut_attack_surface || FAIL: "y"
- CONFIG_USERFAULTFD | is not set |grsecurity| cut_attack_surface || FAIL: "y"
- CONFIG_HWPOISON_INJECT | is not set |grsecurity| cut_attack_surface || FAIL: "m"
- CONFIG_MEM_SOFT_DIRTY | is not set |grsecurity| cut_attack_surface || FAIL: "y"
- CONFIG_DEVPORT | is not set |grsecurity| cut_attack_surface || FAIL: "y"
- CONFIG_DEBUG_FS | is not set |grsecurity| cut_attack_surface || FAIL: "y"
- CONFIG_NOTIFIER_ERROR_INJECTION | is not set |grsecurity| cut_attack_surface || FAIL: "m"
- CONFIG_KEXEC_FILE | is not set | my | cut_attack_surface || FAIL: "y"
- CONFIG_LIVEPATCH | is not set | my | cut_attack_surface || FAIL: "y"
- CONFIG_USER_NS | is not set | my | cut_attack_surface || FAIL: "y"
- CONFIG_IP_DCCP | is not set | my | cut_attack_surface || FAIL: "m"
- CONFIG_IP_SCTP | is not set | my | cut_attack_surface || FAIL: "m"
- CONFIG_FTRACE | is not set | my | cut_attack_surface || FAIL: "y"
- CONFIG_PROFILING | is not set | my | cut_attack_surface || FAIL: "y"
- CONFIG_BPF_JIT | is not set | my | cut_attack_surface || FAIL: "y"
- CONFIG_BPF_SYSCALL | is not set | my | cut_attack_surface || FAIL: "y"
- CONFIG_ARCH_MMAP_RND_BITS | 32 | my |userspace_protection|| FAIL: "28"
- CONFIG_LKDTM | m | my | feature_test || FAIL: "is not set"
-
-[-] config check is NOT PASSED: 52 errors
+$ ./kconfig-hardened-check.py -c config_files/distros/ubuntu-bionic-generic.config
+[+] Trying to detect architecture in "config_files/distros/ubuntu-bionic-generic.config"...
+[+] Detected architecture: X86_64
+[+] Checking "config_files/distros/ubuntu-bionic-generic.config" against hardening preferences...
+ option name | desired val | decision | reason | check result
+=========================================================================================================================
+CONFIG_BUG | y |defconfig | self_protection | OK
+CONFIG_STRICT_KERNEL_RWX | y |defconfig | self_protection | OK
+CONFIG_STACKPROTECTOR_STRONG | y |defconfig | self_protection | OK
+CONFIG_SLUB_DEBUG | y |defconfig | self_protection | OK
+CONFIG_STRICT_MODULE_RWX | y |defconfig | self_protection | OK
+CONFIG_MICROCODE | y |defconfig | self_protection | OK
+CONFIG_RETPOLINE | y |defconfig | self_protection | OK
+CONFIG_X86_SMAP | y |defconfig | self_protection | OK
+CONFIG_X86_UMIP | y |defconfig | self_protection | OK: CONFIG_X86_INTEL_UMIP "y"
+CONFIG_IOMMU_SUPPORT | y |defconfig | self_protection | OK
+CONFIG_SYN_COOKIES | y |defconfig | self_protection | OK
+CONFIG_PAGE_TABLE_ISOLATION | y |defconfig | self_protection | OK
+CONFIG_RANDOMIZE_MEMORY | y |defconfig | self_protection | OK
+CONFIG_INTEL_IOMMU | y |defconfig | self_protection | OK
+CONFIG_AMD_IOMMU | y |defconfig | self_protection | OK
+CONFIG_VMAP_STACK | y |defconfig | self_protection | OK
+CONFIG_RANDOMIZE_BASE | y |defconfig | self_protection | OK
+CONFIG_THREAD_INFO_IN_TASK | y |defconfig | self_protection | OK
+CONFIG_BUG_ON_DATA_CORRUPTION | y | kspp | self_protection | FAIL: "is not set"
+CONFIG_DEBUG_WX | y | kspp | self_protection | OK
+CONFIG_SCHED_STACK_END_CHECK | y | kspp | self_protection | OK
+CONFIG_SLAB_FREELIST_HARDENED | y | kspp | self_protection | OK
+CONFIG_SLAB_FREELIST_RANDOM | y | kspp | self_protection | OK
+CONFIG_SHUFFLE_PAGE_ALLOCATOR | y | kspp | self_protection | OK
+CONFIG_FORTIFY_SOURCE | y | kspp | self_protection | OK
+CONFIG_GCC_PLUGINS | y | kspp | self_protection | FAIL: not found
+CONFIG_GCC_PLUGIN_RANDSTRUCT | y | kspp | self_protection | FAIL: not found
+CONFIG_GCC_PLUGIN_LATENT_ENTROPY | y | kspp | self_protection | FAIL: not found
+CONFIG_DEBUG_LIST | y | kspp | self_protection | FAIL: "is not set"
+CONFIG_DEBUG_SG | y | kspp | self_protection | FAIL: "is not set"
+CONFIG_DEBUG_CREDENTIALS | y | kspp | self_protection | FAIL: "is not set"
+CONFIG_DEBUG_NOTIFIERS | y | kspp | self_protection | FAIL: "is not set"
+CONFIG_HARDENED_USERCOPY | y | kspp | self_protection | OK
+CONFIG_HARDENED_USERCOPY_FALLBACK | is not set | kspp | self_protection | FAIL: "y"
+CONFIG_MODULE_SIG | y | kspp | self_protection | OK
+CONFIG_MODULE_SIG_ALL | y | kspp | self_protection | OK
+CONFIG_MODULE_SIG_SHA512 | y | kspp | self_protection | OK
+CONFIG_MODULE_SIG_FORCE | y | kspp | self_protection | FAIL: "is not set"
+CONFIG_DEFAULT_MMAP_MIN_ADDR | 65536 | kspp | self_protection | OK
+CONFIG_REFCOUNT_FULL | y | kspp | self_protection | FAIL: "is not set"
+CONFIG_INIT_STACK_ALL | y | clipos | self_protection | FAIL: not found
+CONFIG_INIT_ON_ALLOC_DEFAULT_ON | y | clipos | self_protection | OK
+CONFIG_INIT_ON_FREE_DEFAULT_ON | y | clipos | self_protection | OK: CONFIG_PAGE_POISONING "y"
+CONFIG_SECURITY_DMESG_RESTRICT | y | clipos | self_protection | FAIL: "is not set"
+CONFIG_DEBUG_VIRTUAL | y | clipos | self_protection | FAIL: "is not set"
+CONFIG_STATIC_USERMODEHELPER | y | clipos | self_protection | FAIL: "is not set"
+CONFIG_SLAB_MERGE_DEFAULT | is not set | clipos | self_protection | FAIL: "y"
+CONFIG_GCC_PLUGIN_RANDSTRUCT_PERFORMANCE | is not set | clipos | self_protection | FAIL: CONFIG_GCC_PLUGIN_RANDSTRUCT is needed
+CONFIG_GCC_PLUGIN_STACKLEAK | y | clipos | self_protection | FAIL: not found
+CONFIG_STACKLEAK_METRICS | is not set | clipos | self_protection | FAIL: CONFIG_GCC_PLUGIN_STACKLEAK is needed
+CONFIG_STACKLEAK_RUNTIME_DISABLE | is not set | clipos | self_protection | FAIL: CONFIG_GCC_PLUGIN_STACKLEAK is needed
+CONFIG_RANDOM_TRUST_CPU | is not set | clipos | self_protection | FAIL: "y"
+CONFIG_INTEL_IOMMU_SVM | y | clipos | self_protection | OK
+CONFIG_INTEL_IOMMU_DEFAULT_ON | y | clipos | self_protection | FAIL: "is not set"
+CONFIG_SLUB_DEBUG_ON | y | my | self_protection | FAIL: "is not set"
+CONFIG_RESET_ATTACK_MITIGATION | y | my | self_protection | OK
+CONFIG_AMD_IOMMU_V2 | y | my | self_protection | FAIL: "m"
+CONFIG_SECURITY | y |defconfig | security_policy | OK
+CONFIG_SECURITY_WRITABLE_HOOKS | is not set |defconfig | security_policy | OK: not found
+CONFIG_SECURITY_YAMA | y | kspp | security_policy | OK
+CONFIG_SECURITY_LOADPIN | y | my | security_policy | FAIL: "is not set"
+CONFIG_SECURITY_LOCKDOWN_LSM | y | my | security_policy | FAIL: not found
+CONFIG_SECURITY_LOCKDOWN_LSM_EARLY | y | my | security_policy | FAIL: not found
+CONFIG_LOCK_DOWN_KERNEL_FORCE_CONFIDENTIALITY| y | my | security_policy | FAIL: not found
+CONFIG_SECURITY_SAFESETID | y | my | security_policy | OK
+CONFIG_SECCOMP | y |defconfig | cut_attack_surface | OK
+CONFIG_SECCOMP_FILTER | y |defconfig | cut_attack_surface | OK
+CONFIG_STRICT_DEVMEM | y |defconfig | cut_attack_surface | OK
+CONFIG_MODULES | is not set | kspp | cut_attack_surface | FAIL: "y"
+CONFIG_DEVMEM | is not set | kspp | cut_attack_surface | FAIL: "y"
+CONFIG_IO_STRICT_DEVMEM | y | kspp | cut_attack_surface | FAIL: "is not set"
+CONFIG_ACPI_CUSTOM_METHOD | is not set | kspp | cut_attack_surface | OK
+CONFIG_COMPAT_BRK | is not set | kspp | cut_attack_surface | OK
+CONFIG_DEVKMEM | is not set | kspp | cut_attack_surface | OK
+CONFIG_COMPAT_VDSO | is not set | kspp | cut_attack_surface | OK
+CONFIG_BINFMT_MISC | is not set | kspp | cut_attack_surface | FAIL: "m"
+CONFIG_INET_DIAG | is not set | kspp | cut_attack_surface | FAIL: "m"
+CONFIG_KEXEC | is not set | kspp | cut_attack_surface | FAIL: "y"
+CONFIG_PROC_KCORE | is not set | kspp | cut_attack_surface | FAIL: "y"
+CONFIG_LEGACY_PTYS | is not set | kspp | cut_attack_surface | FAIL: "y"
+CONFIG_HIBERNATION | is not set | kspp | cut_attack_surface | FAIL: "y"
+CONFIG_LEGACY_VSYSCALL_NONE | y | kspp | cut_attack_surface | FAIL: "is not set"
+CONFIG_IA32_EMULATION | is not set | kspp | cut_attack_surface | FAIL: "y"
+CONFIG_X86_X32 | is not set | kspp | cut_attack_surface | FAIL: "y"
+CONFIG_MODIFY_LDT_SYSCALL | is not set | kspp | cut_attack_surface | FAIL: "y"
+CONFIG_X86_PTDUMP | is not set |grsecurity| cut_attack_surface | OK
+CONFIG_ZSMALLOC_STAT | is not set |grsecurity| cut_attack_surface | OK
+CONFIG_PAGE_OWNER | is not set |grsecurity| cut_attack_surface | OK
+CONFIG_DEBUG_KMEMLEAK | is not set |grsecurity| cut_attack_surface | OK
+CONFIG_BINFMT_AOUT | is not set |grsecurity| cut_attack_surface | OK: not found
+CONFIG_KPROBES | is not set |grsecurity| cut_attack_surface | FAIL: "y"
+CONFIG_UPROBES | is not set |grsecurity| cut_attack_surface | FAIL: "y"
+CONFIG_GENERIC_TRACER | is not set |grsecurity| cut_attack_surface | FAIL: "y"
+CONFIG_PROC_VMCORE | is not set |grsecurity| cut_attack_surface | FAIL: "y"
+CONFIG_PROC_PAGE_MONITOR | is not set |grsecurity| cut_attack_surface | FAIL: "y"
+CONFIG_USELIB | is not set |grsecurity| cut_attack_surface | FAIL: "y"
+CONFIG_CHECKPOINT_RESTORE | is not set |grsecurity| cut_attack_surface | FAIL: "y"
+CONFIG_USERFAULTFD | is not set |grsecurity| cut_attack_surface | FAIL: "y"
+CONFIG_HWPOISON_INJECT | is not set |grsecurity| cut_attack_surface | FAIL: "m"
+CONFIG_MEM_SOFT_DIRTY | is not set |grsecurity| cut_attack_surface | FAIL: "y"
+CONFIG_DEVPORT | is not set |grsecurity| cut_attack_surface | FAIL: "y"
+CONFIG_DEBUG_FS | is not set |grsecurity| cut_attack_surface | FAIL: "y"
+CONFIG_NOTIFIER_ERROR_INJECTION | is not set |grsecurity| cut_attack_surface | FAIL: "m"
+CONFIG_ACPI_TABLE_UPGRADE | is not set | lockdown | cut_attack_surface | FAIL: "y"
+CONFIG_ACPI_APEI_EINJ | is not set | lockdown | cut_attack_surface | FAIL: "m"
+CONFIG_PROFILING | is not set | lockdown | cut_attack_surface | FAIL: "y"
+CONFIG_BPF_SYSCALL | is not set | lockdown | cut_attack_surface | FAIL: "y"
+CONFIG_MMIOTRACE_TEST | is not set | lockdown | cut_attack_surface | OK
+CONFIG_KSM | is not set | clipos | cut_attack_surface | FAIL: "y"
+CONFIG_KALLSYMS | is not set | clipos | cut_attack_surface | FAIL: "y"
+CONFIG_X86_VSYSCALL_EMULATION | is not set | clipos | cut_attack_surface | FAIL: "y"
+CONFIG_MAGIC_SYSRQ | is not set | clipos | cut_attack_surface | FAIL: "y"
+CONFIG_KEXEC_FILE | is not set | clipos | cut_attack_surface | FAIL: "y"
+CONFIG_USER_NS | is not set | clipos | cut_attack_surface | FAIL: "y"
+CONFIG_LDISC_AUTOLOAD | is not set | clipos | cut_attack_surface | FAIL: "y"
+CONFIG_MMIOTRACE | is not set | my | cut_attack_surface | FAIL: "y"
+CONFIG_LIVEPATCH | is not set | my | cut_attack_surface | FAIL: "y"
+CONFIG_IP_DCCP | is not set | my | cut_attack_surface | FAIL: "m"
+CONFIG_IP_SCTP | is not set | my | cut_attack_surface | FAIL: "m"
+CONFIG_FTRACE | is not set | my | cut_attack_surface | FAIL: "y"
+CONFIG_BPF_JIT | is not set | my | cut_attack_surface | FAIL: "y"
+CONFIG_VIDEO_VIVID | is not set | my | cut_attack_surface | FAIL: "m"
+CONFIG_ARCH_MMAP_RND_BITS | 32 | clipos |userspace_hardening | FAIL: "28"
+
+[+] config check is finished: 'OK' - 50 / 'FAIL' - 73
```
-__Go and fix them all!__
+## kconfig-hardened-check versioning
+
+I usually update the kernel hardening recommendations after each Linux kernel release.
+
+So the version of `kconfig-hardened-check` is associated with the corresponding version of the kernel.
+
+The version format is: __[major_number].[kernel_version]__
+
+The current version of `kconfig-hardened-check` is __0.5.3__, it's marked with the git tag.
+
+
+## Questions and answers
+
+__Q:__ How disabling `CONFIG_USER_NS` cuts the attack surface? It's needed for containers!
+
+__A:__ Yes, the `CONFIG_USER_NS` option provides some isolation between the userspace programs,
+but the script recommends disabling it to cut the attack surface __of the kernel__.
+
+The rationale:
+
+ - A nice LWN article about the corresponding LKML discussion: https://lwn.net/Articles/673597/
+
+ - A twitter thread about `CONFIG_USER_NS` and security: https://twitter.com/robertswiecki/status/1095447678949953541
+
+<br />
+
+__Q:__ Why `CONFIG_GCC_PLUGINS` is automatically disabled during the kernel compilation?
+
+__A:__ It means that your gcc doesn't support plugins. For example, if you have `gcc-7` on Ubuntu,
+try to install `gcc-7-plugin-dev` package, it should help.
+
+<br />
+
+__Q:__ KSPP and CLIP OS recommend `CONFIG_PANIC_ON_OOPS=y`. Why doesn't this tool do the same?
+
+__A:__ I personally don't support this recommendation because it provides easy denial-of-service
+attacks for the whole system (kernel oops is not a rare situation). I think having `CONFIG_BUG` is enough here --
+if we have a kernel oops in the process context, the offending/attacking process is killed.
[1]: http://kernsec.org/wiki/index.php/Kernel_Self_Protection_Project/Recommended_Settings
-[2]: https://grsecurity.net/
+[2]: https://docs.clip-os.org/clipos/kernel.html#configuration
+[3]: https://grsecurity.net/
+[4]: https://github.com/a13xp0p0v/linux-kernel-defence-map
projects / kconfig-hardened-check.git / blobdiff