Kconfig hardened check
Motivation
There are plenty of Linux kernel hardening config options. A lot of them are not enabled by the major distros. We have to enable these options ourselves to make our systems more secure.
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 and last public grsecurity patch (options
which they disable).
Please don't cry if my Python code looks like C. I'm just a kernel developer.
Script output examples
Usage
#./kconfig-hardened-check.py
Usage: ./kconfig-hardened-check.py [-p | -c <config_file>]
-p, --print
print hardening preferences
-c <config_file>, --config=<config_file>
check the config_file against these preferences
Script output for Ubuntu 18.04 (Bionic Beaver) kernel config
./kconfig-hardened-check.py -c ubuntu-bionic-generic.config
[+] Checking "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 || FAIL: 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 || FAIL: not found
CONFIG_PAGE_POISONING_ZERO | is not set | my | self_protection || FAIL: 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_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: 55 errorsGo and fix them all!