#
#
# N.B Hardening command line parameters:
-# page_alloc.shuffle=1
# iommu=force (does it help against DMA attacks?)
-# slub_debug=FZ (slow)
# loadpin.enforce=1
-# debugfs=no-mount (or off if possible)
#
# Mitigations of CPU vulnerabilities:
# Аrch-independent:
# ssbd=force-on
#
# Should NOT be set:
-# nokaslr
# sysrq_always_enabled
# arm64.nobti
# arm64.nopauth
# [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
# when the tool doesn't check the cmdline.
+ efi_not_set = KconfigCheck('-', '-', 'EFI', 'is not set')
+ cc_is_gcc = KconfigCheck('-', '-', 'CC_IS_GCC', 'y')
+ cc_is_clang = KconfigCheck('-', '-', 'CC_IS_CLANG', 'y')
+
modules_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'MODULES', 'is not set')
devmem_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'DEVMEM', 'is not set') # refers to LOCKDOWN
bpf_syscall_not_set = KconfigCheck('cut_attack_surface', 'lockdown', 'BPF_SYSCALL', 'is not set') # refers to LOCKDOWN
- efi_not_set = KconfigCheck('cut_attack_surface', 'my', 'EFI', 'is not set')
# 'self_protection', 'defconfig'
l += [KconfigCheck('self_protection', 'defconfig', 'BUG', 'y')]
l += [KconfigCheck('self_protection', 'defconfig', 'SLUB_DEBUG', 'y')]
- l += [KconfigCheck('self_protection', 'defconfig', 'GCC_PLUGINS', 'y')]
+ l += [AND(KconfigCheck('self_protection', 'defconfig', 'GCC_PLUGINS', 'y'),
+ cc_is_gcc)]
l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR', 'y'),
KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR', 'y'),
KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_REGULAR', 'y'),
l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_CREDENTIALS', 'y')]
l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_NOTIFIERS', 'y')]
l += [KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y')]
- l += [KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_LATENT_ENTROPY', 'y')]
+ l += [AND(KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_LATENT_ENTROPY', 'y'),
+ cc_is_gcc)]
l += [KconfigCheck('self_protection', 'kspp', 'KFENCE', 'y')]
l += [KconfigCheck('self_protection', 'kspp', 'WERROR', 'y')]
l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y')]
l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set')] # true if IOMMU_DEFAULT_DMA_STRICT is set
l += [KconfigCheck('self_protection', 'kspp', 'ZERO_CALL_USED_REGS', 'y')]
randstruct_is_set = KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_RANDSTRUCT', 'y')
- l += [randstruct_is_set]
+ l += [AND(randstruct_is_set, cc_is_gcc)]
hardened_usercopy_is_set = KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y')
l += [hardened_usercopy_is_set]
l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
# That brings higher performance penalty.
if arch in ('X86_64', 'ARM64', 'X86_32'):
stackleak_is_set = KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STACKLEAK', 'y')
- l += [stackleak_is_set]
+ l += [AND(stackleak_is_set, cc_is_gcc)]
l += [KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y')]
if arch in ('X86_64', 'X86_32'):
l += [KconfigCheck('self_protection', 'kspp', 'SCHED_CORE', 'y')]
l += [KconfigCheck('self_protection', 'clipos', 'RANDOM_TRUST_BOOTLOADER', 'is not set')]
l += [KconfigCheck('self_protection', 'clipos', 'RANDOM_TRUST_CPU', 'is not set')]
l += [AND(KconfigCheck('self_protection', 'clipos', 'GCC_PLUGIN_RANDSTRUCT_PERFORMANCE', 'is not set'),
- randstruct_is_set)]
+ randstruct_is_set,
+ cc_is_gcc)]
if arch in ('X86_64', 'ARM64', 'X86_32'):
l += [AND(KconfigCheck('self_protection', 'clipos', 'STACKLEAK_METRICS', 'is not set'),
- stackleak_is_set)]
+ stackleak_is_set,
+ cc_is_gcc)]
l += [AND(KconfigCheck('self_protection', 'clipos', 'STACKLEAK_RUNTIME_DISABLE', 'is not set'),
- stackleak_is_set)]
+ stackleak_is_set,
+ cc_is_gcc)]
if arch in ('X86_64', 'X86_32'):
l += [AND(KconfigCheck('self_protection', 'clipos', 'INTEL_IOMMU_DEFAULT_ON', 'y'),
iommu_support_is_set)]
# required for the cmdline parameters. That would make the checks
# very complex and not give a 100% guarantee anyway.
+ # 'self_protection', 'defconfig'
if arch == 'ARM64':
l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', 'full'),
AND(KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y'),
l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', '1'),
CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set'))]
+ # 'self_protection', 'kspp'
l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', '1'),
AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y'),
CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', 'is not set')))]
l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', '0'),
AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set'),
CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', 'is not set')))]
+ # The cmdline checks compatible with the kconfig recommendations of the KSPP project...
+ l += [CmdlineCheck('self_protection', 'kspp', 'nokaslr', 'is not set')]
l += [OR(CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', '1'),
AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y'),
CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', 'is not set')))]
l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', '0'),
AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
- CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', 'is not set')))]
+ CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', 'is not set')))] # ... the end
if arch in ('X86_64', 'ARM64', 'X86_32'):
l += [OR(CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', '1'),
AND(KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y'),
if arch in ('X86_64', 'X86_32'):
l += [CmdlineCheck('self_protection', 'kspp', 'pti', 'on')]
+ # 'self_protection', 'clipos'
+ l += [CmdlineCheck('self_protection', 'clipos', 'page_alloc.shuffle', '1')]
+
+ # 'cut_attack_surface', 'kspp'
if arch == 'X86_64':
l += [OR(CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'none'),
AND(KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y'),
CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'is not set')))]
- # TODO: add other
+ # 'cut_attack_surface', 'grsec'
+ # The cmdline checks compatible with the kconfig options disabled by grsecurity...
+ l += [OR(CmdlineCheck('cut_attack_surface', 'grsec', 'debugfs', 'off'),
+ KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set'))] # ... the end
def print_unknown_options(checklist, parsed_options):
def normalize_cmdline_options(option, value):
- # Handle special cases
+ # Don't normalize the cmdline option values if
+ # the Linux kernel doesn't use kstrtobool() for them
if option == 'pti':
- # Don't normalize the pti value since
- # the Linux kernel doesn't use kstrtobool() for pti.
# See pti_check_boottime_disable() in linux/arch/x86/mm/pti.c
return value
+ if option == 'debugfs':
+ # See debugfs_kernel() in fs/debugfs/inode.c
+ return value
# Implement a limited part of the kstrtobool() logic
if value in ('1', 'on', 'On', 'ON', 'y', 'Y', 'yes', 'Yes', 'YES'):
projects / kconfig-hardened-check.git / blobdiff