4 # This tool helps me to check Linux kernel options against
5 # my security hardening preferences for X86_64, ARM64, X86_32, and ARM.
6 # Let the computers do their job!
8 # Author: Alexander Popov <alex.popov@linux.com>
10 # Please don't cry if my Python code looks like C.
13 # N.B Missing hardening command line parameters:
14 # iommu=force (does it help against DMA attacks?)
16 # Hardware tag-based KASAN with arm64 Memory Tagging Extension (MTE):
18 # kasan.stacktrace=off
21 # N.B. Hardening sysctls:
22 # kernel.kptr_restrict=2 (or 1?)
23 # kernel.dmesg_restrict=1 (also see the kconfig option)
24 # kernel.perf_event_paranoid=3
25 # kernel.kexec_load_disabled=1
26 # kernel.yama.ptrace_scope=3
27 # user.max_user_namespaces=0
28 # what about bpf_jit_enable?
29 # kernel.unprivileged_bpf_disabled=1
30 # net.core.bpf_jit_harden=2
31 # vm.unprivileged_userfaultfd=0
32 # (at first, it disabled unprivileged userfaultfd,
33 # and since v5.11 it enables unprivileged userfaultfd for user-mode only)
34 # vm.mmap_min_addr has a good value
35 # dev.tty.ldisc_autoload=0
36 # fs.protected_symlinks=1
37 # fs.protected_hardlinks=1
38 # fs.protected_fifos=2
39 # fs.protected_regular=2
41 # kernel.modules_disabled=1
42 # kernel.randomize_va_space = 2
43 # nosmt sysfs control file
46 # pylint: disable=missing-module-docstring,missing-class-docstring,missing-function-docstring
47 # pylint: disable=line-too-long,invalid-name,too-many-branches,too-many-statements
51 from argparse import ArgumentParser
52 from collections import OrderedDict
55 from .__about__ import __version__
57 SIMPLE_OPTION_TYPES = ('kconfig', 'version', 'cmdline')
60 def __init__(self, reason, decision, name, expected):
61 assert(name and name == name.strip() and len(name.split()) == 1), \
62 'invalid name "{}" for {}'.format(name, self.__class__.__name__)
65 assert(decision and decision == decision.strip() and len(decision.split()) == 1), \
66 'invalid decision "{}" for "{}" check'.format(decision, name)
67 self.decision = decision
69 assert(reason and reason == reason.strip() and len(reason.split()) == 1), \
70 'invalid reason "{}" for "{}" check'.format(reason, name)
73 assert(expected and expected == expected.strip()), \
74 'invalid expected value "{}" for "{}" check (1)'.format(expected, name)
75 val_len = len(expected.split())
77 assert(expected == 'is not set' or expected == 'is not off'), \
78 'invalid expected value "{}" for "{}" check (2)'.format(expected, name)
80 assert(expected == 'is present'), \
81 'invalid expected value "{}" for "{}" check (3)'.format(expected, name)
83 assert(val_len == 1), \
84 'invalid expected value "{}" for "{}" check (4)'.format(expected, name)
85 self.expected = expected
95 # handle the 'is present' check
96 if self.expected == 'is present':
97 if self.state is None:
98 self.result = 'FAIL: is not present'
100 self.result = 'OK: is present'
103 # handle the 'is not off' option check
104 if self.expected == 'is not off':
105 if self.state == 'off':
106 self.result = 'FAIL: is off'
107 if self.state == '0':
108 self.result = 'FAIL: is off, "0"'
109 elif self.state is None:
110 self.result = 'FAIL: is off, not found'
112 self.result = 'OK: is not off, "' + self.state + '"'
115 # handle the option value check
116 if self.expected == self.state:
118 elif self.state is None:
119 if self.expected == 'is not set':
120 self.result = 'OK: is not found'
122 self.result = 'FAIL: is not found'
124 self.result = 'FAIL: "' + self.state + '"'
126 def table_print(self, _mode, with_results):
127 print('{:<40}|{:^7}|{:^12}|{:^10}|{:^18}'.format(self.name, self.type, self.expected, self.decision, self.reason), end='')
129 print('| {}'.format(self.result), end='')
131 def json_dump(self, with_results):
132 dump = [self.name, self.type, self.expected, self.decision, self.reason]
134 dump.append(self.result)
138 class KconfigCheck(OptCheck):
139 def __init__(self, *args, **kwargs):
140 super().__init__(*args, **kwargs)
141 self.name = 'CONFIG_' + self.name
148 class CmdlineCheck(OptCheck):
155 def __init__(self, ver_expected):
156 assert(ver_expected and isinstance(ver_expected, tuple) and len(ver_expected) == 2), \
157 'invalid version "{}" for VersionCheck'.format(ver_expected)
158 self.ver_expected = ver_expected
167 if self.ver[0] > self.ver_expected[0]:
168 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
170 if self.ver[0] < self.ver_expected[0]:
171 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
173 if self.ver[1] >= self.ver_expected[1]:
174 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
176 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
178 def table_print(self, _mode, with_results):
179 ver_req = 'kernel version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
180 print('{:<91}'.format(ver_req), end='')
182 print('| {}'.format(self.result), end='')
185 class ComplexOptCheck:
186 def __init__(self, *opts):
189 'empty {} check'.format(self.__class__.__name__)
190 assert(len(self.opts) != 1), \
191 'useless {} check: {}'.format(self.__class__.__name__, opts)
192 assert(isinstance(opts[0], (KconfigCheck, CmdlineCheck))), \
193 'invalid {} check: {}'.format(self.__class__.__name__, opts)
202 return self.opts[0].name
206 return self.opts[0].expected
208 def table_print(self, mode, with_results):
209 if mode == 'verbose':
210 print(' {:87}'.format('<<< ' + self.__class__.__name__ + ' >>>'), end='')
212 print('| {}'.format(self.result), end='')
215 o.table_print(mode, with_results)
218 o.table_print(mode, False)
220 print('| {}'.format(self.result), end='')
222 def json_dump(self, with_results):
223 dump = self.opts[0].json_dump(False)
225 dump.append(self.result)
229 class OR(ComplexOptCheck):
230 # self.opts[0] is the option that this OR-check is about.
232 # OR(<X_is_hardened>, <X_is_disabled>)
233 # OR(<X_is_hardened>, <old_X_is_hardened>)
235 for i, opt in enumerate(self.opts):
237 if opt.result.startswith('OK'):
238 self.result = opt.result
239 # Add more info for additional checks:
241 if opt.result == 'OK':
242 self.result = 'OK: {} is "{}"'.format(opt.name, opt.expected)
243 elif opt.result == 'OK: is not found':
244 self.result = 'OK: {} is not found'.format(opt.name)
245 elif opt.result == 'OK: is present':
246 self.result = 'OK: {} is present'.format(opt.name)
247 elif opt.result.startswith('OK: is not off'):
248 self.result = 'OK: {} is not off'.format(opt.name)
250 # VersionCheck provides enough info
251 assert(opt.result.startswith('OK: version')), \
252 'unexpected OK description "{}"'.format(opt.result)
254 self.result = self.opts[0].result
257 class AND(ComplexOptCheck):
258 # self.opts[0] is the option that this AND-check is about.
260 # AND(<suboption>, <main_option>)
261 # Suboption is not checked if checking of the main_option is failed.
262 # AND(<X_is_disabled>, <old_X_is_disabled>)
264 for i, opt in reversed(list(enumerate(self.opts))):
267 self.result = opt.result
269 if not opt.result.startswith('OK'):
270 # This FAIL is caused by additional checks,
271 # and not by the main option that this AND-check is about.
272 # Describe the reason of the FAIL.
273 if opt.result.startswith('FAIL: \"') or opt.result == 'FAIL: is not found':
274 self.result = 'FAIL: {} is not "{}"'.format(opt.name, opt.expected)
275 elif opt.result == 'FAIL: is not present':
276 self.result = 'FAIL: {} is not present'.format(opt.name)
277 elif opt.result == 'FAIL: is off' or opt.result == 'FAIL: is off, "0"':
278 self.result = 'FAIL: {} is off'.format(opt.name)
279 elif opt.result == 'FAIL: is off, not found':
280 self.result = 'FAIL: {} is off, not found'.format(opt.name)
282 # VersionCheck provides enough info
283 self.result = opt.result
284 assert(opt.result.startswith('FAIL: version')), \
285 'unexpected FAIL description "{}"'.format(opt.result)
289 def detect_arch(fname, archs):
290 with open(fname, 'r') as f:
291 arch_pattern = re.compile("CONFIG_[a-zA-Z0-9_]*=y")
293 for line in f.readlines():
294 if arch_pattern.match(line):
295 option, _ = line[7:].split('=', 1)
300 return None, 'more than one supported architecture is detected'
302 return None, 'failed to detect architecture'
306 def detect_kernel_version(fname):
307 with open(fname, 'r') as f:
308 ver_pattern = re.compile("# Linux/.* Kernel Configuration")
309 for line in f.readlines():
310 if ver_pattern.match(line):
314 ver_numbers = ver_str.split('.')
315 if len(ver_numbers) < 3 or not ver_numbers[0].isdigit() or not ver_numbers[1].isdigit():
316 msg = 'failed to parse the version "' + ver_str + '"'
318 return (int(ver_numbers[0]), int(ver_numbers[1])), None
319 return None, 'no kernel version detected'
322 def detect_compiler(fname):
325 with open(fname, 'r') as f:
326 gcc_version_pattern = re.compile("CONFIG_GCC_VERSION=[0-9]*")
327 clang_version_pattern = re.compile("CONFIG_CLANG_VERSION=[0-9]*")
328 for line in f.readlines():
329 if gcc_version_pattern.match(line):
330 gcc_version = line[19:-1]
331 if clang_version_pattern.match(line):
332 clang_version = line[21:-1]
333 if not gcc_version or not clang_version:
334 return None, 'no CONFIG_GCC_VERSION or CONFIG_CLANG_VERSION'
335 if gcc_version == '0' and clang_version != '0':
336 return 'CLANG ' + clang_version, 'OK'
337 if gcc_version != '0' and clang_version == '0':
338 return 'GCC ' + gcc_version, 'OK'
339 sys.exit('[!] ERROR: invalid GCC_VERSION and CLANG_VERSION: {} {}'.format(gcc_version, clang_version))
342 def add_kconfig_checks(l, arch):
343 # Calling the KconfigCheck class constructor:
344 # KconfigCheck(reason, decision, name, expected)
346 # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
347 # when the tool doesn't check the cmdline.
349 efi_not_set = KconfigCheck('-', '-', 'EFI', 'is not set')
350 cc_is_gcc = KconfigCheck('-', '-', 'CC_IS_GCC', 'y') # exists since v4.18
351 cc_is_clang = KconfigCheck('-', '-', 'CC_IS_CLANG', 'y') # exists since v4.18
353 modules_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'MODULES', 'is not set')
354 devmem_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'DEVMEM', 'is not set') # refers to LOCKDOWN
355 bpf_syscall_not_set = KconfigCheck('cut_attack_surface', 'lockdown', 'BPF_SYSCALL', 'is not set') # refers to LOCKDOWN
357 # 'self_protection', 'defconfig'
358 l += [KconfigCheck('self_protection', 'defconfig', 'BUG', 'y')]
359 l += [KconfigCheck('self_protection', 'defconfig', 'SLUB_DEBUG', 'y')]
360 l += [KconfigCheck('self_protection', 'defconfig', 'THREAD_INFO_IN_TASK', 'y')]
361 gcc_plugins_support_is_set = KconfigCheck('self_protection', 'defconfig', 'GCC_PLUGINS', 'y')
362 l += [gcc_plugins_support_is_set]
363 iommu_support_is_set = KconfigCheck('self_protection', 'defconfig', 'IOMMU_SUPPORT', 'y')
364 l += [iommu_support_is_set] # is needed for mitigating DMA attacks
365 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR', 'y'),
366 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR', 'y'),
367 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_REGULAR', 'y'),
368 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_AUTO', 'y'),
369 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
370 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_STRONG', 'y'),
371 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
372 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_KERNEL_RWX', 'y'),
373 KconfigCheck('self_protection', 'defconfig', 'DEBUG_RODATA', 'y'))] # before v4.11
374 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_MODULE_RWX', 'y'),
375 KconfigCheck('self_protection', 'defconfig', 'DEBUG_SET_MODULE_RONX', 'y'),
376 modules_not_set)] # DEBUG_SET_MODULE_RONX was before v4.11
377 l += [OR(KconfigCheck('self_protection', 'defconfig', 'REFCOUNT_FULL', 'y'),
378 VersionCheck((5, 5)))] # REFCOUNT_FULL is enabled by default since v5.5
379 if arch in ('X86_64', 'ARM64', 'X86_32'):
380 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y')]
381 if arch in ('X86_64', 'ARM64'):
382 l += [KconfigCheck('self_protection', 'defconfig', 'VMAP_STACK', 'y')]
383 if arch in ('X86_64', 'X86_32'):
384 l += [KconfigCheck('self_protection', 'defconfig', 'DEBUG_WX', 'y')]
385 l += [KconfigCheck('self_protection', 'defconfig', 'WERROR', 'y')]
386 l += [KconfigCheck('self_protection', 'defconfig', 'X86_MCE', 'y')]
387 l += [KconfigCheck('self_protection', 'defconfig', 'X86_MCE_INTEL', 'y')]
388 l += [KconfigCheck('self_protection', 'defconfig', 'X86_MCE_AMD', 'y')]
389 l += [KconfigCheck('self_protection', 'defconfig', 'MICROCODE', 'y')] # is needed for mitigating CPU bugs
390 l += [KconfigCheck('self_protection', 'defconfig', 'RETPOLINE', 'y')]
391 l += [KconfigCheck('self_protection', 'defconfig', 'SYN_COOKIES', 'y')] # another reason?
392 l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_SMAP', 'y'),
393 VersionCheck((5, 19)))] # X86_SMAP is enabled by default since v5.19
394 l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_UMIP', 'y'),
395 KconfigCheck('self_protection', 'defconfig', 'X86_INTEL_UMIP', 'y'))]
396 if arch in ('ARM64', 'ARM'):
397 l += [KconfigCheck('self_protection', 'defconfig', 'IOMMU_DEFAULT_DMA_STRICT', 'y')]
398 l += [KconfigCheck('self_protection', 'defconfig', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set')] # true if IOMMU_DEFAULT_DMA_STRICT is set
399 l += [KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_PER_TASK', 'y')]
401 l += [KconfigCheck('self_protection', 'defconfig', 'PAGE_TABLE_ISOLATION', 'y')]
402 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MEMORY', 'y')]
403 l += [AND(KconfigCheck('self_protection', 'defconfig', 'INTEL_IOMMU', 'y'),
404 iommu_support_is_set)]
405 l += [AND(KconfigCheck('self_protection', 'defconfig', 'AMD_IOMMU', 'y'),
406 iommu_support_is_set)]
408 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PAN', 'y')]
409 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_EPAN', 'y')]
410 l += [KconfigCheck('self_protection', 'defconfig', 'UNMAP_KERNEL_AT_EL0', 'y')]
411 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_E0PD', 'y')]
412 l += [KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y')]
413 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PTR_AUTH_KERNEL', 'y')]
414 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_BTI_KERNEL', 'y')]
415 l += [KconfigCheck('self_protection', 'defconfig', 'MITIGATE_SPECTRE_BRANCH_HISTORY', 'y')]
416 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_MTE', 'y')]
417 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MODULE_REGION_FULL', 'y')]
418 l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_EL2_VECTORS', 'y'),
419 AND(KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y'),
420 VersionCheck((5, 9))))] # HARDEN_EL2_VECTORS was included in RANDOMIZE_BASE in v5.9
421 l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y'),
422 VersionCheck((5, 10)))] # HARDEN_BRANCH_PREDICTOR is enabled by default since v5.10
424 l += [KconfigCheck('self_protection', 'defconfig', 'CPU_SW_DOMAIN_PAN', 'y')]
425 l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y')]
426 l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_HISTORY', 'y')]
428 # 'self_protection', 'kspp'
429 l += [KconfigCheck('self_protection', 'kspp', 'BUG_ON_DATA_CORRUPTION', 'y')]
430 l += [KconfigCheck('self_protection', 'kspp', 'SCHED_STACK_END_CHECK', 'y')]
431 l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_HARDENED', 'y')]
432 l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_RANDOM', 'y')]
433 l += [KconfigCheck('self_protection', 'kspp', 'SHUFFLE_PAGE_ALLOCATOR', 'y')]
434 l += [KconfigCheck('self_protection', 'kspp', 'FORTIFY_SOURCE', 'y')]
435 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_LIST', 'y')]
436 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_VIRTUAL', 'y')]
437 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_SG', 'y')]
438 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_CREDENTIALS', 'y')]
439 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_NOTIFIERS', 'y')]
440 l += [KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y')]
441 l += [KconfigCheck('self_protection', 'kspp', 'KFENCE', 'y')]
442 l += [KconfigCheck('self_protection', 'kspp', 'ZERO_CALL_USED_REGS', 'y')]
443 l += [KconfigCheck('self_protection', 'kspp', 'HW_RANDOM_TPM', 'y')]
444 l += [KconfigCheck('self_protection', 'kspp', 'STATIC_USERMODEHELPER', 'y')] # needs userspace support
445 l += [KconfigCheck('self_protection', 'kspp', 'SCHED_CORE', 'y')]
446 randstruct_is_set = OR(KconfigCheck('self_protection', 'kspp', 'RANDSTRUCT_FULL', 'y'),
447 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_RANDSTRUCT', 'y'))
448 l += [randstruct_is_set]
449 l += [AND(KconfigCheck('self_protection', 'kspp', 'RANDSTRUCT_PERFORMANCE', 'is not set'),
450 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_RANDSTRUCT_PERFORMANCE', 'is not set'),
452 hardened_usercopy_is_set = KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y')
453 l += [hardened_usercopy_is_set]
454 l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
455 hardened_usercopy_is_set)]
456 l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_PAGESPAN', 'is not set'),
457 hardened_usercopy_is_set)]
458 l += [AND(KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_LATENT_ENTROPY', 'y'),
459 gcc_plugins_support_is_set)]
460 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG', 'y'),
462 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_ALL', 'y'),
464 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_SHA512', 'y'),
466 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_FORCE', 'y'),
467 modules_not_set)] # refers to LOCKDOWN
468 l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_STACK_ALL_ZERO', 'y'),
469 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STRUCTLEAK_BYREF_ALL', 'y'))]
470 l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
471 KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'))]
472 # CONFIG_INIT_ON_FREE_DEFAULT_ON was added in v5.3.
473 # CONFIG_PAGE_POISONING_ZERO was removed in v5.11.
474 # Starting from v5.11 CONFIG_PAGE_POISONING unconditionally checks
475 # the 0xAA poison pattern on allocation.
476 # That brings higher performance penalty.
477 l += [OR(KconfigCheck('self_protection', 'kspp', 'EFI_DISABLE_PCI_DMA', 'y'),
479 l += [OR(KconfigCheck('self_protection', 'kspp', 'RESET_ATTACK_MITIGATION', 'y'),
480 efi_not_set)] # needs userspace support (systemd)
481 ubsan_bounds_is_set = KconfigCheck('self_protection', 'kspp', 'UBSAN_BOUNDS', 'y')
482 l += [ubsan_bounds_is_set]
483 l += [OR(KconfigCheck('self_protection', 'kspp', 'UBSAN_LOCAL_BOUNDS', 'y'),
484 AND(ubsan_bounds_is_set,
486 l += [AND(KconfigCheck('self_protection', 'kspp', 'UBSAN_TRAP', 'y'),
488 KconfigCheck('self_protection', 'kspp', 'UBSAN_SHIFT', 'is not set'),
489 KconfigCheck('self_protection', 'kspp', 'UBSAN_DIV_ZERO', 'is not set'),
490 KconfigCheck('self_protection', 'kspp', 'UBSAN_UNREACHABLE', 'is not set'),
491 KconfigCheck('self_protection', 'kspp', 'UBSAN_BOOL', 'is not set'),
492 KconfigCheck('self_protection', 'kspp', 'UBSAN_ENUM', 'is not set'),
493 KconfigCheck('self_protection', 'kspp', 'UBSAN_ALIGNMENT', 'is not set'))] # only array index bounds checking with traps
494 if arch in ('X86_64', 'ARM64', 'X86_32'):
495 l += [AND(KconfigCheck('self_protection', 'kspp', 'UBSAN_SANITIZE_ALL', 'y'),
496 ubsan_bounds_is_set)] # ARCH_HAS_UBSAN_SANITIZE_ALL is not enabled for ARM
497 stackleak_is_set = KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STACKLEAK', 'y')
498 l += [AND(stackleak_is_set, gcc_plugins_support_is_set)]
499 l += [AND(KconfigCheck('self_protection', 'kspp', 'STACKLEAK_METRICS', 'is not set'),
501 gcc_plugins_support_is_set)]
502 l += [AND(KconfigCheck('self_protection', 'kspp', 'STACKLEAK_RUNTIME_DISABLE', 'is not set'),
504 gcc_plugins_support_is_set)]
505 l += [KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y')]
506 if arch in ('X86_64', 'ARM64'):
507 cfi_clang_is_set = KconfigCheck('self_protection', 'kspp', 'CFI_CLANG', 'y')
508 l += [cfi_clang_is_set]
509 l += [AND(KconfigCheck('self_protection', 'kspp', 'CFI_PERMISSIVE', 'is not set'),
511 if arch in ('X86_64', 'X86_32'):
512 l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '65536')]
513 l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y')]
514 l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set')] # true if IOMMU_DEFAULT_DMA_STRICT is set
515 l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU_DEFAULT_ON', 'y'),
516 iommu_support_is_set)]
517 if arch in ('ARM64', 'ARM'):
518 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_WX', 'y')]
519 l += [KconfigCheck('self_protection', 'kspp', 'WERROR', 'y')]
520 l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '32768')]
521 l += [KconfigCheck('self_protection', 'kspp', 'SYN_COOKIES', 'y')] # another reason?
523 l += [KconfigCheck('self_protection', 'kspp', 'SLS', 'y')] # vs CVE-2021-26341 in Straight-Line-Speculation
524 l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU_SVM', 'y'),
525 iommu_support_is_set)]
526 l += [AND(KconfigCheck('self_protection', 'kspp', 'AMD_IOMMU_V2', 'y'),
527 iommu_support_is_set)]
529 l += [KconfigCheck('self_protection', 'kspp', 'ARM64_SW_TTBR0_PAN', 'y')]
530 l += [KconfigCheck('self_protection', 'kspp', 'SHADOW_CALL_STACK', 'y')]
531 l += [KconfigCheck('self_protection', 'kspp', 'KASAN_HW_TAGS', 'y')]
533 l += [KconfigCheck('self_protection', 'kspp', 'PAGE_TABLE_ISOLATION', 'y')]
534 l += [KconfigCheck('self_protection', 'kspp', 'HIGHMEM64G', 'y')]
535 l += [KconfigCheck('self_protection', 'kspp', 'X86_PAE', 'y')]
536 l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU', 'y'),
537 iommu_support_is_set)]
539 # 'self_protection', 'clipos'
540 l += [KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set')]
543 if arch in ('X86_64', 'ARM64', 'X86_32'):
544 l += [KconfigCheck('security_policy', 'defconfig', 'SECURITY', 'y')] # and choose your favourite LSM
546 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY', 'y')] # and choose your favourite LSM
547 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_YAMA', 'y')]
548 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LANDLOCK', 'y')]
549 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_DISABLE', 'is not set')]
550 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_BOOTPARAM', 'is not set')]
551 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_DEVELOP', 'is not set')]
552 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LOCKDOWN_LSM', 'y')]
553 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LOCKDOWN_LSM_EARLY', 'y')]
554 l += [KconfigCheck('security_policy', 'kspp', 'LOCK_DOWN_KERNEL_FORCE_CONFIDENTIALITY', 'y')]
555 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_WRITABLE_HOOKS', 'is not set')] # refers to SECURITY_SELINUX_DISABLE
557 # 'cut_attack_surface', 'defconfig'
558 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP', 'y')]
559 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP_FILTER', 'y')]
560 l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'BPF_UNPRIV_DEFAULT_OFF', 'y'),
561 bpf_syscall_not_set)] # see unprivileged_bpf_disabled
562 if arch in ('X86_64', 'ARM64', 'X86_32'):
563 l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'STRICT_DEVMEM', 'y'),
564 devmem_not_set)] # refers to LOCKDOWN
565 if arch in ('X86_64', 'X86_32'):
566 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'X86_INTEL_TSX_MODE_OFF', 'y')] # tsx=off
568 # 'cut_attack_surface', 'kspp'
569 l += [KconfigCheck('cut_attack_surface', 'kspp', 'SECURITY_DMESG_RESTRICT', 'y')]
570 l += [KconfigCheck('cut_attack_surface', 'kspp', 'ACPI_CUSTOM_METHOD', 'is not set')] # refers to LOCKDOWN
571 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_BRK', 'is not set')]
572 l += [KconfigCheck('cut_attack_surface', 'kspp', 'DEVKMEM', 'is not set')] # refers to LOCKDOWN
573 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_VDSO', 'is not set')]
574 l += [KconfigCheck('cut_attack_surface', 'kspp', 'BINFMT_MISC', 'is not set')]
575 l += [KconfigCheck('cut_attack_surface', 'kspp', 'INET_DIAG', 'is not set')]
576 l += [KconfigCheck('cut_attack_surface', 'kspp', 'KEXEC', 'is not set')] # refers to LOCKDOWN
577 l += [KconfigCheck('cut_attack_surface', 'kspp', 'PROC_KCORE', 'is not set')] # refers to LOCKDOWN
578 l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_PTYS', 'is not set')]
579 l += [KconfigCheck('cut_attack_surface', 'kspp', 'HIBERNATION', 'is not set')] # refers to LOCKDOWN
580 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT', 'is not set')]
581 l += [KconfigCheck('cut_attack_surface', 'kspp', 'IA32_EMULATION', 'is not set')]
582 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_X32', 'is not set')]
583 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_X32_ABI', 'is not set')]
584 l += [KconfigCheck('cut_attack_surface', 'kspp', 'MODIFY_LDT_SYSCALL', 'is not set')]
585 l += [KconfigCheck('cut_attack_surface', 'kspp', 'OABI_COMPAT', 'is not set')]
586 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_MSR', 'is not set')] # refers to LOCKDOWN
587 l += [modules_not_set]
588 l += [devmem_not_set]
589 l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'IO_STRICT_DEVMEM', 'y'),
590 devmem_not_set)] # refers to LOCKDOWN
591 l += [AND(KconfigCheck('cut_attack_surface', 'kspp', 'LDISC_AUTOLOAD', 'is not set'),
592 KconfigCheck('cut_attack_surface', 'kspp', 'LDISC_AUTOLOAD', 'is present'))]
594 l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y')] # 'vsyscall=none'
596 l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'STRICT_DEVMEM', 'y'),
597 devmem_not_set)] # refers to LOCKDOWN
599 # 'cut_attack_surface', 'grsec'
600 l += [KconfigCheck('cut_attack_surface', 'grsec', 'ZSMALLOC_STAT', 'is not set')]
601 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PAGE_OWNER', 'is not set')]
602 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_KMEMLEAK', 'is not set')]
603 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BINFMT_AOUT', 'is not set')]
604 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KPROBE_EVENTS', 'is not set')]
605 l += [KconfigCheck('cut_attack_surface', 'grsec', 'UPROBE_EVENTS', 'is not set')]
606 l += [KconfigCheck('cut_attack_surface', 'grsec', 'GENERIC_TRACER', 'is not set')] # refers to LOCKDOWN
607 l += [KconfigCheck('cut_attack_surface', 'grsec', 'FUNCTION_TRACER', 'is not set')]
608 l += [KconfigCheck('cut_attack_surface', 'grsec', 'STACK_TRACER', 'is not set')]
609 l += [KconfigCheck('cut_attack_surface', 'grsec', 'HIST_TRIGGERS', 'is not set')]
610 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BLK_DEV_IO_TRACE', 'is not set')]
611 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_VMCORE', 'is not set')]
612 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_PAGE_MONITOR', 'is not set')]
613 l += [KconfigCheck('cut_attack_surface', 'grsec', 'USELIB', 'is not set')]
614 l += [KconfigCheck('cut_attack_surface', 'grsec', 'CHECKPOINT_RESTORE', 'is not set')]
615 l += [KconfigCheck('cut_attack_surface', 'grsec', 'USERFAULTFD', 'is not set')]
616 l += [KconfigCheck('cut_attack_surface', 'grsec', 'HWPOISON_INJECT', 'is not set')]
617 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MEM_SOFT_DIRTY', 'is not set')]
618 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEVPORT', 'is not set')] # refers to LOCKDOWN
619 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set')] # refers to LOCKDOWN
620 l += [KconfigCheck('cut_attack_surface', 'grsec', 'NOTIFIER_ERROR_INJECTION', 'is not set')]
621 l += [KconfigCheck('cut_attack_surface', 'grsec', 'FAIL_FUTEX', 'is not set')]
622 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PUNIT_ATOM_DEBUG', 'is not set')]
623 l += [KconfigCheck('cut_attack_surface', 'grsec', 'ACPI_CONFIGFS', 'is not set')]
624 l += [KconfigCheck('cut_attack_surface', 'grsec', 'EDAC_DEBUG', 'is not set')]
625 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DRM_I915_DEBUG', 'is not set')]
626 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BCACHE_CLOSURES_DEBUG', 'is not set')]
627 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DVB_C8SECTPFE', 'is not set')]
628 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_SLRAM', 'is not set')]
629 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_PHRAM', 'is not set')]
630 l += [KconfigCheck('cut_attack_surface', 'grsec', 'IO_URING', 'is not set')]
631 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCMP', 'is not set')]
632 l += [KconfigCheck('cut_attack_surface', 'grsec', 'RSEQ', 'is not set')]
633 l += [KconfigCheck('cut_attack_surface', 'grsec', 'LATENCYTOP', 'is not set')]
634 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCOV', 'is not set')]
635 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROVIDE_OHCI1394_DMA_INIT', 'is not set')]
636 l += [KconfigCheck('cut_attack_surface', 'grsec', 'SUNRPC_DEBUG', 'is not set')]
637 l += [AND(KconfigCheck('cut_attack_surface', 'grsec', 'PTDUMP_DEBUGFS', 'is not set'),
638 KconfigCheck('cut_attack_surface', 'grsec', 'X86_PTDUMP', 'is not set'))]
640 # 'cut_attack_surface', 'maintainer'
641 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'DRM_LEGACY', 'is not set')] # recommended by Daniel Vetter in /issues/38
642 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'FB', 'is not set')] # recommended by Daniel Vetter in /issues/38
643 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'VT', 'is not set')] # recommended by Daniel Vetter in /issues/38
644 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD', 'is not set')] # recommended by Denis Efremov in /pull/54
645 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD_RAWCMD', 'is not set')] # recommended by Denis Efremov in /pull/62
647 # 'cut_attack_surface', 'clipos'
648 l += [KconfigCheck('cut_attack_surface', 'clipos', 'STAGING', 'is not set')]
649 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KSM', 'is not set')] # to prevent FLUSH+RELOAD attack
650 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KALLSYMS', 'is not set')]
651 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_VSYSCALL_EMULATION', 'is not set')]
652 l += [KconfigCheck('cut_attack_surface', 'clipos', 'MAGIC_SYSRQ', 'is not set')]
653 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KEXEC_FILE', 'is not set')] # refers to LOCKDOWN (permissive)
654 l += [KconfigCheck('cut_attack_surface', 'clipos', 'USER_NS', 'is not set')] # user.max_user_namespaces=0
655 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_CPUID', 'is not set')]
656 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_IOPL_IOPERM', 'is not set')] # refers to LOCKDOWN
657 l += [KconfigCheck('cut_attack_surface', 'clipos', 'ACPI_TABLE_UPGRADE', 'is not set')] # refers to LOCKDOWN
658 l += [KconfigCheck('cut_attack_surface', 'clipos', 'EFI_CUSTOM_SSDT_OVERLAYS', 'is not set')]
659 l += [KconfigCheck('cut_attack_surface', 'clipos', 'COREDUMP', 'is not set')] # cut userspace attack surface
660 # l += [KconfigCheck('cut_attack_surface', 'clipos', 'IKCONFIG', 'is not set')] # no, IKCONFIG is needed for this check :)
662 # 'cut_attack_surface', 'lockdown'
663 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'EFI_TEST', 'is not set')] # refers to LOCKDOWN
664 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'MMIOTRACE_TEST', 'is not set')] # refers to LOCKDOWN
665 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'KPROBES', 'is not set')] # refers to LOCKDOWN
666 l += [bpf_syscall_not_set] # refers to LOCKDOWN
668 # 'cut_attack_surface', 'my'
669 l += [KconfigCheck('cut_attack_surface', 'my', 'MMIOTRACE', 'is not set')] # refers to LOCKDOWN (permissive)
670 l += [KconfigCheck('cut_attack_surface', 'my', 'LIVEPATCH', 'is not set')]
671 l += [KconfigCheck('cut_attack_surface', 'my', 'IP_DCCP', 'is not set')]
672 l += [KconfigCheck('cut_attack_surface', 'my', 'IP_SCTP', 'is not set')]
673 l += [KconfigCheck('cut_attack_surface', 'my', 'FTRACE', 'is not set')] # refers to LOCKDOWN
674 l += [KconfigCheck('cut_attack_surface', 'my', 'VIDEO_VIVID', 'is not set')]
675 l += [KconfigCheck('cut_attack_surface', 'my', 'INPUT_EVBUG', 'is not set')] # Can be used as a keylogger
676 l += [KconfigCheck('cut_attack_surface', 'my', 'KGDB', 'is not set')]
677 l += [OR(KconfigCheck('cut_attack_surface', 'my', 'TRIM_UNUSED_KSYMS', 'y'),
681 if arch in ('X86_64', 'ARM64', 'X86_32'):
682 l += [KconfigCheck('harden_userspace', 'defconfig', 'INTEGRITY', 'y')]
684 l += [KconfigCheck('harden_userspace', 'my', 'INTEGRITY', 'y')]
686 l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_PTR_AUTH', 'y')]
687 l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_BTI', 'y')]
688 if arch in ('ARM', 'X86_32'):
689 l += [KconfigCheck('harden_userspace', 'defconfig', 'VMSPLIT_3G', 'y')]
690 if arch in ('X86_64', 'ARM64'):
691 l += [KconfigCheck('harden_userspace', 'clipos', 'ARCH_MMAP_RND_BITS', '32')]
692 if arch in ('X86_32', 'ARM'):
693 l += [KconfigCheck('harden_userspace', 'my', 'ARCH_MMAP_RND_BITS', '16')]
696 def add_cmdline_checks(l, arch):
697 # Calling the CmdlineCheck class constructor:
698 # CmdlineCheck(reason, decision, name, expected)
700 # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
701 # when the tool doesn't check the cmdline.
703 # [!] Make sure that values of the options in CmdlineChecks need normalization.
704 # For more info see normalize_cmdline_options().
706 # A common pattern for checking the 'param_x' cmdline parameter
707 # that __overrides__ the 'PARAM_X_DEFAULT' kconfig option:
708 # l += [OR(CmdlineCheck(reason, decision, 'param_x', '1'),
709 # AND(KconfigCheck(reason, decision, 'PARAM_X_DEFAULT_ON', 'y'),
710 # CmdlineCheck(reason, decision, 'param_x, 'is not set')))]
712 # Here we don't check the kconfig options or minimal kernel version
713 # required for the cmdline parameters. That would make the checks
714 # very complex and not give a 100% guarantee anyway.
716 # 'self_protection', 'defconfig'
717 l += [CmdlineCheck('self_protection', 'defconfig', 'nosmep', 'is not set')]
718 l += [CmdlineCheck('self_protection', 'defconfig', 'nosmap', 'is not set')]
719 l += [CmdlineCheck('self_protection', 'defconfig', 'nokaslr', 'is not set')]
720 l += [CmdlineCheck('self_protection', 'defconfig', 'nopti', 'is not set')]
721 l += [CmdlineCheck('self_protection', 'defconfig', 'nospectre_v1', 'is not set')]
722 l += [CmdlineCheck('self_protection', 'defconfig', 'nospectre_v2', 'is not set')]
723 l += [CmdlineCheck('self_protection', 'defconfig', 'nospectre_bhb', 'is not set')]
724 l += [CmdlineCheck('self_protection', 'defconfig', 'nospec_store_bypass_disable', 'is not set')]
725 l += [CmdlineCheck('self_protection', 'defconfig', 'arm64.nobti', 'is not set')]
726 l += [CmdlineCheck('self_protection', 'defconfig', 'arm64.nopauth', 'is not set')]
727 l += [CmdlineCheck('self_protection', 'defconfig', 'arm64.nomte', 'is not set')]
728 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'mitigations', 'is not off'),
729 CmdlineCheck('self_protection', 'defconfig', 'mitigations', 'is not set'))]
730 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'spectre_v2', 'is not off'),
731 CmdlineCheck('self_protection', 'defconfig', 'spectre_v2', 'is not set'))]
732 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'spectre_v2_user', 'is not off'),
733 CmdlineCheck('self_protection', 'defconfig', 'spectre_v2_user', 'is not set'))]
734 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'spec_store_bypass_disable', 'is not off'),
735 CmdlineCheck('self_protection', 'defconfig', 'spec_store_bypass_disable', 'is not set'))]
736 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'l1tf', 'is not off'),
737 CmdlineCheck('self_protection', 'defconfig', 'l1tf', 'is not set'))]
738 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'mds', 'is not off'),
739 CmdlineCheck('self_protection', 'defconfig', 'mds', 'is not set'))]
740 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'tsx_async_abort', 'is not off'),
741 CmdlineCheck('self_protection', 'defconfig', 'tsx_async_abort', 'is not set'))]
742 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'srbds', 'is not off'),
743 CmdlineCheck('self_protection', 'defconfig', 'srbds', 'is not set'))]
744 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'mmio_stale_data', 'is not off'),
745 CmdlineCheck('self_protection', 'defconfig', 'mmio_stale_data', 'is not set'))]
746 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'retbleed', 'is not off'),
747 CmdlineCheck('self_protection', 'defconfig', 'retbleed', 'is not set'))]
748 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'kpti', 'is not off'),
749 CmdlineCheck('self_protection', 'defconfig', 'kpti', 'is not set'))]
751 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'ssbd', 'kernel'),
752 CmdlineCheck('self_protection', 'my', 'ssbd', 'force-on'),
753 CmdlineCheck('self_protection', 'defconfig', 'ssbd', 'is not set'))]
754 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', 'full'),
755 AND(KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y'),
756 CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set')))]
758 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', '1'),
759 CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set'))]
761 # 'self_protection', 'kspp'
762 l += [CmdlineCheck('self_protection', 'kspp', 'nosmt', 'is present')]
763 l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', '1'),
764 AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y'),
765 CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', 'is not set')))]
766 l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_free', '1'),
767 AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
768 CmdlineCheck('self_protection', 'kspp', 'init_on_free', 'is not set')),
769 AND(CmdlineCheck('self_protection', 'kspp', 'page_poison', '1'),
770 KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'),
771 CmdlineCheck('self_protection', 'kspp', 'slub_debug', 'P')))]
772 l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_nomerge', 'is present'),
773 AND(KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set'),
774 CmdlineCheck('self_protection', 'kspp', 'slab_merge', 'is not set')))]
775 l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.strict', '1'),
776 AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y'),
777 CmdlineCheck('self_protection', 'kspp', 'iommu.strict', 'is not set')))]
778 l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', '0'),
779 AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set'),
780 CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', 'is not set')))]
781 # The cmdline checks compatible with the kconfig recommendations of the KSPP project...
782 l += [OR(CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', '1'),
783 AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y'),
784 CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', 'is not set')))]
785 l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', '0'),
786 AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
787 CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', 'is not set')))]
789 if arch in ('X86_64', 'ARM64', 'X86_32'):
790 l += [OR(CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', '1'),
791 AND(KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y'),
792 CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', 'is not set')))]
793 if arch in ('X86_64', 'X86_32'):
794 l += [AND(CmdlineCheck('self_protection', 'kspp', 'pti', 'on'),
795 CmdlineCheck('self_protection', 'defconfig', 'nopti', 'is not set'))]
797 # 'self_protection', 'clipos'
798 l += [CmdlineCheck('self_protection', 'clipos', 'page_alloc.shuffle', '1')]
800 # 'cut_attack_surface', 'defconfig'
801 if arch in ('X86_64', 'X86_32'):
802 l += [OR(CmdlineCheck('cut_attack_surface', 'defconfig', 'tsx', 'off'),
803 AND(KconfigCheck('cut_attack_surface', 'defconfig', 'X86_INTEL_TSX_MODE_OFF', 'y'),
804 CmdlineCheck('cut_attack_surface', 'defconfig', 'tsx', 'is not set')))]
806 # 'cut_attack_surface', 'kspp'
808 l += [OR(CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'none'),
809 AND(KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y'),
810 CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'is not set')))]
812 # 'cut_attack_surface', 'grsec'
813 # The cmdline checks compatible with the kconfig options disabled by grsecurity...
814 l += [OR(CmdlineCheck('cut_attack_surface', 'grsec', 'debugfs', 'off'),
815 KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set'))] # ... the end
817 # 'cut_attack_surface', 'my'
818 l += [CmdlineCheck('cut_attack_surface', 'my', 'sysrq_always_enabled', 'is not set')]
820 def print_unknown_options(checklist, parsed_options):
824 if o1.type != 'complex':
825 known_options.append(o1.name)
828 if o2.type != 'complex':
829 if hasattr(o2, 'name'):
830 known_options.append(o2.name)
833 assert(o3.type != 'complex'), \
834 'unexpected ComplexOptCheck inside {}'.format(o2.name)
835 if hasattr(o3, 'name'):
836 known_options.append(o3.name)
838 for option, value in parsed_options.items():
839 if option not in known_options:
840 print('[?] No check for option {} ({})'.format(option, value))
843 def print_checklist(mode, checklist, with_results):
847 output.append(o.json_dump(with_results))
848 print(json.dumps(output))
855 print('=' * sep_line_len)
856 print('{:^40}|{:^7}|{:^12}|{:^10}|{:^18}'.format('option name', 'type', 'desired val', 'decision', 'reason'), end='')
858 print('| {}'.format('check result'), end='')
860 print('=' * sep_line_len)
863 for opt in checklist:
865 if mode == 'show_ok':
866 if not opt.result.startswith('OK'):
868 if mode == 'show_fail':
869 if not opt.result.startswith('FAIL'):
871 opt.table_print(mode, with_results)
873 if mode == 'verbose':
874 print('-' * sep_line_len)
879 fail_count = len(list(filter(lambda opt: opt.result.startswith('FAIL'), checklist)))
881 ok_count = len(list(filter(lambda opt: opt.result.startswith('OK'), checklist)))
883 if mode == 'show_ok':
884 fail_suppressed = ' (suppressed in output)'
885 if mode == 'show_fail':
886 ok_suppressed = ' (suppressed in output)'
888 print('[+] Config check is finished: \'OK\' - {}{} / \'FAIL\' - {}{}'.format(ok_count, ok_suppressed, fail_count, fail_suppressed))
891 def populate_simple_opt_with_data(opt, data, data_type):
892 assert(opt.type != 'complex'), \
893 'unexpected ComplexOptCheck "{}"'.format(opt.name)
894 assert(opt.type in SIMPLE_OPTION_TYPES), \
895 'invalid opt type "{}"'.format(opt.type)
896 assert(data_type in SIMPLE_OPTION_TYPES), \
897 'invalid data type "{}"'.format(data_type)
899 if data_type != opt.type:
902 if data_type in ('kconfig', 'cmdline'):
903 opt.state = data.get(opt.name, None)
905 assert(data_type == 'version'), \
906 'unexpected data type "{}"'.format(data_type)
910 def populate_opt_with_data(opt, data, data_type):
911 if opt.type == 'complex':
913 if o.type == 'complex':
914 # Recursion for nested ComplexOptCheck objects
915 populate_opt_with_data(o, data, data_type)
917 populate_simple_opt_with_data(o, data, data_type)
919 assert(opt.type in ('kconfig', 'cmdline')), \
920 'bad type "{}" for a simple check'.format(opt.type)
921 populate_simple_opt_with_data(opt, data, data_type)
924 def populate_with_data(checklist, data, data_type):
925 for opt in checklist:
926 populate_opt_with_data(opt, data, data_type)
929 def perform_checks(checklist):
930 for opt in checklist:
934 def parse_kconfig_file(parsed_options, fname):
935 with open(fname, 'r') as f:
936 opt_is_on = re.compile("CONFIG_[a-zA-Z0-9_]*=[a-zA-Z0-9_\"]*")
937 opt_is_off = re.compile("# CONFIG_[a-zA-Z0-9_]* is not set")
939 for line in f.readlines():
944 if opt_is_on.match(line):
945 option, value = line.split('=', 1)
946 if value == 'is not set':
947 sys.exit('[!] ERROR: bad enabled kconfig option "{}"'.format(line))
948 elif opt_is_off.match(line):
949 option, value = line[2:].split(' ', 1)
950 if value != 'is not set':
951 sys.exit('[!] ERROR: bad disabled kconfig option "{}"'.format(line))
953 if option in parsed_options:
954 sys.exit('[!] ERROR: kconfig option "{}" exists multiple times'.format(line))
957 parsed_options[option] = value
960 def normalize_cmdline_options(option, value):
961 # Don't normalize the cmdline option values if
962 # the Linux kernel doesn't use kstrtobool() for them
963 if option == 'debugfs':
964 # See debugfs_kernel() in fs/debugfs/inode.c
966 if option == 'mitigations':
967 # See mitigations_parse_cmdline() in kernel/cpu.c
970 # See pti_check_boottime_disable() in arch/x86/mm/pti.c
972 if option == 'spectre_v2':
973 # See spectre_v2_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
975 if option == 'spectre_v2_user':
976 # See spectre_v2_parse_user_cmdline() in arch/x86/kernel/cpu/bugs.c
978 if option == 'spec_store_bypass_disable':
979 # See ssb_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
982 # See l1tf_cmdline() in arch/x86/kernel/cpu/bugs.c
985 # See mds_cmdline() in arch/x86/kernel/cpu/bugs.c
987 if option == 'tsx_async_abort':
988 # See tsx_async_abort_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
990 if option == 'srbds':
991 # See srbds_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
993 if option == 'mmio_stale_data':
994 # See mmio_stale_data_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
996 if option == 'retbleed':
997 # See retbleed_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
1000 # See tsx_init() in arch/x86/kernel/cpu/tsx.c
1003 # Implement a limited part of the kstrtobool() logic
1004 if value in ('1', 'on', 'On', 'ON', 'y', 'Y', 'yes', 'Yes', 'YES'):
1006 if value in ('0', 'off', 'Off', 'OFF', 'n', 'N', 'no', 'No', 'NO'):
1009 # Preserve unique values
1013 def parse_cmdline_file(parsed_options, fname):
1014 with open(fname, 'r') as f:
1020 sys.exit('[!] ERROR: more than one line in "{}"'.format(fname))
1024 name, value = opt.split('=', 1)
1027 value = '' # '' is not None
1028 value = normalize_cmdline_options(name, value)
1029 parsed_options[name] = value
1034 # * verbose mode for
1035 # - reporting about unknown kernel options in the kconfig
1036 # - verbose printing of ComplexOptCheck items
1037 # * json mode for printing the results in JSON format
1038 report_modes = ['verbose', 'json', 'show_ok', 'show_fail']
1039 supported_archs = ['X86_64', 'X86_32', 'ARM64', 'ARM']
1040 parser = ArgumentParser(prog='kconfig-hardened-check',
1041 description='A tool for checking the security hardening options of the Linux kernel')
1042 parser.add_argument('--version', action='version', version='%(prog)s ' + __version__)
1043 parser.add_argument('-p', '--print', choices=supported_archs,
1044 help='print security hardening preferences for the selected architecture')
1045 parser.add_argument('-c', '--config',
1046 help='check the kernel kconfig file against these preferences')
1047 parser.add_argument('-l', '--cmdline',
1048 help='check the kernel cmdline file against these preferences')
1049 parser.add_argument('-m', '--mode', choices=report_modes,
1050 help='choose the report mode')
1051 args = parser.parse_args()
1057 print('[+] Special report mode: {}'.format(mode))
1059 config_checklist = []
1063 sys.exit('[!] ERROR: --config and --print can\'t be used together')
1066 print('[+] Kconfig file to check: {}'.format(args.config))
1068 print('[+] Kernel cmdline file to check: {}'.format(args.cmdline))
1070 arch, msg = detect_arch(args.config, supported_archs)
1072 sys.exit('[!] ERROR: {}'.format(msg))
1074 print('[+] Detected architecture: {}'.format(arch))
1076 kernel_version, msg = detect_kernel_version(args.config)
1077 if not kernel_version:
1078 sys.exit('[!] ERROR: {}'.format(msg))
1080 print('[+] Detected kernel version: {}.{}'.format(kernel_version[0], kernel_version[1]))
1082 compiler, msg = detect_compiler(args.config)
1085 print('[+] Detected compiler: {}'.format(compiler))
1087 print('[-] Can\'t detect the compiler: {}'.format(msg))
1089 # add relevant kconfig checks to the checklist
1090 add_kconfig_checks(config_checklist, arch)
1093 # add relevant cmdline checks to the checklist
1094 add_cmdline_checks(config_checklist, arch)
1096 # populate the checklist with the parsed kconfig data
1097 parsed_kconfig_options = OrderedDict()
1098 parse_kconfig_file(parsed_kconfig_options, args.config)
1099 populate_with_data(config_checklist, parsed_kconfig_options, 'kconfig')
1100 populate_with_data(config_checklist, kernel_version, 'version')
1103 # populate the checklist with the parsed kconfig data
1104 parsed_cmdline_options = OrderedDict()
1105 parse_cmdline_file(parsed_cmdline_options, args.cmdline)
1106 populate_with_data(config_checklist, parsed_cmdline_options, 'cmdline')
1108 # now everything is ready for performing the checks
1109 perform_checks(config_checklist)
1111 # finally print the results
1112 if mode == 'verbose':
1113 print_unknown_options(config_checklist, parsed_kconfig_options)
1114 print_checklist(mode, config_checklist, True)
1118 sys.exit('[!] ERROR: checking cmdline doesn\'t work without checking kconfig')
1121 if mode in ('show_ok', 'show_fail'):
1122 sys.exit('[!] ERROR: wrong mode "{}" for --print'.format(mode))
1124 add_kconfig_checks(config_checklist, arch)
1125 add_cmdline_checks(config_checklist, arch)
1127 print('[+] Printing kernel security hardening preferences for {}...'.format(arch))
1128 print_checklist(mode, config_checklist, False)