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 Hardening command line parameters:
14 # iommu=force (does it help against DMA attacks?)
16 # Mitigations of CPU vulnerabilities:
19 # l1d_flush=on (a part of the l1tf option)
24 # Hardware tag-based KASAN with arm64 Memory Tagging Extension (MTE):
26 # kasan.stacktrace=off
29 # N.B. Hardening sysctls:
30 # kernel.kptr_restrict=2 (or 1?)
31 # kernel.dmesg_restrict=1 (also see the kconfig option)
32 # kernel.perf_event_paranoid=3
33 # kernel.kexec_load_disabled=1
34 # kernel.yama.ptrace_scope=3
35 # user.max_user_namespaces=0
36 # what about bpf_jit_enable?
37 # kernel.unprivileged_bpf_disabled=1
38 # net.core.bpf_jit_harden=2
39 # vm.unprivileged_userfaultfd=0
40 # (at first, it disabled unprivileged userfaultfd,
41 # and since v5.11 it enables unprivileged userfaultfd for user-mode only)
42 # vm.mmap_min_addr has a good value
43 # dev.tty.ldisc_autoload=0
44 # fs.protected_symlinks=1
45 # fs.protected_hardlinks=1
46 # fs.protected_fifos=2
47 # fs.protected_regular=2
49 # kernel.modules_disabled=1
50 # kernel.randomize_va_space = 2
53 # pylint: disable=missing-module-docstring,missing-class-docstring,missing-function-docstring
54 # pylint: disable=line-too-long,invalid-name,too-many-branches,too-many-statements
58 from argparse import ArgumentParser
59 from collections import OrderedDict
62 from .__about__ import __version__
64 SIMPLE_OPTION_TYPES = ('kconfig', 'version', 'cmdline')
67 def __init__(self, reason, decision, name, expected):
68 assert(name and name == name.strip() and len(name.split()) == 1), \
69 'invalid name "{}" for {}'.format(name, self.__class__.__name__)
72 assert(decision and decision == decision.strip() and len(decision.split()) == 1), \
73 'invalid decision "{}" for "{}" check'.format(decision, name)
74 self.decision = decision
76 assert(reason and reason == reason.strip() and len(reason.split()) == 1), \
77 'invalid reason "{}" for "{}" check'.format(reason, name)
80 assert(expected and expected == expected.strip()), \
81 'invalid expected value "{}" for "{}" check (1)'.format(expected, name)
82 val_len = len(expected.split())
84 assert(expected == 'is not set' or expected == 'is not off'), \
85 'invalid expected value "{}" for "{}" check (2)'.format(expected, name)
87 assert(expected == 'is present'), \
88 'invalid expected value "{}" for "{}" check (3)'.format(expected, name)
90 assert(val_len == 1), \
91 'invalid expected value "{}" for "{}" check (4)'.format(expected, name)
92 self.expected = expected
102 # handle the 'is present' check
103 if self.expected == 'is present':
104 if self.state is None:
105 self.result = 'FAIL: is not present'
107 self.result = 'OK: is present'
110 # handle the 'is not off' option check
111 if self.expected == 'is not off':
112 if self.state == 'off':
113 self.result = 'FAIL: is off'
114 elif self.state is None:
115 self.result = 'FAIL: is off, not found'
117 self.result = 'OK: is not off, "' + self.state + '"'
120 # handle the option value check
121 if self.expected == self.state:
123 elif self.state is None:
124 if self.expected == 'is not set':
125 self.result = 'OK: is not found'
127 self.result = 'FAIL: is not found'
129 self.result = 'FAIL: "' + self.state + '"'
131 def table_print(self, _mode, with_results):
132 print('{:<40}|{:^7}|{:^12}|{:^10}|{:^18}'.format(self.name, self.type, self.expected, self.decision, self.reason), end='')
134 print('| {}'.format(self.result), end='')
136 def json_dump(self, with_results):
137 dump = [self.name, self.type, self.expected, self.decision, self.reason]
139 dump.append(self.result)
143 class KconfigCheck(OptCheck):
144 def __init__(self, *args, **kwargs):
145 super().__init__(*args, **kwargs)
146 self.name = 'CONFIG_' + self.name
153 class CmdlineCheck(OptCheck):
160 def __init__(self, ver_expected):
161 assert(ver_expected and isinstance(ver_expected, tuple) and len(ver_expected) == 2), \
162 'invalid version "{}" for VersionCheck'.format(ver_expected)
163 self.ver_expected = ver_expected
172 if self.ver[0] > self.ver_expected[0]:
173 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
175 if self.ver[0] < self.ver_expected[0]:
176 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
178 if self.ver[1] >= self.ver_expected[1]:
179 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
181 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
183 def table_print(self, _mode, with_results):
184 ver_req = 'kernel version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
185 print('{:<91}'.format(ver_req), end='')
187 print('| {}'.format(self.result), end='')
190 class ComplexOptCheck:
191 def __init__(self, *opts):
194 'empty {} check'.format(self.__class__.__name__)
195 assert(len(self.opts) != 1), \
196 'useless {} check: {}'.format(self.__class__.__name__, opts)
197 assert(isinstance(opts[0], (KconfigCheck, CmdlineCheck))), \
198 'invalid {} check: {}'.format(self.__class__.__name__, opts)
207 return self.opts[0].name
211 return self.opts[0].expected
213 def table_print(self, mode, with_results):
214 if mode == 'verbose':
215 print(' {:87}'.format('<<< ' + self.__class__.__name__ + ' >>>'), end='')
217 print('| {}'.format(self.result), end='')
220 o.table_print(mode, with_results)
223 o.table_print(mode, False)
225 print('| {}'.format(self.result), end='')
227 def json_dump(self, with_results):
228 dump = self.opts[0].json_dump(False)
230 dump.append(self.result)
234 class OR(ComplexOptCheck):
235 # self.opts[0] is the option that this OR-check is about.
237 # OR(<X_is_hardened>, <X_is_disabled>)
238 # OR(<X_is_hardened>, <old_X_is_hardened>)
240 for i, opt in enumerate(self.opts):
242 if opt.result.startswith('OK'):
243 self.result = opt.result
244 # Add more info for additional checks:
246 if opt.result == 'OK':
247 self.result = 'OK: {} is "{}"'.format(opt.name, opt.expected)
248 elif opt.result == 'OK: is not found':
249 self.result = 'OK: {} is not found'.format(opt.name)
250 elif opt.result == 'OK: is present':
251 self.result = 'OK: {} is present'.format(opt.name)
252 elif opt.result.startswith('OK: is not off'):
253 self.result = 'OK: {} is not off'.format(opt.name)
255 # VersionCheck provides enough info
256 assert(opt.result.startswith('OK: version')), \
257 'unexpected OK description "{}"'.format(opt.result)
259 self.result = self.opts[0].result
262 class AND(ComplexOptCheck):
263 # self.opts[0] is the option that this AND-check is about.
265 # AND(<suboption>, <main_option>)
266 # Suboption is not checked if checking of the main_option is failed.
267 # AND(<X_is_disabled>, <old_X_is_disabled>)
269 for i, opt in reversed(list(enumerate(self.opts))):
272 self.result = opt.result
274 if not opt.result.startswith('OK'):
275 # This FAIL is caused by additional checks,
276 # and not by the main option that this AND-check is about.
277 # Describe the reason of the FAIL.
278 if opt.result.startswith('FAIL: \"') or opt.result == 'FAIL: is not found':
279 self.result = 'FAIL: {} is not "{}"'.format(opt.name, opt.expected)
280 elif opt.result == 'FAIL: is not present':
281 self.result = 'FAIL: {} is not present'.format(opt.name)
282 elif opt.result == 'FAIL: is off':
283 self.result = 'FAIL: {} is off'.format(opt.name)
284 elif opt.result == 'FAIL: is off, not found':
285 self.result = 'FAIL: {} is off, not found'.format(opt.name)
287 # VersionCheck provides enough info
288 self.result = opt.result
289 assert(opt.result.startswith('FAIL: version')), \
290 'unexpected FAIL description "{}"'.format(opt.result)
294 def detect_arch(fname, archs):
295 with open(fname, 'r') as f:
296 arch_pattern = re.compile("CONFIG_[a-zA-Z0-9_]*=y")
298 for line in f.readlines():
299 if arch_pattern.match(line):
300 option, _ = line[7:].split('=', 1)
305 return None, 'more than one supported architecture is detected'
307 return None, 'failed to detect architecture'
311 def detect_kernel_version(fname):
312 with open(fname, 'r') as f:
313 ver_pattern = re.compile("# Linux/.* Kernel Configuration")
314 for line in f.readlines():
315 if ver_pattern.match(line):
319 ver_numbers = ver_str.split('.')
320 if len(ver_numbers) < 3 or not ver_numbers[0].isdigit() or not ver_numbers[1].isdigit():
321 msg = 'failed to parse the version "' + ver_str + '"'
323 return (int(ver_numbers[0]), int(ver_numbers[1])), None
324 return None, 'no kernel version detected'
327 def detect_compiler(fname):
330 with open(fname, 'r') as f:
331 gcc_version_pattern = re.compile("CONFIG_GCC_VERSION=[0-9]*")
332 clang_version_pattern = re.compile("CONFIG_CLANG_VERSION=[0-9]*")
333 for line in f.readlines():
334 if gcc_version_pattern.match(line):
335 gcc_version = line[19:-1]
336 if clang_version_pattern.match(line):
337 clang_version = line[21:-1]
338 if not gcc_version or not clang_version:
339 return None, 'no CONFIG_GCC_VERSION or CONFIG_CLANG_VERSION'
340 if gcc_version == '0' and clang_version != '0':
341 return 'CLANG ' + clang_version, 'OK'
342 if gcc_version != '0' and clang_version == '0':
343 return 'GCC ' + gcc_version, 'OK'
344 sys.exit('[!] ERROR: invalid GCC_VERSION and CLANG_VERSION: {} {}'.format(gcc_version, clang_version))
347 def add_kconfig_checks(l, arch):
348 # Calling the KconfigCheck class constructor:
349 # KconfigCheck(reason, decision, name, expected)
351 # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
352 # when the tool doesn't check the cmdline.
354 efi_not_set = KconfigCheck('-', '-', 'EFI', 'is not set')
355 cc_is_gcc = KconfigCheck('-', '-', 'CC_IS_GCC', 'y') # exists since v4.18
356 cc_is_clang = KconfigCheck('-', '-', 'CC_IS_CLANG', 'y') # exists since v4.18
358 modules_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'MODULES', 'is not set')
359 devmem_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'DEVMEM', 'is not set') # refers to LOCKDOWN
360 bpf_syscall_not_set = KconfigCheck('cut_attack_surface', 'lockdown', 'BPF_SYSCALL', 'is not set') # refers to LOCKDOWN
362 # 'self_protection', 'defconfig'
363 l += [KconfigCheck('self_protection', 'defconfig', 'BUG', 'y')]
364 l += [KconfigCheck('self_protection', 'defconfig', 'SLUB_DEBUG', 'y')]
365 l += [KconfigCheck('self_protection', 'defconfig', 'THREAD_INFO_IN_TASK', 'y')]
366 gcc_plugins_support_is_set = KconfigCheck('self_protection', 'defconfig', 'GCC_PLUGINS', 'y')
367 l += [gcc_plugins_support_is_set]
368 iommu_support_is_set = KconfigCheck('self_protection', 'defconfig', 'IOMMU_SUPPORT', 'y')
369 l += [iommu_support_is_set] # is needed for mitigating DMA attacks
370 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR', 'y'),
371 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR', 'y'),
372 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_REGULAR', 'y'),
373 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_AUTO', 'y'),
374 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
375 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_STRONG', 'y'),
376 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
377 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_KERNEL_RWX', 'y'),
378 KconfigCheck('self_protection', 'defconfig', 'DEBUG_RODATA', 'y'))] # before v4.11
379 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_MODULE_RWX', 'y'),
380 KconfigCheck('self_protection', 'defconfig', 'DEBUG_SET_MODULE_RONX', 'y'),
381 modules_not_set)] # DEBUG_SET_MODULE_RONX was before v4.11
382 l += [OR(KconfigCheck('self_protection', 'defconfig', 'REFCOUNT_FULL', 'y'),
383 VersionCheck((5, 5)))] # REFCOUNT_FULL is enabled by default since v5.5
384 if arch in ('X86_64', 'ARM64', 'X86_32'):
385 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y')]
386 if arch in ('X86_64', 'ARM64'):
387 l += [KconfigCheck('self_protection', 'defconfig', 'VMAP_STACK', 'y')]
388 if arch in ('X86_64', 'X86_32'):
389 l += [KconfigCheck('self_protection', 'defconfig', 'X86_MCE', 'y')]
390 l += [KconfigCheck('self_protection', 'defconfig', 'X86_MCE_INTEL', 'y')]
391 l += [KconfigCheck('self_protection', 'defconfig', 'X86_MCE_AMD', 'y')]
392 l += [KconfigCheck('self_protection', 'defconfig', 'MICROCODE', 'y')] # is needed for mitigating CPU bugs
393 l += [KconfigCheck('self_protection', 'defconfig', 'RETPOLINE', 'y')]
394 l += [KconfigCheck('self_protection', 'defconfig', 'SYN_COOKIES', 'y')] # another reason?
395 l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_SMAP', 'y'),
396 VersionCheck((5, 19)))] # X86_SMAP is enabled by default since v5.19
397 l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_UMIP', 'y'),
398 KconfigCheck('self_protection', 'defconfig', 'X86_INTEL_UMIP', 'y'))]
399 if arch in ('ARM64', 'ARM'):
400 l += [KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_PER_TASK', 'y')]
402 l += [KconfigCheck('self_protection', 'defconfig', 'PAGE_TABLE_ISOLATION', 'y')]
403 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MEMORY', 'y')]
404 l += [AND(KconfigCheck('self_protection', 'defconfig', 'INTEL_IOMMU', 'y'),
405 iommu_support_is_set)]
406 l += [AND(KconfigCheck('self_protection', 'defconfig', 'AMD_IOMMU', 'y'),
407 iommu_support_is_set)]
409 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PAN', 'y')]
410 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_EPAN', 'y')]
411 l += [KconfigCheck('self_protection', 'defconfig', 'UNMAP_KERNEL_AT_EL0', 'y')]
412 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_E0PD', 'y')]
413 l += [KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y')]
414 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PTR_AUTH_KERNEL', 'y')]
415 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_BTI_KERNEL', 'y')]
416 l += [KconfigCheck('self_protection', 'defconfig', 'MITIGATE_SPECTRE_BRANCH_HISTORY', 'y')]
417 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_MTE', 'y')]
418 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MODULE_REGION_FULL', 'y')]
419 l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_EL2_VECTORS', 'y'),
420 AND(KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y'),
421 VersionCheck((5, 9))))] # HARDEN_EL2_VECTORS was included in RANDOMIZE_BASE in v5.9
422 l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y'),
423 VersionCheck((5, 10)))] # HARDEN_BRANCH_PREDICTOR is enabled by default since v5.10
425 l += [KconfigCheck('self_protection', 'defconfig', 'CPU_SW_DOMAIN_PAN', 'y')]
426 l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y')]
427 l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_HISTORY', 'y')]
429 # 'self_protection', 'kspp'
430 l += [KconfigCheck('self_protection', 'kspp', 'BUG_ON_DATA_CORRUPTION', 'y')]
431 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_WX', 'y')]
432 l += [KconfigCheck('self_protection', 'kspp', 'SCHED_STACK_END_CHECK', 'y')]
433 l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_HARDENED', 'y')]
434 l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_RANDOM', 'y')]
435 l += [KconfigCheck('self_protection', 'kspp', 'SHUFFLE_PAGE_ALLOCATOR', 'y')]
436 l += [KconfigCheck('self_protection', 'kspp', 'FORTIFY_SOURCE', 'y')]
437 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_LIST', 'y')]
438 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_VIRTUAL', 'y')]
439 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_SG', 'y')]
440 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_CREDENTIALS', 'y')]
441 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_NOTIFIERS', 'y')]
442 l += [KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y')]
443 l += [KconfigCheck('self_protection', 'kspp', 'KFENCE', 'y')]
444 l += [KconfigCheck('self_protection', 'kspp', 'WERROR', 'y')]
445 l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y')]
446 l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set')] # true if IOMMU_DEFAULT_DMA_STRICT is set
447 l += [KconfigCheck('self_protection', 'kspp', 'ZERO_CALL_USED_REGS', 'y')]
448 l += [KconfigCheck('self_protection', 'kspp', 'HW_RANDOM_TPM', 'y')]
449 l += [KconfigCheck('self_protection', 'kspp', 'STATIC_USERMODEHELPER', 'y')] # needs userspace support
450 l += [KconfigCheck('self_protection', 'kspp', 'SCHED_CORE', 'y')]
451 randstruct_is_set = OR(KconfigCheck('self_protection', 'kspp', 'RANDSTRUCT_FULL', 'y'),
452 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_RANDSTRUCT', 'y'))
453 l += [randstruct_is_set]
454 l += [AND(KconfigCheck('self_protection', 'kspp', 'RANDSTRUCT_PERFORMANCE', 'is not set'),
455 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_RANDSTRUCT_PERFORMANCE', 'is not set'),
457 hardened_usercopy_is_set = KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y')
458 l += [hardened_usercopy_is_set]
459 l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
460 hardened_usercopy_is_set)]
461 l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_PAGESPAN', 'is not set'),
462 hardened_usercopy_is_set)]
463 l += [AND(KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_LATENT_ENTROPY', 'y'),
464 gcc_plugins_support_is_set)]
465 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG', 'y'),
467 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_ALL', 'y'),
469 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_SHA512', 'y'),
471 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_FORCE', 'y'),
472 modules_not_set)] # refers to LOCKDOWN
473 l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_STACK_ALL_ZERO', 'y'),
474 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STRUCTLEAK_BYREF_ALL', 'y'))]
475 l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
476 KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'))]
477 # CONFIG_INIT_ON_FREE_DEFAULT_ON was added in v5.3.
478 # CONFIG_PAGE_POISONING_ZERO was removed in v5.11.
479 # Starting from v5.11 CONFIG_PAGE_POISONING unconditionally checks
480 # the 0xAA poison pattern on allocation.
481 # That brings higher performance penalty.
482 l += [OR(KconfigCheck('self_protection', 'kspp', 'EFI_DISABLE_PCI_DMA', 'y'),
484 l += [OR(KconfigCheck('self_protection', 'kspp', 'RESET_ATTACK_MITIGATION', 'y'),
485 efi_not_set)] # needs userspace support (systemd)
486 ubsan_bounds_is_set = KconfigCheck('self_protection', 'kspp', 'UBSAN_BOUNDS', 'y')
487 l += [ubsan_bounds_is_set]
488 l += [OR(KconfigCheck('self_protection', 'kspp', 'UBSAN_LOCAL_BOUNDS', 'y'),
489 AND(ubsan_bounds_is_set,
491 l += [AND(KconfigCheck('self_protection', 'kspp', 'UBSAN_TRAP', 'y'),
493 KconfigCheck('self_protection', 'kspp', 'UBSAN_SHIFT', 'is not set'),
494 KconfigCheck('self_protection', 'kspp', 'UBSAN_DIV_ZERO', 'is not set'),
495 KconfigCheck('self_protection', 'kspp', 'UBSAN_UNREACHABLE', 'is not set'),
496 KconfigCheck('self_protection', 'kspp', 'UBSAN_BOOL', 'is not set'),
497 KconfigCheck('self_protection', 'kspp', 'UBSAN_ENUM', 'is not set'),
498 KconfigCheck('self_protection', 'kspp', 'UBSAN_ALIGNMENT', 'is not set'))] # only array index bounds checking with traps
499 if arch in ('X86_64', 'ARM64', 'X86_32'):
500 l += [AND(KconfigCheck('self_protection', 'kspp', 'UBSAN_SANITIZE_ALL', 'y'),
501 ubsan_bounds_is_set)] # ARCH_HAS_UBSAN_SANITIZE_ALL is not enabled for ARM
502 stackleak_is_set = KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STACKLEAK', 'y')
503 l += [AND(stackleak_is_set, gcc_plugins_support_is_set)]
504 l += [AND(KconfigCheck('self_protection', 'kspp', 'STACKLEAK_METRICS', 'is not set'),
506 gcc_plugins_support_is_set)]
507 l += [AND(KconfigCheck('self_protection', 'kspp', 'STACKLEAK_RUNTIME_DISABLE', 'is not set'),
509 gcc_plugins_support_is_set)]
510 l += [KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y')]
511 if arch in ('X86_64', 'ARM64'):
512 cfi_clang_is_set = KconfigCheck('self_protection', 'kspp', 'CFI_CLANG', 'y')
513 l += [cfi_clang_is_set]
514 l += [AND(KconfigCheck('self_protection', 'kspp', 'CFI_PERMISSIVE', 'is not set'),
516 if arch in ('X86_64', 'X86_32'):
517 l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '65536')]
518 l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU_DEFAULT_ON', 'y'),
519 iommu_support_is_set)]
520 if arch in ('ARM64', 'ARM'):
521 l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '32768')]
522 l += [KconfigCheck('self_protection', 'kspp', 'SYN_COOKIES', 'y')] # another reason?
524 l += [KconfigCheck('self_protection', 'kspp', 'SLS', 'y')] # vs CVE-2021-26341 in Straight-Line-Speculation
525 l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU_SVM', 'y'),
526 iommu_support_is_set)]
527 l += [AND(KconfigCheck('self_protection', 'kspp', 'AMD_IOMMU_V2', 'y'),
528 iommu_support_is_set)]
530 l += [KconfigCheck('self_protection', 'kspp', 'ARM64_SW_TTBR0_PAN', 'y')]
531 l += [KconfigCheck('self_protection', 'kspp', 'SHADOW_CALL_STACK', 'y')]
532 l += [KconfigCheck('self_protection', 'kspp', 'KASAN_HW_TAGS', 'y')]
534 l += [KconfigCheck('self_protection', 'kspp', 'PAGE_TABLE_ISOLATION', 'y')]
535 l += [KconfigCheck('self_protection', 'kspp', 'HIGHMEM64G', 'y')]
536 l += [KconfigCheck('self_protection', 'kspp', 'X86_PAE', 'y')]
537 l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU', 'y'),
538 iommu_support_is_set)]
540 # 'self_protection', 'clipos'
541 l += [KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set')]
544 if arch in ('X86_64', 'ARM64', 'X86_32'):
545 l += [KconfigCheck('security_policy', 'defconfig', 'SECURITY', 'y')] # and choose your favourite LSM
547 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY', 'y')] # and choose your favourite LSM
548 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_YAMA', 'y')]
549 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LANDLOCK', 'y')]
550 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_DISABLE', 'is not set')]
551 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_BOOTPARAM', 'is not set')]
552 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_DEVELOP', 'is not set')]
553 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LOCKDOWN_LSM', 'y')]
554 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LOCKDOWN_LSM_EARLY', 'y')]
555 l += [KconfigCheck('security_policy', 'kspp', 'LOCK_DOWN_KERNEL_FORCE_CONFIDENTIALITY', 'y')]
556 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_WRITABLE_HOOKS', 'is not set')] # refers to SECURITY_SELINUX_DISABLE
558 # 'cut_attack_surface', 'defconfig'
559 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP', 'y')]
560 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP_FILTER', 'y')]
561 l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'BPF_UNPRIV_DEFAULT_OFF', 'y'),
562 bpf_syscall_not_set)] # see unprivileged_bpf_disabled
563 if arch in ('X86_64', 'ARM64', 'X86_32'):
564 l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'STRICT_DEVMEM', 'y'),
565 devmem_not_set)] # refers to LOCKDOWN
567 # 'cut_attack_surface', 'kspp'
568 l += [KconfigCheck('cut_attack_surface', 'kspp', 'SECURITY_DMESG_RESTRICT', 'y')]
569 l += [KconfigCheck('cut_attack_surface', 'kspp', 'ACPI_CUSTOM_METHOD', 'is not set')] # refers to LOCKDOWN
570 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_BRK', 'is not set')]
571 l += [KconfigCheck('cut_attack_surface', 'kspp', 'DEVKMEM', 'is not set')] # refers to LOCKDOWN
572 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_VDSO', 'is not set')]
573 l += [KconfigCheck('cut_attack_surface', 'kspp', 'BINFMT_MISC', 'is not set')]
574 l += [KconfigCheck('cut_attack_surface', 'kspp', 'INET_DIAG', 'is not set')]
575 l += [KconfigCheck('cut_attack_surface', 'kspp', 'KEXEC', 'is not set')] # refers to LOCKDOWN
576 l += [KconfigCheck('cut_attack_surface', 'kspp', 'PROC_KCORE', 'is not set')] # refers to LOCKDOWN
577 l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_PTYS', 'is not set')]
578 l += [KconfigCheck('cut_attack_surface', 'kspp', 'HIBERNATION', 'is not set')] # refers to LOCKDOWN
579 l += [KconfigCheck('cut_attack_surface', 'kspp', 'IA32_EMULATION', 'is not set')]
580 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_X32', 'is not set')]
581 l += [KconfigCheck('cut_attack_surface', 'kspp', 'MODIFY_LDT_SYSCALL', 'is not set')]
582 l += [KconfigCheck('cut_attack_surface', 'kspp', 'OABI_COMPAT', 'is not set')]
583 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_MSR', 'is not set')] # refers to LOCKDOWN
584 l += [modules_not_set]
585 l += [devmem_not_set]
586 l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'IO_STRICT_DEVMEM', 'y'),
587 devmem_not_set)] # refers to LOCKDOWN
588 l += [AND(KconfigCheck('cut_attack_surface', 'kspp', 'LDISC_AUTOLOAD', 'is not set'),
589 KconfigCheck('cut_attack_surface', 'kspp', 'LDISC_AUTOLOAD', 'is present'))]
591 l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y')] # 'vsyscall=none'
593 l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'STRICT_DEVMEM', 'y'),
594 devmem_not_set)] # refers to LOCKDOWN
596 # 'cut_attack_surface', 'grsec'
597 l += [KconfigCheck('cut_attack_surface', 'grsec', 'ZSMALLOC_STAT', 'is not set')]
598 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PAGE_OWNER', 'is not set')]
599 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_KMEMLEAK', 'is not set')]
600 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BINFMT_AOUT', 'is not set')]
601 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KPROBE_EVENTS', 'is not set')]
602 l += [KconfigCheck('cut_attack_surface', 'grsec', 'UPROBE_EVENTS', 'is not set')]
603 l += [KconfigCheck('cut_attack_surface', 'grsec', 'GENERIC_TRACER', 'is not set')] # refers to LOCKDOWN
604 l += [KconfigCheck('cut_attack_surface', 'grsec', 'FUNCTION_TRACER', 'is not set')]
605 l += [KconfigCheck('cut_attack_surface', 'grsec', 'STACK_TRACER', 'is not set')]
606 l += [KconfigCheck('cut_attack_surface', 'grsec', 'HIST_TRIGGERS', 'is not set')]
607 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BLK_DEV_IO_TRACE', 'is not set')]
608 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_VMCORE', 'is not set')]
609 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_PAGE_MONITOR', 'is not set')]
610 l += [KconfigCheck('cut_attack_surface', 'grsec', 'USELIB', 'is not set')]
611 l += [KconfigCheck('cut_attack_surface', 'grsec', 'CHECKPOINT_RESTORE', 'is not set')]
612 l += [KconfigCheck('cut_attack_surface', 'grsec', 'USERFAULTFD', 'is not set')]
613 l += [KconfigCheck('cut_attack_surface', 'grsec', 'HWPOISON_INJECT', 'is not set')]
614 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MEM_SOFT_DIRTY', 'is not set')]
615 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEVPORT', 'is not set')] # refers to LOCKDOWN
616 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set')] # refers to LOCKDOWN
617 l += [KconfigCheck('cut_attack_surface', 'grsec', 'NOTIFIER_ERROR_INJECTION', 'is not set')]
618 l += [KconfigCheck('cut_attack_surface', 'grsec', 'FAIL_FUTEX', 'is not set')]
619 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PUNIT_ATOM_DEBUG', 'is not set')]
620 l += [KconfigCheck('cut_attack_surface', 'grsec', 'ACPI_CONFIGFS', 'is not set')]
621 l += [KconfigCheck('cut_attack_surface', 'grsec', 'EDAC_DEBUG', 'is not set')]
622 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DRM_I915_DEBUG', 'is not set')]
623 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BCACHE_CLOSURES_DEBUG', 'is not set')]
624 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DVB_C8SECTPFE', 'is not set')]
625 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_SLRAM', 'is not set')]
626 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_PHRAM', 'is not set')]
627 l += [KconfigCheck('cut_attack_surface', 'grsec', 'IO_URING', 'is not set')]
628 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCMP', 'is not set')]
629 l += [KconfigCheck('cut_attack_surface', 'grsec', 'RSEQ', 'is not set')]
630 l += [KconfigCheck('cut_attack_surface', 'grsec', 'LATENCYTOP', 'is not set')]
631 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCOV', 'is not set')]
632 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROVIDE_OHCI1394_DMA_INIT', 'is not set')]
633 l += [KconfigCheck('cut_attack_surface', 'grsec', 'SUNRPC_DEBUG', 'is not set')]
634 l += [AND(KconfigCheck('cut_attack_surface', 'grsec', 'PTDUMP_DEBUGFS', 'is not set'),
635 KconfigCheck('cut_attack_surface', 'grsec', 'X86_PTDUMP', 'is not set'))]
637 # 'cut_attack_surface', 'maintainer'
638 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'DRM_LEGACY', 'is not set')] # recommended by Daniel Vetter in /issues/38
639 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'FB', 'is not set')] # recommended by Daniel Vetter in /issues/38
640 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'VT', 'is not set')] # recommended by Daniel Vetter in /issues/38
641 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD', 'is not set')] # recommended by Denis Efremov in /pull/54
642 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD_RAWCMD', 'is not set')] # recommended by Denis Efremov in /pull/62
644 # 'cut_attack_surface', 'grapheneos'
645 l += [KconfigCheck('cut_attack_surface', 'grapheneos', 'AIO', 'is not set')]
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 :)
661 if arch in ('X86_64', 'X86_32'):
662 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_INTEL_TSX_MODE_OFF', 'y')] # tsx=off
664 # 'cut_attack_surface', 'lockdown'
665 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'EFI_TEST', 'is not set')] # refers to LOCKDOWN
666 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'MMIOTRACE_TEST', 'is not set')] # refers to LOCKDOWN
667 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'KPROBES', 'is not set')] # refers to LOCKDOWN
668 l += [bpf_syscall_not_set] # refers to LOCKDOWN
670 # 'cut_attack_surface', 'my'
671 l += [KconfigCheck('cut_attack_surface', 'my', 'MMIOTRACE', 'is not set')] # refers to LOCKDOWN (permissive)
672 l += [KconfigCheck('cut_attack_surface', 'my', 'LIVEPATCH', 'is not set')]
673 l += [KconfigCheck('cut_attack_surface', 'my', 'IP_DCCP', 'is not set')]
674 l += [KconfigCheck('cut_attack_surface', 'my', 'IP_SCTP', 'is not set')]
675 l += [KconfigCheck('cut_attack_surface', 'my', 'FTRACE', 'is not set')] # refers to LOCKDOWN
676 l += [KconfigCheck('cut_attack_surface', 'my', 'VIDEO_VIVID', 'is not set')]
677 l += [KconfigCheck('cut_attack_surface', 'my', 'INPUT_EVBUG', 'is not set')] # Can be used as a keylogger
678 l += [KconfigCheck('cut_attack_surface', 'my', 'KGDB', 'is not set')]
679 l += [OR(KconfigCheck('cut_attack_surface', 'my', 'TRIM_UNUSED_KSYMS', 'y'),
683 if arch in ('X86_64', 'ARM64', 'X86_32'):
684 l += [KconfigCheck('harden_userspace', 'defconfig', 'INTEGRITY', 'y')]
686 l += [KconfigCheck('harden_userspace', 'my', 'INTEGRITY', 'y')]
688 l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_PTR_AUTH', 'y')]
689 l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_BTI', 'y')]
690 if arch in ('ARM', 'X86_32'):
691 l += [KconfigCheck('harden_userspace', 'defconfig', 'VMSPLIT_3G', 'y')]
692 if arch in ('X86_64', 'ARM64'):
693 l += [KconfigCheck('harden_userspace', 'clipos', 'ARCH_MMAP_RND_BITS', '32')]
694 if arch in ('X86_32', 'ARM'):
695 l += [KconfigCheck('harden_userspace', 'my', 'ARCH_MMAP_RND_BITS', '16')]
698 def add_cmdline_checks(l, arch):
699 # Calling the CmdlineCheck class constructor:
700 # CmdlineCheck(reason, decision, name, expected)
702 # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
703 # when the tool doesn't check the cmdline.
705 # [!] Make sure that values of the options in CmdlineChecks need normalization.
706 # For more info see normalize_cmdline_options().
708 # A common pattern for checking the 'param_x' cmdline parameter
709 # that __overrides__ the 'PARAM_X_DEFAULT' kconfig option:
710 # l += [OR(CmdlineCheck(reason, decision, 'param_x', '1'),
711 # AND(KconfigCheck(reason, decision, 'PARAM_X_DEFAULT_ON', 'y'),
712 # CmdlineCheck(reason, decision, 'param_x, 'is not set')))]
714 # Here we don't check the kconfig options or minimal kernel version
715 # required for the cmdline parameters. That would make the checks
716 # very complex and not give a 100% guarantee anyway.
718 # 'self_protection', 'defconfig'
719 l += [CmdlineCheck('self_protection', 'defconfig', 'nosmep', 'is not set')]
720 l += [CmdlineCheck('self_protection', 'defconfig', 'nosmap', 'is not set')]
721 l += [CmdlineCheck('self_protection', 'defconfig', 'nokaslr', 'is not set')]
722 l += [CmdlineCheck('self_protection', 'defconfig', 'nopti', 'is not set')]
723 l += [CmdlineCheck('self_protection', 'defconfig', 'nospectre_v1', 'is not set')]
724 l += [CmdlineCheck('self_protection', 'defconfig', 'nospectre_v2', 'is not set')]
725 l += [CmdlineCheck('self_protection', 'defconfig', 'nospec_store_bypass_disable', 'is not set')]
726 l += [CmdlineCheck('self_protection', 'defconfig', 'arm64.nobti', 'is not set')]
727 l += [CmdlineCheck('self_protection', 'defconfig', 'arm64.nopauth', 'is not set')]
728 l += [CmdlineCheck('self_protection', 'defconfig', 'arm64.nomte', 'is not set')]
729 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'mitigations', 'is not off'),
730 CmdlineCheck('self_protection', 'defconfig', 'mitigations', 'is not set'))]
731 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'spectre_v2', 'is not off'),
732 CmdlineCheck('self_protection', 'defconfig', 'spectre_v2', 'is not set'))]
733 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'spectre_v2_user', 'is not off'),
734 CmdlineCheck('self_protection', 'defconfig', 'spectre_v2_user', 'is not set'))]
735 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'spec_store_bypass_disable', 'is not off'),
736 CmdlineCheck('self_protection', 'defconfig', 'spec_store_bypass_disable', 'is not set'))]
737 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'l1tf', 'is not off'),
738 CmdlineCheck('self_protection', 'defconfig', 'l1tf', 'is not set'))]
739 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'mds', 'is not off'),
740 CmdlineCheck('self_protection', 'defconfig', 'mds', 'is not set'))]
741 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'tsx_async_abort', 'is not off'),
742 CmdlineCheck('self_protection', 'defconfig', 'tsx_async_abort', 'is not set'))]
743 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'srbds', 'is not off'),
744 CmdlineCheck('self_protection', 'defconfig', 'srbds', 'is not set'))]
745 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'mmio_stale_data', 'is not off'),
746 CmdlineCheck('self_protection', 'defconfig', 'mmio_stale_data', 'is not set'))]
747 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'retbleed', 'is not off'),
748 CmdlineCheck('self_protection', 'defconfig', 'retbleed', 'is not set'))]
750 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'ssbd', 'kernel'),
751 CmdlineCheck('self_protection', 'my', 'ssbd', 'force-on'),
752 CmdlineCheck('self_protection', 'defconfig', 'ssbd', 'is not set'))]
753 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', 'full'),
754 AND(KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y'),
755 CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set')))]
757 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', '1'),
758 CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set'))]
760 # 'self_protection', 'kspp'
761 l += [CmdlineCheck('self_protection', 'kspp', 'nosmt', 'is present')]
762 l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', '1'),
763 AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y'),
764 CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', 'is not set')))]
765 l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_free', '1'),
766 AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
767 CmdlineCheck('self_protection', 'kspp', 'init_on_free', 'is not set')),
768 AND(CmdlineCheck('self_protection', 'kspp', 'page_poison', '1'),
769 KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'),
770 CmdlineCheck('self_protection', 'kspp', 'slub_debug', 'P')))]
771 l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_nomerge', 'is present'),
772 AND(KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set'),
773 CmdlineCheck('self_protection', 'kspp', 'slab_merge', 'is not set')))]
774 l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.strict', '1'),
775 AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y'),
776 CmdlineCheck('self_protection', 'kspp', 'iommu.strict', 'is not set')))]
777 l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', '0'),
778 AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set'),
779 CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', 'is not set')))]
780 # The cmdline checks compatible with the kconfig recommendations of the KSPP project...
781 l += [OR(CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', '1'),
782 AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y'),
783 CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', 'is not set')))]
784 l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', '0'),
785 AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
786 CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', 'is not set')))]
788 if arch in ('X86_64', 'ARM64', 'X86_32'):
789 l += [OR(CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', '1'),
790 AND(KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y'),
791 CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', 'is not set')))]
792 if arch in ('X86_64', 'X86_32'):
793 l += [AND(CmdlineCheck('self_protection', 'kspp', 'pti', 'on'),
794 CmdlineCheck('self_protection', 'defconfig', 'nopti', 'is not set'))]
796 # 'self_protection', 'clipos'
797 l += [CmdlineCheck('self_protection', 'clipos', 'page_alloc.shuffle', '1')]
799 # 'cut_attack_surface', 'kspp'
801 l += [OR(CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'none'),
802 AND(KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y'),
803 CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'is not set')))]
805 # 'cut_attack_surface', 'grsec'
806 # The cmdline checks compatible with the kconfig options disabled by grsecurity...
807 l += [OR(CmdlineCheck('cut_attack_surface', 'grsec', 'debugfs', 'off'),
808 KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set'))] # ... the end
810 # 'cut_attack_surface', 'my'
811 l += [CmdlineCheck('cut_attack_surface', 'my', 'sysrq_always_enabled', 'is not set')]
813 def print_unknown_options(checklist, parsed_options):
817 if o1.type != 'complex':
818 known_options.append(o1.name)
821 if o2.type != 'complex':
822 if hasattr(o2, 'name'):
823 known_options.append(o2.name)
826 assert(o3.type != 'complex'), \
827 'unexpected ComplexOptCheck inside {}'.format(o2.name)
828 if hasattr(o3, 'name'):
829 known_options.append(o3.name)
831 for option, value in parsed_options.items():
832 if option not in known_options:
833 print('[?] No check for option {} ({})'.format(option, value))
836 def print_checklist(mode, checklist, with_results):
840 output.append(o.json_dump(with_results))
841 print(json.dumps(output))
848 print('=' * sep_line_len)
849 print('{:^40}|{:^7}|{:^12}|{:^10}|{:^18}'.format('option name', 'type', 'desired val', 'decision', 'reason'), end='')
851 print('| {}'.format('check result'), end='')
853 print('=' * sep_line_len)
856 for opt in checklist:
858 if mode == 'show_ok':
859 if not opt.result.startswith('OK'):
861 if mode == 'show_fail':
862 if not opt.result.startswith('FAIL'):
864 opt.table_print(mode, with_results)
866 if mode == 'verbose':
867 print('-' * sep_line_len)
872 fail_count = len(list(filter(lambda opt: opt.result.startswith('FAIL'), checklist)))
874 ok_count = len(list(filter(lambda opt: opt.result.startswith('OK'), checklist)))
876 if mode == 'show_ok':
877 fail_suppressed = ' (suppressed in output)'
878 if mode == 'show_fail':
879 ok_suppressed = ' (suppressed in output)'
881 print('[+] Config check is finished: \'OK\' - {}{} / \'FAIL\' - {}{}'.format(ok_count, ok_suppressed, fail_count, fail_suppressed))
884 def populate_simple_opt_with_data(opt, data, data_type):
885 assert(opt.type != 'complex'), \
886 'unexpected ComplexOptCheck "{}"'.format(opt.name)
887 assert(opt.type in SIMPLE_OPTION_TYPES), \
888 'invalid opt type "{}"'.format(opt.type)
889 assert(data_type in SIMPLE_OPTION_TYPES), \
890 'invalid data type "{}"'.format(data_type)
892 if data_type != opt.type:
895 if data_type in ('kconfig', 'cmdline'):
896 opt.state = data.get(opt.name, None)
898 assert(data_type == 'version'), \
899 'unexpected data type "{}"'.format(data_type)
903 def populate_opt_with_data(opt, data, data_type):
904 if opt.type == 'complex':
906 if o.type == 'complex':
907 # Recursion for nested ComplexOptCheck objects
908 populate_opt_with_data(o, data, data_type)
910 populate_simple_opt_with_data(o, data, data_type)
912 assert(opt.type in ('kconfig', 'cmdline')), \
913 'bad type "{}" for a simple check'.format(opt.type)
914 populate_simple_opt_with_data(opt, data, data_type)
917 def populate_with_data(checklist, data, data_type):
918 for opt in checklist:
919 populate_opt_with_data(opt, data, data_type)
922 def perform_checks(checklist):
923 for opt in checklist:
927 def parse_kconfig_file(parsed_options, fname):
928 with open(fname, 'r') as f:
929 opt_is_on = re.compile("CONFIG_[a-zA-Z0-9_]*=[a-zA-Z0-9_\"]*")
930 opt_is_off = re.compile("# CONFIG_[a-zA-Z0-9_]* is not set")
932 for line in f.readlines():
937 if opt_is_on.match(line):
938 option, value = line.split('=', 1)
939 if value == 'is not set':
940 sys.exit('[!] ERROR: bad enabled kconfig option "{}"'.format(line))
941 elif opt_is_off.match(line):
942 option, value = line[2:].split(' ', 1)
943 if value != 'is not set':
944 sys.exit('[!] ERROR: bad disabled kconfig option "{}"'.format(line))
946 if option in parsed_options:
947 sys.exit('[!] ERROR: kconfig option "{}" exists multiple times'.format(line))
950 parsed_options[option] = value
953 def normalize_cmdline_options(option, value):
954 # Don't normalize the cmdline option values if
955 # the Linux kernel doesn't use kstrtobool() for them
956 if option == 'debugfs':
957 # See debugfs_kernel() in fs/debugfs/inode.c
959 if option == 'mitigations':
960 # See mitigations_parse_cmdline() in kernel/cpu.c
963 # See pti_check_boottime_disable() in arch/x86/mm/pti.c
965 if option == 'spectre_v2':
966 # See spectre_v2_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
968 if option == 'spectre_v2_user':
969 # See spectre_v2_parse_user_cmdline() in arch/x86/kernel/cpu/bugs.c
971 if option == 'spec_store_bypass_disable':
972 # See ssb_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
975 # See l1tf_cmdline() in arch/x86/kernel/cpu/bugs.c
978 # See mds_cmdline() in arch/x86/kernel/cpu/bugs.c
980 if option == 'tsx_async_abort':
981 # See tsx_async_abort_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
983 if option == 'srbds':
984 # See srbds_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
986 if option == 'mmio_stale_data':
987 # See mmio_stale_data_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
989 if option == 'retbleed':
990 # See retbleed_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
993 # Implement a limited part of the kstrtobool() logic
994 if value in ('1', 'on', 'On', 'ON', 'y', 'Y', 'yes', 'Yes', 'YES'):
996 if value in ('0', 'off', 'Off', 'OFF', 'n', 'N', 'no', 'No', 'NO'):
999 # Preserve unique values
1003 def parse_cmdline_file(parsed_options, fname):
1004 with open(fname, 'r') as f:
1010 sys.exit('[!] ERROR: more than one line in "{}"'.format(fname))
1014 name, value = opt.split('=', 1)
1017 value = '' # '' is not None
1018 value = normalize_cmdline_options(name, value)
1019 parsed_options[name] = value
1024 # * verbose mode for
1025 # - reporting about unknown kernel options in the kconfig
1026 # - verbose printing of ComplexOptCheck items
1027 # * json mode for printing the results in JSON format
1028 report_modes = ['verbose', 'json', 'show_ok', 'show_fail']
1029 supported_archs = ['X86_64', 'X86_32', 'ARM64', 'ARM']
1030 parser = ArgumentParser(prog='kconfig-hardened-check',
1031 description='A tool for checking the security hardening options of the Linux kernel')
1032 parser.add_argument('--version', action='version', version='%(prog)s ' + __version__)
1033 parser.add_argument('-p', '--print', choices=supported_archs,
1034 help='print security hardening preferences for the selected architecture')
1035 parser.add_argument('-c', '--config',
1036 help='check the kernel kconfig file against these preferences')
1037 parser.add_argument('-l', '--cmdline',
1038 help='check the kernel cmdline file against these preferences')
1039 parser.add_argument('-m', '--mode', choices=report_modes,
1040 help='choose the report mode')
1041 args = parser.parse_args()
1047 print('[+] Special report mode: {}'.format(mode))
1049 config_checklist = []
1053 sys.exit('[!] ERROR: --config and --print can\'t be used together')
1056 print('[+] Kconfig file to check: {}'.format(args.config))
1058 print('[+] Kernel cmdline file to check: {}'.format(args.cmdline))
1060 arch, msg = detect_arch(args.config, supported_archs)
1062 sys.exit('[!] ERROR: {}'.format(msg))
1064 print('[+] Detected architecture: {}'.format(arch))
1066 kernel_version, msg = detect_kernel_version(args.config)
1067 if not kernel_version:
1068 sys.exit('[!] ERROR: {}'.format(msg))
1070 print('[+] Detected kernel version: {}.{}'.format(kernel_version[0], kernel_version[1]))
1072 compiler, msg = detect_compiler(args.config)
1075 print('[+] Detected compiler: {}'.format(compiler))
1077 print('[-] Can\'t detect the compiler: {}'.format(msg))
1079 # add relevant kconfig checks to the checklist
1080 add_kconfig_checks(config_checklist, arch)
1083 # add relevant cmdline checks to the checklist
1084 add_cmdline_checks(config_checklist, arch)
1086 # populate the checklist with the parsed kconfig data
1087 parsed_kconfig_options = OrderedDict()
1088 parse_kconfig_file(parsed_kconfig_options, args.config)
1089 populate_with_data(config_checklist, parsed_kconfig_options, 'kconfig')
1090 populate_with_data(config_checklist, kernel_version, 'version')
1093 # populate the checklist with the parsed kconfig data
1094 parsed_cmdline_options = OrderedDict()
1095 parse_cmdline_file(parsed_cmdline_options, args.cmdline)
1096 populate_with_data(config_checklist, parsed_cmdline_options, 'cmdline')
1098 # now everything is ready for performing the checks
1099 perform_checks(config_checklist)
1101 # finally print the results
1102 if mode == 'verbose':
1103 print_unknown_options(config_checklist, parsed_kconfig_options)
1104 print_checklist(mode, config_checklist, True)
1108 sys.exit('[!] ERROR: checking cmdline doesn\'t work without checking kconfig')
1111 if mode in ('show_ok', 'show_fail'):
1112 sys.exit('[!] ERROR: wrong mode "{}" for --print'.format(mode))
1114 add_kconfig_checks(config_checklist, arch)
1115 add_cmdline_checks(config_checklist, arch)
1117 print('[+] Printing kernel security hardening preferences for {}...'.format(arch))
1118 print_checklist(mode, config_checklist, False)