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 sysctls:
14 # kernel.kptr_restrict=2 (or 1?)
15 # kernel.dmesg_restrict=1 (also see the kconfig option)
16 # kernel.perf_event_paranoid=3
17 # kernel.kexec_load_disabled=1
18 # kernel.yama.ptrace_scope=3
19 # user.max_user_namespaces=0
20 # what about bpf_jit_enable?
21 # kernel.unprivileged_bpf_disabled=1
22 # net.core.bpf_jit_harden=2
23 # vm.unprivileged_userfaultfd=0
24 # (at first, it disabled unprivileged userfaultfd,
25 # and since v5.11 it enables unprivileged userfaultfd for user-mode only)
26 # vm.mmap_min_addr has a good value
27 # dev.tty.ldisc_autoload=0
28 # fs.protected_symlinks=1
29 # fs.protected_hardlinks=1
30 # fs.protected_fifos=2
31 # fs.protected_regular=2
33 # kernel.modules_disabled=1
34 # kernel.randomize_va_space = 2
35 # nosmt sysfs control file
38 # pylint: disable=missing-module-docstring,missing-class-docstring,missing-function-docstring
39 # pylint: disable=line-too-long,invalid-name,too-many-branches,too-many-statements
43 from argparse import ArgumentParser
44 from collections import OrderedDict
47 from .__about__ import __version__
49 SIMPLE_OPTION_TYPES = ('kconfig', 'version', 'cmdline')
52 def __init__(self, reason, decision, name, expected):
53 assert(name and name == name.strip() and len(name.split()) == 1), \
54 'invalid name "{}" for {}'.format(name, self.__class__.__name__)
57 assert(decision and decision == decision.strip() and len(decision.split()) == 1), \
58 'invalid decision "{}" for "{}" check'.format(decision, name)
59 self.decision = decision
61 assert(reason and reason == reason.strip() and len(reason.split()) == 1), \
62 'invalid reason "{}" for "{}" check'.format(reason, name)
65 assert(expected and expected == expected.strip()), \
66 'invalid expected value "{}" for "{}" check (1)'.format(expected, name)
67 val_len = len(expected.split())
69 assert(expected in ('is not set', 'is not off')), \
70 'invalid expected value "{}" for "{}" check (2)'.format(expected, name)
72 assert(expected == 'is present'), \
73 'invalid expected value "{}" for "{}" check (3)'.format(expected, name)
75 assert(val_len == 1), \
76 'invalid expected value "{}" for "{}" check (4)'.format(expected, name)
77 self.expected = expected
87 # handle the 'is present' check
88 if self.expected == 'is present':
89 if self.state is None:
90 self.result = 'FAIL: is not present'
92 self.result = 'OK: is present'
95 # handle the 'is not off' option check
96 if self.expected == 'is not off':
97 if self.state == 'off':
98 self.result = 'FAIL: is off'
100 self.result = 'FAIL: is off, "0"'
101 elif self.state is None:
102 self.result = 'FAIL: is off, not found'
104 self.result = 'OK: is not off, "' + self.state + '"'
107 # handle the option value check
108 if self.expected == self.state:
110 elif self.state is None:
111 if self.expected == 'is not set':
112 self.result = 'OK: is not found'
114 self.result = 'FAIL: is not found'
116 self.result = 'FAIL: "' + self.state + '"'
118 def table_print(self, _mode, with_results):
119 print('{:<40}|{:^7}|{:^12}|{:^10}|{:^18}'.format(self.name, self.type, self.expected, self.decision, self.reason), end='')
121 print('| {}'.format(self.result), end='')
123 def json_dump(self, with_results):
124 dump = [self.name, self.type, self.expected, self.decision, self.reason]
126 dump.append(self.result)
130 class KconfigCheck(OptCheck):
131 def __init__(self, *args, **kwargs):
132 super().__init__(*args, **kwargs)
133 self.name = 'CONFIG_' + self.name
140 class CmdlineCheck(OptCheck):
147 def __init__(self, ver_expected):
148 assert(ver_expected and isinstance(ver_expected, tuple) and len(ver_expected) == 2), \
149 'invalid version "{}" for VersionCheck'.format(ver_expected)
150 self.ver_expected = ver_expected
159 if self.ver[0] > self.ver_expected[0]:
160 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
162 if self.ver[0] < self.ver_expected[0]:
163 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
165 if self.ver[1] >= self.ver_expected[1]:
166 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
168 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
170 def table_print(self, _mode, with_results):
171 ver_req = 'kernel version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
172 print('{:<91}'.format(ver_req), end='')
174 print('| {}'.format(self.result), end='')
177 class ComplexOptCheck:
178 def __init__(self, *opts):
181 'empty {} check'.format(self.__class__.__name__)
182 assert(len(self.opts) != 1), \
183 'useless {} check: {}'.format(self.__class__.__name__, opts)
184 assert(isinstance(opts[0], (KconfigCheck, CmdlineCheck))), \
185 'invalid {} check: {}'.format(self.__class__.__name__, opts)
194 return self.opts[0].name
198 return self.opts[0].expected
200 def table_print(self, mode, with_results):
201 if mode == 'verbose':
202 print(' {:87}'.format('<<< ' + self.__class__.__name__ + ' >>>'), end='')
204 print('| {}'.format(self.result), end='')
207 o.table_print(mode, with_results)
210 o.table_print(mode, False)
212 print('| {}'.format(self.result), end='')
214 def json_dump(self, with_results):
215 dump = self.opts[0].json_dump(False)
217 dump.append(self.result)
221 class OR(ComplexOptCheck):
222 # self.opts[0] is the option that this OR-check is about.
224 # OR(<X_is_hardened>, <X_is_disabled>)
225 # OR(<X_is_hardened>, <old_X_is_hardened>)
227 for i, opt in enumerate(self.opts):
229 if opt.result.startswith('OK'):
230 self.result = opt.result
231 # Add more info for additional checks:
233 if opt.result == 'OK':
234 self.result = 'OK: {} is "{}"'.format(opt.name, opt.expected)
235 elif opt.result == 'OK: is not found':
236 self.result = 'OK: {} is not found'.format(opt.name)
237 elif opt.result == 'OK: is present':
238 self.result = 'OK: {} is present'.format(opt.name)
239 elif opt.result.startswith('OK: is not off'):
240 self.result = 'OK: {} is not off'.format(opt.name)
242 # VersionCheck provides enough info
243 assert(opt.result.startswith('OK: version')), \
244 'unexpected OK description "{}"'.format(opt.result)
246 self.result = self.opts[0].result
249 class AND(ComplexOptCheck):
250 # self.opts[0] is the option that this AND-check is about.
252 # AND(<suboption>, <main_option>)
253 # Suboption is not checked if checking of the main_option is failed.
254 # AND(<X_is_disabled>, <old_X_is_disabled>)
256 for i, opt in reversed(list(enumerate(self.opts))):
259 self.result = opt.result
261 if not opt.result.startswith('OK'):
262 # This FAIL is caused by additional checks,
263 # and not by the main option that this AND-check is about.
264 # Describe the reason of the FAIL.
265 if opt.result.startswith('FAIL: \"') or opt.result == 'FAIL: is not found':
266 self.result = 'FAIL: {} is not "{}"'.format(opt.name, opt.expected)
267 elif opt.result == 'FAIL: is not present':
268 self.result = 'FAIL: {} is not present'.format(opt.name)
269 elif opt.result in ('FAIL: is off', 'FAIL: is off, "0"'):
270 self.result = 'FAIL: {} is off'.format(opt.name)
271 elif opt.result == 'FAIL: is off, not found':
272 self.result = 'FAIL: {} is off, not found'.format(opt.name)
274 # VersionCheck provides enough info
275 self.result = opt.result
276 assert(opt.result.startswith('FAIL: version')), \
277 'unexpected FAIL description "{}"'.format(opt.result)
281 def detect_arch(fname, archs):
282 with open(fname, 'r') as f:
283 arch_pattern = re.compile("CONFIG_[a-zA-Z0-9_]*=y")
285 for line in f.readlines():
286 if arch_pattern.match(line):
287 option, _ = line[7:].split('=', 1)
292 return None, 'more than one supported architecture is detected'
294 return None, 'failed to detect architecture'
298 def detect_kernel_version(fname):
299 with open(fname, 'r') as f:
300 ver_pattern = re.compile("# Linux/.* Kernel Configuration")
301 for line in f.readlines():
302 if ver_pattern.match(line):
306 ver_numbers = ver_str.split('.')
307 if len(ver_numbers) < 3 or not ver_numbers[0].isdigit() or not ver_numbers[1].isdigit():
308 msg = 'failed to parse the version "' + ver_str + '"'
310 return (int(ver_numbers[0]), int(ver_numbers[1])), None
311 return None, 'no kernel version detected'
314 def detect_compiler(fname):
317 with open(fname, 'r') as f:
318 gcc_version_pattern = re.compile("CONFIG_GCC_VERSION=[0-9]*")
319 clang_version_pattern = re.compile("CONFIG_CLANG_VERSION=[0-9]*")
320 for line in f.readlines():
321 if gcc_version_pattern.match(line):
322 gcc_version = line[19:-1]
323 if clang_version_pattern.match(line):
324 clang_version = line[21:-1]
325 if not gcc_version or not clang_version:
326 return None, 'no CONFIG_GCC_VERSION or CONFIG_CLANG_VERSION'
327 if gcc_version == '0' and clang_version != '0':
328 return 'CLANG ' + clang_version, 'OK'
329 if gcc_version != '0' and clang_version == '0':
330 return 'GCC ' + gcc_version, 'OK'
331 sys.exit('[!] ERROR: invalid GCC_VERSION and CLANG_VERSION: {} {}'.format(gcc_version, clang_version))
334 def add_kconfig_checks(l, arch):
335 # Calling the KconfigCheck class constructor:
336 # KconfigCheck(reason, decision, name, expected)
338 # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
339 # when the tool doesn't check the cmdline.
341 efi_not_set = KconfigCheck('-', '-', 'EFI', 'is not set')
342 cc_is_gcc = KconfigCheck('-', '-', 'CC_IS_GCC', 'y') # exists since v4.18
343 cc_is_clang = KconfigCheck('-', '-', 'CC_IS_CLANG', 'y') # exists since v4.18
345 modules_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'MODULES', 'is not set')
346 devmem_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'DEVMEM', 'is not set') # refers to LOCKDOWN
347 bpf_syscall_not_set = KconfigCheck('cut_attack_surface', 'lockdown', 'BPF_SYSCALL', 'is not set') # refers to LOCKDOWN
349 # 'self_protection', 'defconfig'
350 l += [KconfigCheck('self_protection', 'defconfig', 'BUG', 'y')]
351 l += [KconfigCheck('self_protection', 'defconfig', 'SLUB_DEBUG', 'y')]
352 l += [KconfigCheck('self_protection', 'defconfig', 'THREAD_INFO_IN_TASK', 'y')]
353 gcc_plugins_support_is_set = KconfigCheck('self_protection', 'defconfig', 'GCC_PLUGINS', 'y')
354 l += [gcc_plugins_support_is_set]
355 iommu_support_is_set = KconfigCheck('self_protection', 'defconfig', 'IOMMU_SUPPORT', 'y')
356 l += [iommu_support_is_set] # is needed for mitigating DMA attacks
357 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR', 'y'),
358 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR', 'y'),
359 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_REGULAR', 'y'),
360 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_AUTO', 'y'),
361 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
362 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_STRONG', 'y'),
363 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
364 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_KERNEL_RWX', 'y'),
365 KconfigCheck('self_protection', 'defconfig', 'DEBUG_RODATA', 'y'))] # before v4.11
366 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_MODULE_RWX', 'y'),
367 KconfigCheck('self_protection', 'defconfig', 'DEBUG_SET_MODULE_RONX', 'y'),
368 modules_not_set)] # DEBUG_SET_MODULE_RONX was before v4.11
369 l += [OR(KconfigCheck('self_protection', 'defconfig', 'REFCOUNT_FULL', 'y'),
370 VersionCheck((5, 5)))] # REFCOUNT_FULL is enabled by default since v5.5
371 if arch in ('X86_64', 'ARM64', 'X86_32'):
372 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y')]
373 if arch in ('X86_64', 'ARM64', 'ARM'):
374 l += [KconfigCheck('self_protection', 'defconfig', 'VMAP_STACK', 'y')]
375 if arch in ('X86_64', 'X86_32'):
376 l += [KconfigCheck('self_protection', 'defconfig', 'DEBUG_WX', 'y')]
377 l += [KconfigCheck('self_protection', 'defconfig', 'WERROR', 'y')]
378 l += [KconfigCheck('self_protection', 'defconfig', 'X86_MCE', 'y')]
379 l += [KconfigCheck('self_protection', 'defconfig', 'X86_MCE_INTEL', 'y')]
380 l += [KconfigCheck('self_protection', 'defconfig', 'X86_MCE_AMD', 'y')]
381 l += [KconfigCheck('self_protection', 'defconfig', 'MICROCODE', 'y')] # is needed for mitigating CPU bugs
382 l += [KconfigCheck('self_protection', 'defconfig', 'RETPOLINE', 'y')]
383 l += [KconfigCheck('self_protection', 'defconfig', 'SYN_COOKIES', 'y')] # another reason?
384 l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_SMAP', 'y'),
385 VersionCheck((5, 19)))] # X86_SMAP is enabled by default since v5.19
386 l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_UMIP', 'y'),
387 KconfigCheck('self_protection', 'defconfig', 'X86_INTEL_UMIP', 'y'))]
388 if arch in ('ARM64', 'ARM'):
389 l += [KconfigCheck('self_protection', 'defconfig', 'IOMMU_DEFAULT_DMA_STRICT', 'y')]
390 l += [KconfigCheck('self_protection', 'defconfig', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set')] # true if IOMMU_DEFAULT_DMA_STRICT is set
391 l += [KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_PER_TASK', 'y')]
393 l += [KconfigCheck('self_protection', 'defconfig', 'PAGE_TABLE_ISOLATION', 'y')]
394 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MEMORY', 'y')]
395 l += [AND(KconfigCheck('self_protection', 'defconfig', 'INTEL_IOMMU', 'y'),
396 iommu_support_is_set)]
397 l += [AND(KconfigCheck('self_protection', 'defconfig', 'AMD_IOMMU', 'y'),
398 iommu_support_is_set)]
400 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PAN', 'y')]
401 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_EPAN', 'y')]
402 l += [KconfigCheck('self_protection', 'defconfig', 'UNMAP_KERNEL_AT_EL0', 'y')]
403 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_E0PD', 'y')]
404 l += [KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y')]
405 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PTR_AUTH_KERNEL', 'y')]
406 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_BTI_KERNEL', 'y')]
407 l += [KconfigCheck('self_protection', 'defconfig', 'MITIGATE_SPECTRE_BRANCH_HISTORY', 'y')]
408 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_MTE', 'y')]
409 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MODULE_REGION_FULL', 'y')]
410 l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_EL2_VECTORS', 'y'),
411 AND(KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y'),
412 VersionCheck((5, 9))))] # HARDEN_EL2_VECTORS was included in RANDOMIZE_BASE in v5.9
413 l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y'),
414 VersionCheck((5, 10)))] # HARDEN_BRANCH_PREDICTOR is enabled by default since v5.10
416 l += [KconfigCheck('self_protection', 'defconfig', 'CPU_SW_DOMAIN_PAN', 'y')]
417 l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y')]
418 l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_HISTORY', 'y')]
420 # 'self_protection', 'kspp'
421 l += [KconfigCheck('self_protection', 'kspp', 'BUG_ON_DATA_CORRUPTION', 'y')]
422 l += [KconfigCheck('self_protection', 'kspp', 'SCHED_STACK_END_CHECK', 'y')]
423 l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_HARDENED', 'y')]
424 l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_RANDOM', 'y')]
425 l += [KconfigCheck('self_protection', 'kspp', 'SHUFFLE_PAGE_ALLOCATOR', 'y')]
426 l += [KconfigCheck('self_protection', 'kspp', 'FORTIFY_SOURCE', 'y')]
427 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_LIST', 'y')]
428 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_VIRTUAL', 'y')]
429 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_SG', 'y')]
430 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_CREDENTIALS', 'y')]
431 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_NOTIFIERS', 'y')]
432 l += [KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y')]
433 l += [KconfigCheck('self_protection', 'kspp', 'KFENCE', 'y')]
434 l += [KconfigCheck('self_protection', 'kspp', 'ZERO_CALL_USED_REGS', 'y')]
435 l += [KconfigCheck('self_protection', 'kspp', 'HW_RANDOM_TPM', 'y')]
436 l += [KconfigCheck('self_protection', 'kspp', 'STATIC_USERMODEHELPER', 'y')] # needs userspace support
437 randstruct_is_set = OR(KconfigCheck('self_protection', 'kspp', 'RANDSTRUCT_FULL', 'y'),
438 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_RANDSTRUCT', 'y'))
439 l += [randstruct_is_set]
440 l += [AND(KconfigCheck('self_protection', 'kspp', 'RANDSTRUCT_PERFORMANCE', 'is not set'),
441 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_RANDSTRUCT_PERFORMANCE', 'is not set'),
443 hardened_usercopy_is_set = KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y')
444 l += [hardened_usercopy_is_set]
445 l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
446 hardened_usercopy_is_set)]
447 l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_PAGESPAN', 'is not set'),
448 hardened_usercopy_is_set)]
449 l += [AND(KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_LATENT_ENTROPY', 'y'),
450 gcc_plugins_support_is_set)]
451 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG', 'y'),
453 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_ALL', 'y'),
455 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_SHA512', 'y'),
457 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_FORCE', 'y'),
458 modules_not_set)] # refers to LOCKDOWN
459 l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_STACK_ALL_ZERO', 'y'),
460 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STRUCTLEAK_BYREF_ALL', 'y'))]
461 l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
462 KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'))]
463 # CONFIG_INIT_ON_FREE_DEFAULT_ON was added in v5.3.
464 # CONFIG_PAGE_POISONING_ZERO was removed in v5.11.
465 # Starting from v5.11 CONFIG_PAGE_POISONING unconditionally checks
466 # the 0xAA poison pattern on allocation.
467 # That brings higher performance penalty.
468 l += [OR(KconfigCheck('self_protection', 'kspp', 'EFI_DISABLE_PCI_DMA', 'y'),
470 l += [OR(KconfigCheck('self_protection', 'kspp', 'RESET_ATTACK_MITIGATION', 'y'),
471 efi_not_set)] # needs userspace support (systemd)
472 ubsan_bounds_is_set = KconfigCheck('self_protection', 'kspp', 'UBSAN_BOUNDS', 'y')
473 l += [ubsan_bounds_is_set]
474 l += [OR(KconfigCheck('self_protection', 'kspp', 'UBSAN_LOCAL_BOUNDS', 'y'),
475 AND(ubsan_bounds_is_set,
477 l += [AND(KconfigCheck('self_protection', 'kspp', 'UBSAN_TRAP', 'y'),
479 KconfigCheck('self_protection', 'kspp', 'UBSAN_SHIFT', 'is not set'),
480 KconfigCheck('self_protection', 'kspp', 'UBSAN_DIV_ZERO', 'is not set'),
481 KconfigCheck('self_protection', 'kspp', 'UBSAN_UNREACHABLE', 'is not set'),
482 KconfigCheck('self_protection', 'kspp', 'UBSAN_BOOL', 'is not set'),
483 KconfigCheck('self_protection', 'kspp', 'UBSAN_ENUM', 'is not set'),
484 KconfigCheck('self_protection', 'kspp', 'UBSAN_ALIGNMENT', 'is not set'))] # only array index bounds checking with traps
485 if arch in ('X86_64', 'ARM64', 'X86_32'):
486 l += [AND(KconfigCheck('self_protection', 'kspp', 'UBSAN_SANITIZE_ALL', 'y'),
487 ubsan_bounds_is_set)] # ARCH_HAS_UBSAN_SANITIZE_ALL is not enabled for ARM
488 stackleak_is_set = KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STACKLEAK', 'y')
489 l += [AND(stackleak_is_set, gcc_plugins_support_is_set)]
490 l += [AND(KconfigCheck('self_protection', 'kspp', 'STACKLEAK_METRICS', 'is not set'),
492 gcc_plugins_support_is_set)]
493 l += [AND(KconfigCheck('self_protection', 'kspp', 'STACKLEAK_RUNTIME_DISABLE', 'is not set'),
495 gcc_plugins_support_is_set)]
496 l += [KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y')]
497 if arch in ('X86_64', 'ARM64'):
498 cfi_clang_is_set = KconfigCheck('self_protection', 'kspp', 'CFI_CLANG', 'y')
499 l += [cfi_clang_is_set]
500 l += [AND(KconfigCheck('self_protection', 'kspp', 'CFI_PERMISSIVE', 'is not set'),
502 if arch in ('X86_64', 'X86_32'):
503 l += [KconfigCheck('self_protection', 'kspp', 'SCHED_CORE', 'y')]
504 l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '65536')]
505 l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y')]
506 l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set')] # true if IOMMU_DEFAULT_DMA_STRICT is set
507 l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU_DEFAULT_ON', 'y'),
508 iommu_support_is_set)]
509 if arch in ('ARM64', 'ARM'):
510 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_WX', 'y')]
511 l += [KconfigCheck('self_protection', 'kspp', 'WERROR', 'y')]
512 l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '32768')]
513 l += [KconfigCheck('self_protection', 'kspp', 'SYN_COOKIES', 'y')] # another reason?
515 l += [KconfigCheck('self_protection', 'kspp', 'SLS', 'y')] # vs CVE-2021-26341 in Straight-Line-Speculation
516 l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU_SVM', 'y'),
517 iommu_support_is_set)]
518 l += [AND(KconfigCheck('self_protection', 'kspp', 'AMD_IOMMU_V2', 'y'),
519 iommu_support_is_set)]
521 l += [KconfigCheck('self_protection', 'kspp', 'ARM64_SW_TTBR0_PAN', 'y')]
522 l += [KconfigCheck('self_protection', 'kspp', 'SHADOW_CALL_STACK', 'y')]
523 l += [KconfigCheck('self_protection', 'kspp', 'KASAN_HW_TAGS', 'y')] # see also: kasan=on, kasan.stacktrace=off, kasan.fault=panic
525 l += [KconfigCheck('self_protection', 'kspp', 'PAGE_TABLE_ISOLATION', 'y')]
526 l += [KconfigCheck('self_protection', 'kspp', 'HIGHMEM64G', 'y')]
527 l += [KconfigCheck('self_protection', 'kspp', 'X86_PAE', 'y')]
528 l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU', 'y'),
529 iommu_support_is_set)]
531 # 'self_protection', 'clipos'
532 l += [KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set')]
535 if arch in ('X86_64', 'ARM64', 'X86_32'):
536 l += [KconfigCheck('security_policy', 'defconfig', 'SECURITY', 'y')] # and choose your favourite LSM
538 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY', 'y')] # and choose your favourite LSM
539 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_YAMA', 'y')]
540 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LANDLOCK', 'y')]
541 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_DISABLE', 'is not set')]
542 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_BOOTPARAM', 'is not set')]
543 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_DEVELOP', 'is not set')]
544 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LOCKDOWN_LSM', 'y')]
545 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LOCKDOWN_LSM_EARLY', 'y')]
546 l += [KconfigCheck('security_policy', 'kspp', 'LOCK_DOWN_KERNEL_FORCE_CONFIDENTIALITY', 'y')]
547 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_WRITABLE_HOOKS', 'is not set')] # refers to SECURITY_SELINUX_DISABLE
549 # 'cut_attack_surface', 'defconfig'
550 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP', 'y')]
551 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP_FILTER', 'y')]
552 l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'BPF_UNPRIV_DEFAULT_OFF', 'y'),
553 bpf_syscall_not_set)] # see unprivileged_bpf_disabled
554 if arch in ('X86_64', 'ARM64', 'X86_32'):
555 l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'STRICT_DEVMEM', 'y'),
556 devmem_not_set)] # refers to LOCKDOWN
557 if arch in ('X86_64', 'X86_32'):
558 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'X86_INTEL_TSX_MODE_OFF', 'y')] # tsx=off
560 # 'cut_attack_surface', 'kspp'
561 l += [KconfigCheck('cut_attack_surface', 'kspp', 'SECURITY_DMESG_RESTRICT', 'y')]
562 l += [KconfigCheck('cut_attack_surface', 'kspp', 'ACPI_CUSTOM_METHOD', 'is not set')] # refers to LOCKDOWN
563 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_BRK', 'is not set')]
564 l += [KconfigCheck('cut_attack_surface', 'kspp', 'DEVKMEM', 'is not set')] # refers to LOCKDOWN
565 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_VDSO', 'is not set')]
566 l += [KconfigCheck('cut_attack_surface', 'kspp', 'BINFMT_MISC', 'is not set')]
567 l += [KconfigCheck('cut_attack_surface', 'kspp', 'INET_DIAG', 'is not set')]
568 l += [KconfigCheck('cut_attack_surface', 'kspp', 'KEXEC', 'is not set')] # refers to LOCKDOWN
569 l += [KconfigCheck('cut_attack_surface', 'kspp', 'PROC_KCORE', 'is not set')] # refers to LOCKDOWN
570 l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_PTYS', 'is not set')]
571 l += [KconfigCheck('cut_attack_surface', 'kspp', 'HIBERNATION', 'is not set')] # refers to LOCKDOWN
572 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT', 'is not set')]
573 l += [KconfigCheck('cut_attack_surface', 'kspp', 'IA32_EMULATION', 'is not set')]
574 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_X32', 'is not set')]
575 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_X32_ABI', 'is not set')]
576 l += [KconfigCheck('cut_attack_surface', 'kspp', 'MODIFY_LDT_SYSCALL', 'is not set')]
577 l += [KconfigCheck('cut_attack_surface', 'kspp', 'OABI_COMPAT', 'is not set')]
578 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_MSR', 'is not set')] # refers to LOCKDOWN
579 l += [modules_not_set]
580 l += [devmem_not_set]
581 l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'IO_STRICT_DEVMEM', 'y'),
582 devmem_not_set)] # refers to LOCKDOWN
583 l += [AND(KconfigCheck('cut_attack_surface', 'kspp', 'LDISC_AUTOLOAD', 'is not set'),
584 KconfigCheck('cut_attack_surface', 'kspp', 'LDISC_AUTOLOAD', 'is present'))]
586 l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y')] # 'vsyscall=none'
588 l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'STRICT_DEVMEM', 'y'),
589 devmem_not_set)] # refers to LOCKDOWN
591 # 'cut_attack_surface', 'grsec'
592 l += [KconfigCheck('cut_attack_surface', 'grsec', 'ZSMALLOC_STAT', 'is not set')]
593 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PAGE_OWNER', 'is not set')]
594 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_KMEMLEAK', 'is not set')]
595 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BINFMT_AOUT', 'is not set')]
596 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KPROBE_EVENTS', 'is not set')]
597 l += [KconfigCheck('cut_attack_surface', 'grsec', 'UPROBE_EVENTS', 'is not set')]
598 l += [KconfigCheck('cut_attack_surface', 'grsec', 'GENERIC_TRACER', 'is not set')] # refers to LOCKDOWN
599 l += [KconfigCheck('cut_attack_surface', 'grsec', 'FUNCTION_TRACER', 'is not set')]
600 l += [KconfigCheck('cut_attack_surface', 'grsec', 'STACK_TRACER', 'is not set')]
601 l += [KconfigCheck('cut_attack_surface', 'grsec', 'HIST_TRIGGERS', 'is not set')]
602 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BLK_DEV_IO_TRACE', 'is not set')]
603 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_VMCORE', 'is not set')]
604 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_PAGE_MONITOR', 'is not set')]
605 l += [KconfigCheck('cut_attack_surface', 'grsec', 'USELIB', 'is not set')]
606 l += [KconfigCheck('cut_attack_surface', 'grsec', 'CHECKPOINT_RESTORE', 'is not set')]
607 l += [KconfigCheck('cut_attack_surface', 'grsec', 'USERFAULTFD', 'is not set')]
608 l += [KconfigCheck('cut_attack_surface', 'grsec', 'HWPOISON_INJECT', 'is not set')]
609 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MEM_SOFT_DIRTY', 'is not set')]
610 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEVPORT', 'is not set')] # refers to LOCKDOWN
611 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set')] # refers to LOCKDOWN
612 l += [KconfigCheck('cut_attack_surface', 'grsec', 'NOTIFIER_ERROR_INJECTION', 'is not set')]
613 l += [KconfigCheck('cut_attack_surface', 'grsec', 'FAIL_FUTEX', 'is not set')]
614 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PUNIT_ATOM_DEBUG', 'is not set')]
615 l += [KconfigCheck('cut_attack_surface', 'grsec', 'ACPI_CONFIGFS', 'is not set')]
616 l += [KconfigCheck('cut_attack_surface', 'grsec', 'EDAC_DEBUG', 'is not set')]
617 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DRM_I915_DEBUG', 'is not set')]
618 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BCACHE_CLOSURES_DEBUG', 'is not set')]
619 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DVB_C8SECTPFE', 'is not set')]
620 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_SLRAM', 'is not set')]
621 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_PHRAM', 'is not set')]
622 l += [KconfigCheck('cut_attack_surface', 'grsec', 'IO_URING', 'is not set')]
623 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCMP', 'is not set')]
624 l += [KconfigCheck('cut_attack_surface', 'grsec', 'RSEQ', 'is not set')]
625 l += [KconfigCheck('cut_attack_surface', 'grsec', 'LATENCYTOP', 'is not set')]
626 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCOV', 'is not set')]
627 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROVIDE_OHCI1394_DMA_INIT', 'is not set')]
628 l += [KconfigCheck('cut_attack_surface', 'grsec', 'SUNRPC_DEBUG', 'is not set')]
629 l += [AND(KconfigCheck('cut_attack_surface', 'grsec', 'PTDUMP_DEBUGFS', 'is not set'),
630 KconfigCheck('cut_attack_surface', 'grsec', 'X86_PTDUMP', 'is not set'))]
632 # 'cut_attack_surface', 'maintainer'
633 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'DRM_LEGACY', 'is not set')] # recommended by Daniel Vetter in /issues/38
634 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'FB', 'is not set')] # recommended by Daniel Vetter in /issues/38
635 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'VT', 'is not set')] # recommended by Daniel Vetter in /issues/38
636 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD', 'is not set')] # recommended by Denis Efremov in /pull/54
637 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD_RAWCMD', 'is not set')] # recommended by Denis Efremov in /pull/62
639 # 'cut_attack_surface', 'clipos'
640 l += [KconfigCheck('cut_attack_surface', 'clipos', 'STAGING', 'is not set')]
641 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KSM', 'is not set')] # to prevent FLUSH+RELOAD attack
642 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KALLSYMS', 'is not set')]
643 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_VSYSCALL_EMULATION', 'is not set')]
644 l += [KconfigCheck('cut_attack_surface', 'clipos', 'MAGIC_SYSRQ', 'is not set')]
645 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KEXEC_FILE', 'is not set')] # refers to LOCKDOWN (permissive)
646 l += [KconfigCheck('cut_attack_surface', 'clipos', 'USER_NS', 'is not set')] # user.max_user_namespaces=0
647 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_CPUID', 'is not set')]
648 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_IOPL_IOPERM', 'is not set')] # refers to LOCKDOWN
649 l += [KconfigCheck('cut_attack_surface', 'clipos', 'ACPI_TABLE_UPGRADE', 'is not set')] # refers to LOCKDOWN
650 l += [KconfigCheck('cut_attack_surface', 'clipos', 'EFI_CUSTOM_SSDT_OVERLAYS', 'is not set')]
651 l += [KconfigCheck('cut_attack_surface', 'clipos', 'COREDUMP', 'is not set')] # cut userspace attack surface
652 # l += [KconfigCheck('cut_attack_surface', 'clipos', 'IKCONFIG', 'is not set')] # no, IKCONFIG is needed for this check :)
654 # 'cut_attack_surface', 'lockdown'
655 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'EFI_TEST', 'is not set')] # refers to LOCKDOWN
656 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'MMIOTRACE_TEST', 'is not set')] # refers to LOCKDOWN
657 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'KPROBES', 'is not set')] # refers to LOCKDOWN
658 l += [bpf_syscall_not_set] # refers to LOCKDOWN
660 # 'cut_attack_surface', 'my'
661 l += [KconfigCheck('cut_attack_surface', 'my', 'MMIOTRACE', 'is not set')] # refers to LOCKDOWN (permissive)
662 l += [KconfigCheck('cut_attack_surface', 'my', 'LIVEPATCH', 'is not set')]
663 l += [KconfigCheck('cut_attack_surface', 'my', 'IP_DCCP', 'is not set')]
664 l += [KconfigCheck('cut_attack_surface', 'my', 'IP_SCTP', 'is not set')]
665 l += [KconfigCheck('cut_attack_surface', 'my', 'FTRACE', 'is not set')] # refers to LOCKDOWN
666 l += [KconfigCheck('cut_attack_surface', 'my', 'VIDEO_VIVID', 'is not set')]
667 l += [KconfigCheck('cut_attack_surface', 'my', 'INPUT_EVBUG', 'is not set')] # Can be used as a keylogger
668 l += [KconfigCheck('cut_attack_surface', 'my', 'KGDB', 'is not set')]
669 l += [OR(KconfigCheck('cut_attack_surface', 'my', 'TRIM_UNUSED_KSYMS', 'y'),
673 if arch in ('X86_64', 'ARM64', 'X86_32'):
674 l += [KconfigCheck('harden_userspace', 'defconfig', 'INTEGRITY', 'y')]
676 l += [KconfigCheck('harden_userspace', 'my', 'INTEGRITY', 'y')]
678 l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_PTR_AUTH', 'y')]
679 l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_BTI', 'y')]
680 if arch in ('ARM', 'X86_32'):
681 l += [KconfigCheck('harden_userspace', 'defconfig', 'VMSPLIT_3G', 'y')]
682 if arch in ('X86_64', 'ARM64'):
683 l += [KconfigCheck('harden_userspace', 'clipos', 'ARCH_MMAP_RND_BITS', '32')]
684 if arch in ('X86_32', 'ARM'):
685 l += [KconfigCheck('harden_userspace', 'my', 'ARCH_MMAP_RND_BITS', '16')]
688 def add_cmdline_checks(l, arch):
689 # Calling the CmdlineCheck class constructor:
690 # CmdlineCheck(reason, decision, name, expected)
692 # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
693 # when the tool doesn't check the cmdline.
695 # [!] Make sure that values of the options in CmdlineChecks need normalization.
696 # For more info see normalize_cmdline_options().
698 # A common pattern for checking the 'param_x' cmdline parameter
699 # that __overrides__ the 'PARAM_X_DEFAULT' kconfig option:
700 # l += [OR(CmdlineCheck(reason, decision, 'param_x', '1'),
701 # AND(KconfigCheck(reason, decision, 'PARAM_X_DEFAULT_ON', 'y'),
702 # CmdlineCheck(reason, decision, 'param_x, 'is not set')))]
704 # Here we don't check the kconfig options or minimal kernel version
705 # required for the cmdline parameters. That would make the checks
706 # very complex and not give a 100% guarantee anyway.
708 # 'self_protection', 'defconfig'
709 l += [CmdlineCheck('self_protection', 'defconfig', 'nosmep', 'is not set')]
710 l += [CmdlineCheck('self_protection', 'defconfig', 'nosmap', 'is not set')]
711 l += [CmdlineCheck('self_protection', 'defconfig', 'nokaslr', 'is not set')]
712 l += [CmdlineCheck('self_protection', 'defconfig', 'nopti', 'is not set')]
713 l += [CmdlineCheck('self_protection', 'defconfig', 'nospectre_v1', 'is not set')]
714 l += [CmdlineCheck('self_protection', 'defconfig', 'nospectre_v2', 'is not set')]
715 l += [CmdlineCheck('self_protection', 'defconfig', 'nospectre_bhb', 'is not set')]
716 l += [CmdlineCheck('self_protection', 'defconfig', 'nospec_store_bypass_disable', 'is not set')]
717 l += [CmdlineCheck('self_protection', 'defconfig', 'arm64.nobti', 'is not set')]
718 l += [CmdlineCheck('self_protection', 'defconfig', 'arm64.nopauth', 'is not set')]
719 l += [CmdlineCheck('self_protection', 'defconfig', 'arm64.nomte', 'is not set')]
720 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'mitigations', 'is not off'),
721 CmdlineCheck('self_protection', 'defconfig', 'mitigations', 'is not set'))]
722 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'spectre_v2', 'is not off'),
723 CmdlineCheck('self_protection', 'defconfig', 'spectre_v2', 'is not set'))]
724 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'spectre_v2_user', 'is not off'),
725 CmdlineCheck('self_protection', 'defconfig', 'spectre_v2_user', 'is not set'))]
726 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'spec_store_bypass_disable', 'is not off'),
727 CmdlineCheck('self_protection', 'defconfig', 'spec_store_bypass_disable', 'is not set'))]
728 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'l1tf', 'is not off'),
729 CmdlineCheck('self_protection', 'defconfig', 'l1tf', 'is not set'))]
730 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'mds', 'is not off'),
731 CmdlineCheck('self_protection', 'defconfig', 'mds', 'is not set'))]
732 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'tsx_async_abort', 'is not off'),
733 CmdlineCheck('self_protection', 'defconfig', 'tsx_async_abort', 'is not set'))]
734 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'srbds', 'is not off'),
735 CmdlineCheck('self_protection', 'defconfig', 'srbds', 'is not set'))]
736 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'mmio_stale_data', 'is not off'),
737 CmdlineCheck('self_protection', 'defconfig', 'mmio_stale_data', 'is not set'))]
738 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'retbleed', 'is not off'),
739 CmdlineCheck('self_protection', 'defconfig', 'retbleed', 'is not set'))]
740 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'kpti', 'is not off'),
741 CmdlineCheck('self_protection', 'defconfig', 'kpti', 'is not set'))]
742 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'kvm.nx_huge_pages', 'is not off'),
743 CmdlineCheck('self_protection', 'defconfig', 'kvm.nx_huge_pages', 'is not set'))]
745 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'ssbd', 'kernel'),
746 CmdlineCheck('self_protection', 'my', 'ssbd', 'force-on'),
747 CmdlineCheck('self_protection', 'defconfig', 'ssbd', 'is not set'))]
748 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', 'full'),
749 AND(KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y'),
750 CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set')))]
752 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', '1'),
753 CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set'))]
755 # 'self_protection', 'kspp'
756 l += [CmdlineCheck('self_protection', 'kspp', 'nosmt', 'is present')]
757 l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', '1'),
758 AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y'),
759 CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', 'is not set')))]
760 l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_free', '1'),
761 AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
762 CmdlineCheck('self_protection', 'kspp', 'init_on_free', 'is not set')),
763 AND(CmdlineCheck('self_protection', 'kspp', 'page_poison', '1'),
764 KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'),
765 CmdlineCheck('self_protection', 'kspp', 'slub_debug', 'P')))]
766 l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_nomerge', 'is present'),
767 AND(KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set'),
768 CmdlineCheck('self_protection', 'kspp', 'slab_merge', 'is not set'),
769 CmdlineCheck('self_protection', 'clipos', 'slub_merge', 'is not set')))]
770 l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.strict', '1'),
771 AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y'),
772 CmdlineCheck('self_protection', 'kspp', 'iommu.strict', 'is not set')))]
773 l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', '0'),
774 AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set'),
775 CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', 'is not set')))]
776 # The cmdline checks compatible with the kconfig recommendations of the KSPP project...
777 l += [OR(CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', '1'),
778 AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y'),
779 CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', 'is not set')))]
780 l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', '0'),
781 AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
782 CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', 'is not set')))]
784 if arch in ('X86_64', 'ARM64', 'X86_32'):
785 l += [OR(CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', '1'),
786 AND(KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y'),
787 CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', 'is not set')))]
788 if arch in ('X86_64', 'X86_32'):
789 l += [AND(CmdlineCheck('self_protection', 'kspp', 'pti', 'on'),
790 CmdlineCheck('self_protection', 'defconfig', 'nopti', 'is not set'))]
792 # 'self_protection', 'clipos'
793 l += [CmdlineCheck('self_protection', 'clipos', 'page_alloc.shuffle', '1')]
794 if arch in ('X86_64', 'X86_32'):
795 l += [CmdlineCheck('self_protection', 'clipos', 'iommu', 'force')]
797 # 'cut_attack_surface', 'defconfig'
798 if arch in ('X86_64', 'X86_32'):
799 l += [OR(CmdlineCheck('cut_attack_surface', 'defconfig', 'tsx', 'off'),
800 AND(KconfigCheck('cut_attack_surface', 'defconfig', 'X86_INTEL_TSX_MODE_OFF', 'y'),
801 CmdlineCheck('cut_attack_surface', 'defconfig', 'tsx', 'is not set')))]
803 # 'cut_attack_surface', 'kspp'
805 l += [OR(CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'none'),
806 AND(KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y'),
807 CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'is not set')))]
809 # 'cut_attack_surface', 'grsec'
810 # The cmdline checks compatible with the kconfig options disabled by grsecurity...
811 l += [OR(CmdlineCheck('cut_attack_surface', 'grsec', 'debugfs', 'off'),
812 KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set'))] # ... the end
814 # 'cut_attack_surface', 'my'
815 l += [CmdlineCheck('cut_attack_surface', 'my', 'sysrq_always_enabled', 'is not set')]
817 def print_unknown_options(checklist, parsed_options):
821 if o1.type != 'complex':
822 known_options.append(o1.name)
825 if o2.type != 'complex':
826 if hasattr(o2, 'name'):
827 known_options.append(o2.name)
830 assert(o3.type != 'complex'), \
831 'unexpected ComplexOptCheck inside {}'.format(o2.name)
832 if hasattr(o3, 'name'):
833 known_options.append(o3.name)
835 for option, value in parsed_options.items():
836 if option not in known_options:
837 print('[?] No check for option {} ({})'.format(option, value))
840 def print_checklist(mode, checklist, with_results):
844 output.append(o.json_dump(with_results))
845 print(json.dumps(output))
852 print('=' * sep_line_len)
853 print('{:^40}|{:^7}|{:^12}|{:^10}|{:^18}'.format('option name', 'type', 'desired val', 'decision', 'reason'), end='')
855 print('| {}'.format('check result'), end='')
857 print('=' * sep_line_len)
860 for opt in checklist:
862 if mode == 'show_ok':
863 if not opt.result.startswith('OK'):
865 if mode == 'show_fail':
866 if not opt.result.startswith('FAIL'):
868 opt.table_print(mode, with_results)
870 if mode == 'verbose':
871 print('-' * sep_line_len)
876 fail_count = len(list(filter(lambda opt: opt.result.startswith('FAIL'), checklist)))
878 ok_count = len(list(filter(lambda opt: opt.result.startswith('OK'), checklist)))
880 if mode == 'show_ok':
881 fail_suppressed = ' (suppressed in output)'
882 if mode == 'show_fail':
883 ok_suppressed = ' (suppressed in output)'
885 print('[+] Config check is finished: \'OK\' - {}{} / \'FAIL\' - {}{}'.format(ok_count, ok_suppressed, fail_count, fail_suppressed))
888 def populate_simple_opt_with_data(opt, data, data_type):
889 assert(opt.type != 'complex'), \
890 'unexpected ComplexOptCheck "{}"'.format(opt.name)
891 assert(opt.type in SIMPLE_OPTION_TYPES), \
892 'invalid opt type "{}"'.format(opt.type)
893 assert(data_type in SIMPLE_OPTION_TYPES), \
894 'invalid data type "{}"'.format(data_type)
896 if data_type != opt.type:
899 if data_type in ('kconfig', 'cmdline'):
900 opt.state = data.get(opt.name, None)
902 assert(data_type == 'version'), \
903 'unexpected data type "{}"'.format(data_type)
907 def populate_opt_with_data(opt, data, data_type):
908 if opt.type == 'complex':
910 if o.type == 'complex':
911 # Recursion for nested ComplexOptCheck objects
912 populate_opt_with_data(o, data, data_type)
914 populate_simple_opt_with_data(o, data, data_type)
916 assert(opt.type in ('kconfig', 'cmdline')), \
917 'bad type "{}" for a simple check'.format(opt.type)
918 populate_simple_opt_with_data(opt, data, data_type)
921 def populate_with_data(checklist, data, data_type):
922 for opt in checklist:
923 populate_opt_with_data(opt, data, data_type)
926 def perform_checks(checklist):
927 for opt in checklist:
931 def parse_kconfig_file(parsed_options, fname):
932 with open(fname, 'r') as f:
933 opt_is_on = re.compile("CONFIG_[a-zA-Z0-9_]*=[a-zA-Z0-9_\"]*")
934 opt_is_off = re.compile("# CONFIG_[a-zA-Z0-9_]* is not set")
936 for line in f.readlines():
941 if opt_is_on.match(line):
942 option, value = line.split('=', 1)
943 if value == 'is not set':
944 sys.exit('[!] ERROR: bad enabled kconfig option "{}"'.format(line))
945 elif opt_is_off.match(line):
946 option, value = line[2:].split(' ', 1)
947 if value != 'is not set':
948 sys.exit('[!] ERROR: bad disabled kconfig option "{}"'.format(line))
950 if option in parsed_options:
951 sys.exit('[!] ERROR: kconfig option "{}" exists multiple times'.format(line))
954 parsed_options[option] = value
957 def normalize_cmdline_options(option, value):
958 # Don't normalize the cmdline option values if
959 # the Linux kernel doesn't use kstrtobool() for them
960 if option == 'debugfs':
961 # See debugfs_kernel() in fs/debugfs/inode.c
963 if option == 'mitigations':
964 # See mitigations_parse_cmdline() in kernel/cpu.c
967 # See pti_check_boottime_disable() in arch/x86/mm/pti.c
969 if option == 'spectre_v2':
970 # See spectre_v2_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
972 if option == 'spectre_v2_user':
973 # See spectre_v2_parse_user_cmdline() in arch/x86/kernel/cpu/bugs.c
975 if option == 'spec_store_bypass_disable':
976 # See ssb_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
979 # See l1tf_cmdline() in arch/x86/kernel/cpu/bugs.c
982 # See mds_cmdline() in arch/x86/kernel/cpu/bugs.c
984 if option == 'tsx_async_abort':
985 # See tsx_async_abort_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
987 if option == 'srbds':
988 # See srbds_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
990 if option == 'mmio_stale_data':
991 # See mmio_stale_data_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
993 if option == 'retbleed':
994 # See retbleed_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
997 # See tsx_init() in arch/x86/kernel/cpu/tsx.c
1000 # Implement a limited part of the kstrtobool() logic
1001 if value in ('1', 'on', 'On', 'ON', 'y', 'Y', 'yes', 'Yes', 'YES'):
1003 if value in ('0', 'off', 'Off', 'OFF', 'n', 'N', 'no', 'No', 'NO'):
1006 # Preserve unique values
1010 def parse_cmdline_file(parsed_options, fname):
1011 with open(fname, 'r') as f:
1017 sys.exit('[!] ERROR: more than one line in "{}"'.format(fname))
1021 name, value = opt.split('=', 1)
1024 value = '' # '' is not None
1025 value = normalize_cmdline_options(name, value)
1026 parsed_options[name] = value
1031 # * verbose mode for
1032 # - reporting about unknown kernel options in the kconfig
1033 # - verbose printing of ComplexOptCheck items
1034 # * json mode for printing the results in JSON format
1035 report_modes = ['verbose', 'json', 'show_ok', 'show_fail']
1036 supported_archs = ['X86_64', 'X86_32', 'ARM64', 'ARM']
1037 parser = ArgumentParser(prog='kconfig-hardened-check',
1038 description='A tool for checking the security hardening options of the Linux kernel')
1039 parser.add_argument('--version', action='version', version='%(prog)s ' + __version__)
1040 parser.add_argument('-p', '--print', choices=supported_archs,
1041 help='print security hardening preferences for the selected architecture')
1042 parser.add_argument('-c', '--config',
1043 help='check the kernel kconfig file against these preferences')
1044 parser.add_argument('-l', '--cmdline',
1045 help='check the kernel cmdline file against these preferences')
1046 parser.add_argument('-m', '--mode', choices=report_modes,
1047 help='choose the report mode')
1048 args = parser.parse_args()
1054 print('[+] Special report mode: {}'.format(mode))
1056 config_checklist = []
1060 sys.exit('[!] ERROR: --config and --print can\'t be used together')
1063 print('[+] Kconfig file to check: {}'.format(args.config))
1065 print('[+] Kernel cmdline file to check: {}'.format(args.cmdline))
1067 arch, msg = detect_arch(args.config, supported_archs)
1069 sys.exit('[!] ERROR: {}'.format(msg))
1071 print('[+] Detected architecture: {}'.format(arch))
1073 kernel_version, msg = detect_kernel_version(args.config)
1074 if not kernel_version:
1075 sys.exit('[!] ERROR: {}'.format(msg))
1077 print('[+] Detected kernel version: {}.{}'.format(kernel_version[0], kernel_version[1]))
1079 compiler, msg = detect_compiler(args.config)
1082 print('[+] Detected compiler: {}'.format(compiler))
1084 print('[-] Can\'t detect the compiler: {}'.format(msg))
1086 # add relevant kconfig checks to the checklist
1087 add_kconfig_checks(config_checklist, arch)
1090 # add relevant cmdline checks to the checklist
1091 add_cmdline_checks(config_checklist, arch)
1093 # populate the checklist with the parsed kconfig data
1094 parsed_kconfig_options = OrderedDict()
1095 parse_kconfig_file(parsed_kconfig_options, args.config)
1096 populate_with_data(config_checklist, parsed_kconfig_options, 'kconfig')
1097 populate_with_data(config_checklist, kernel_version, 'version')
1100 # populate the checklist with the parsed kconfig data
1101 parsed_cmdline_options = OrderedDict()
1102 parse_cmdline_file(parsed_cmdline_options, args.cmdline)
1103 populate_with_data(config_checklist, parsed_cmdline_options, 'cmdline')
1105 # now everything is ready, perform the checks
1106 perform_checks(config_checklist)
1108 if mode == 'verbose':
1109 # print the parsed options without the checks (for debugging)
1110 all_parsed_options = parsed_kconfig_options # assignment does not copy
1111 all_parsed_options.update(parsed_cmdline_options)
1112 print_unknown_options(config_checklist, all_parsed_options)
1114 # finally print the results
1115 print_checklist(mode, config_checklist, True)
1119 sys.exit('[!] ERROR: checking cmdline doesn\'t work without checking kconfig')
1122 if mode in ('show_ok', 'show_fail'):
1123 sys.exit('[!] ERROR: wrong mode "{}" for --print'.format(mode))
1125 add_kconfig_checks(config_checklist, arch)
1126 add_cmdline_checks(config_checklist, arch)
1128 print('[+] Printing kernel security hardening preferences for {}...'.format(arch))
1129 print_checklist(mode, config_checklist, False)