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)
29 # Hardware tag-based KASAN with arm64 Memory Tagging Extension (MTE):
31 # kasan.stacktrace=off
34 # N.B. Hardening sysctls:
35 # kernel.kptr_restrict=2 (or 1?)
36 # kernel.dmesg_restrict=1 (also see the kconfig option)
37 # kernel.perf_event_paranoid=3
38 # kernel.kexec_load_disabled=1
39 # kernel.yama.ptrace_scope=3
40 # user.max_user_namespaces=0
41 # what about bpf_jit_enable?
42 # kernel.unprivileged_bpf_disabled=1
43 # net.core.bpf_jit_harden=2
44 # vm.unprivileged_userfaultfd=0
45 # (at first, it disabled unprivileged userfaultfd,
46 # and since v5.11 it enables unprivileged userfaultfd for user-mode only)
47 # vm.mmap_min_addr has a good value
48 # dev.tty.ldisc_autoload=0
49 # fs.protected_symlinks=1
50 # fs.protected_hardlinks=1
51 # fs.protected_fifos=2
52 # fs.protected_regular=2
54 # kernel.modules_disabled=1
55 # kernel.randomize_va_space = 2
58 # pylint: disable=missing-module-docstring,missing-class-docstring,missing-function-docstring
59 # pylint: disable=line-too-long,invalid-name,too-many-branches,too-many-statements
63 from argparse import ArgumentParser
64 from collections import OrderedDict
67 from .__about__ import __version__
69 SIMPLE_OPTION_TYPES = ('kconfig', 'version', 'cmdline')
72 def __init__(self, reason, decision, name, expected):
73 assert(name and name == name.strip() and len(name.split()) == 1), \
74 'invalid name "{}" for {}'.format(name, self.__class__.__name__)
77 assert(decision and decision == decision.strip() and len(decision.split()) == 1), \
78 'invalid decision "{}" for "{}" check'.format(decision, name)
79 self.decision = decision
81 assert(reason and reason == reason.strip() and len(reason.split()) == 1), \
82 'invalid reason "{}" for "{}" check'.format(reason, name)
85 assert(expected and expected == expected.strip()), \
86 'invalid expected value "{}" for "{}" check (1)'.format(expected, name)
87 val_len = len(expected.split())
89 assert(expected == 'is not set' or expected == 'is not off'), \
90 'invalid expected value "{}" for "{}" check (2)'.format(expected, name)
92 assert(expected == 'is present'), \
93 'invalid expected value "{}" for "{}" check (3)'.format(expected, name)
95 assert(val_len == 1), \
96 'invalid expected value "{}" for "{}" check (4)'.format(expected, name)
97 self.expected = expected
107 # handle the 'is present' check
108 if self.expected == 'is present':
109 if self.state is None:
110 self.result = 'FAIL: is not present'
112 self.result = 'OK: is present'
115 # handle the 'is not off' option check
116 if self.expected == 'is not off':
117 if self.state == 'off':
118 self.result = 'FAIL: is off'
119 elif self.state is None:
120 self.result = 'FAIL: is off, not found'
122 self.result = 'OK: is not off, "' + self.state + '"'
125 # handle the option value check
126 if self.expected == self.state:
128 elif self.state is None:
129 if self.expected == 'is not set':
130 self.result = 'OK: is not found'
132 self.result = 'FAIL: is not found'
134 self.result = 'FAIL: "' + self.state + '"'
136 def table_print(self, _mode, with_results):
137 print('{:<40}|{:^7}|{:^12}|{:^10}|{:^18}'.format(self.name, self.type, self.expected, self.decision, self.reason), end='')
139 print('| {}'.format(self.result), end='')
141 def json_dump(self, with_results):
142 dump = [self.name, self.type, self.expected, self.decision, self.reason]
144 dump.append(self.result)
148 class KconfigCheck(OptCheck):
149 def __init__(self, *args, **kwargs):
150 super().__init__(*args, **kwargs)
151 self.name = 'CONFIG_' + self.name
158 class CmdlineCheck(OptCheck):
165 def __init__(self, ver_expected):
166 assert(ver_expected and isinstance(ver_expected, tuple) and len(ver_expected) == 2), \
167 'invalid version "{}" for VersionCheck'.format(ver_expected)
168 self.ver_expected = ver_expected
177 if self.ver[0] > self.ver_expected[0]:
178 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
180 if self.ver[0] < self.ver_expected[0]:
181 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
183 if self.ver[1] >= self.ver_expected[1]:
184 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
186 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
188 def table_print(self, _mode, with_results):
189 ver_req = 'kernel version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
190 print('{:<91}'.format(ver_req), end='')
192 print('| {}'.format(self.result), end='')
195 class ComplexOptCheck:
196 def __init__(self, *opts):
199 'empty {} check'.format(self.__class__.__name__)
200 assert(len(self.opts) != 1), \
201 'useless {} check: {}'.format(self.__class__.__name__, opts)
202 assert(isinstance(opts[0], (KconfigCheck, CmdlineCheck))), \
203 'invalid {} check: {}'.format(self.__class__.__name__, opts)
212 return self.opts[0].name
216 return self.opts[0].expected
218 def table_print(self, mode, with_results):
219 if mode == 'verbose':
220 print(' {:87}'.format('<<< ' + self.__class__.__name__ + ' >>>'), end='')
222 print('| {}'.format(self.result), end='')
225 o.table_print(mode, with_results)
228 o.table_print(mode, False)
230 print('| {}'.format(self.result), end='')
232 def json_dump(self, with_results):
233 dump = self.opts[0].json_dump(False)
235 dump.append(self.result)
239 class OR(ComplexOptCheck):
240 # self.opts[0] is the option that this OR-check is about.
242 # OR(<X_is_hardened>, <X_is_disabled>)
243 # OR(<X_is_hardened>, <old_X_is_hardened>)
245 for i, opt in enumerate(self.opts):
247 if opt.result.startswith('OK'):
248 self.result = opt.result
249 # Add more info for additional checks:
251 if opt.result == 'OK':
252 self.result = 'OK: {} is "{}"'.format(opt.name, opt.expected)
253 elif opt.result == 'OK: is not found':
254 self.result = 'OK: {} is not found'.format(opt.name)
255 elif opt.result == 'OK: is present':
256 self.result = 'OK: {} is present'.format(opt.name)
257 elif opt.result.startswith('OK: is not off'):
258 self.result = 'OK: {} is not off'.format(opt.name)
260 # VersionCheck provides enough info
261 assert(opt.result.startswith('OK: version')), \
262 'unexpected OK description "{}"'.format(opt.result)
264 self.result = self.opts[0].result
267 class AND(ComplexOptCheck):
268 # self.opts[0] is the option that this AND-check is about.
270 # AND(<suboption>, <main_option>)
271 # Suboption is not checked if checking of the main_option is failed.
272 # AND(<X_is_disabled>, <old_X_is_disabled>)
274 for i, opt in reversed(list(enumerate(self.opts))):
277 self.result = opt.result
279 if not opt.result.startswith('OK'):
280 # This FAIL is caused by additional checks,
281 # and not by the main option that this AND-check is about.
282 # Describe the reason of the FAIL.
283 if opt.result.startswith('FAIL: \"') or opt.result == 'FAIL: is not found':
284 self.result = 'FAIL: {} is not "{}"'.format(opt.name, opt.expected)
285 elif opt.result == 'FAIL: is not present':
286 self.result = 'FAIL: {} is not present'.format(opt.name)
287 elif opt.result == 'FAIL: is off':
288 self.result = 'FAIL: {} is off'.format(opt.name)
289 elif opt.result == 'FAIL: is off, not found':
290 self.result = 'FAIL: {} is off, not found'.format(opt.name)
292 # VersionCheck provides enough info
293 self.result = opt.result
294 assert(opt.result.startswith('FAIL: version')), \
295 'unexpected FAIL description "{}"'.format(opt.result)
299 def detect_arch(fname, archs):
300 with open(fname, 'r') as f:
301 arch_pattern = re.compile("CONFIG_[a-zA-Z0-9_]*=y")
303 for line in f.readlines():
304 if arch_pattern.match(line):
305 option, _ = line[7:].split('=', 1)
310 return None, 'more than one supported architecture is detected'
312 return None, 'failed to detect architecture'
316 def detect_kernel_version(fname):
317 with open(fname, 'r') as f:
318 ver_pattern = re.compile("# Linux/.* Kernel Configuration")
319 for line in f.readlines():
320 if ver_pattern.match(line):
324 ver_numbers = ver_str.split('.')
325 if len(ver_numbers) < 3 or not ver_numbers[0].isdigit() or not ver_numbers[1].isdigit():
326 msg = 'failed to parse the version "' + ver_str + '"'
328 return (int(ver_numbers[0]), int(ver_numbers[1])), None
329 return None, 'no kernel version detected'
332 def detect_compiler(fname):
335 with open(fname, 'r') as f:
336 gcc_version_pattern = re.compile("CONFIG_GCC_VERSION=[0-9]*")
337 clang_version_pattern = re.compile("CONFIG_CLANG_VERSION=[0-9]*")
338 for line in f.readlines():
339 if gcc_version_pattern.match(line):
340 gcc_version = line[19:-1]
341 if clang_version_pattern.match(line):
342 clang_version = line[21:-1]
343 if not gcc_version or not clang_version:
344 return None, 'no CONFIG_GCC_VERSION or CONFIG_CLANG_VERSION'
345 if gcc_version == '0' and clang_version != '0':
346 return 'CLANG ' + clang_version, 'OK'
347 if gcc_version != '0' and clang_version == '0':
348 return 'GCC ' + gcc_version, 'OK'
349 sys.exit('[!] ERROR: invalid GCC_VERSION and CLANG_VERSION: {} {}'.format(gcc_version, clang_version))
352 def add_kconfig_checks(l, arch):
353 # Calling the KconfigCheck class constructor:
354 # KconfigCheck(reason, decision, name, expected)
356 # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
357 # when the tool doesn't check the cmdline.
359 efi_not_set = KconfigCheck('-', '-', 'EFI', 'is not set')
360 cc_is_gcc = KconfigCheck('-', '-', 'CC_IS_GCC', 'y') # exists since v4.18
361 cc_is_clang = KconfigCheck('-', '-', 'CC_IS_CLANG', 'y') # exists since v4.18
363 modules_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'MODULES', 'is not set')
364 devmem_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'DEVMEM', 'is not set') # refers to LOCKDOWN
365 bpf_syscall_not_set = KconfigCheck('cut_attack_surface', 'lockdown', 'BPF_SYSCALL', 'is not set') # refers to LOCKDOWN
367 # 'self_protection', 'defconfig'
368 l += [KconfigCheck('self_protection', 'defconfig', 'BUG', 'y')]
369 l += [KconfigCheck('self_protection', 'defconfig', 'SLUB_DEBUG', 'y')]
370 l += [KconfigCheck('self_protection', 'defconfig', 'THREAD_INFO_IN_TASK', 'y')]
371 gcc_plugins_support_is_set = KconfigCheck('self_protection', 'defconfig', 'GCC_PLUGINS', 'y')
372 l += [gcc_plugins_support_is_set]
373 iommu_support_is_set = KconfigCheck('self_protection', 'defconfig', 'IOMMU_SUPPORT', 'y')
374 l += [iommu_support_is_set] # is needed for mitigating DMA attacks
375 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR', 'y'),
376 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR', 'y'),
377 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_REGULAR', 'y'),
378 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_AUTO', 'y'),
379 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
380 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_STRONG', 'y'),
381 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
382 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_KERNEL_RWX', 'y'),
383 KconfigCheck('self_protection', 'defconfig', 'DEBUG_RODATA', 'y'))] # before v4.11
384 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_MODULE_RWX', 'y'),
385 KconfigCheck('self_protection', 'defconfig', 'DEBUG_SET_MODULE_RONX', 'y'),
386 modules_not_set)] # DEBUG_SET_MODULE_RONX was before v4.11
387 l += [OR(KconfigCheck('self_protection', 'defconfig', 'REFCOUNT_FULL', 'y'),
388 VersionCheck((5, 5)))] # REFCOUNT_FULL is enabled by default since v5.5
389 if arch in ('X86_64', 'ARM64', 'X86_32'):
390 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y')]
391 if arch in ('X86_64', 'ARM64'):
392 l += [KconfigCheck('self_protection', 'defconfig', 'VMAP_STACK', 'y')]
393 if arch in ('X86_64', 'X86_32'):
394 l += [KconfigCheck('self_protection', 'defconfig', 'X86_MCE', 'y')]
395 l += [KconfigCheck('self_protection', 'defconfig', 'X86_MCE_INTEL', 'y')]
396 l += [KconfigCheck('self_protection', 'defconfig', 'X86_MCE_AMD', 'y')]
397 l += [KconfigCheck('self_protection', 'defconfig', 'MICROCODE', 'y')] # is needed for mitigating CPU bugs
398 l += [KconfigCheck('self_protection', 'defconfig', 'RETPOLINE', 'y')]
399 l += [KconfigCheck('self_protection', 'defconfig', 'SYN_COOKIES', 'y')] # another reason?
400 l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_SMAP', 'y'),
401 VersionCheck((5, 19)))] # X86_SMAP is enabled by default since v5.19
402 l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_UMIP', 'y'),
403 KconfigCheck('self_protection', 'defconfig', 'X86_INTEL_UMIP', 'y'))]
404 if arch in ('ARM64', 'ARM'):
405 l += [KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_PER_TASK', 'y')]
407 l += [KconfigCheck('self_protection', 'defconfig', 'PAGE_TABLE_ISOLATION', 'y')]
408 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MEMORY', 'y')]
409 l += [AND(KconfigCheck('self_protection', 'defconfig', 'INTEL_IOMMU', 'y'),
410 iommu_support_is_set)]
411 l += [AND(KconfigCheck('self_protection', 'defconfig', 'AMD_IOMMU', 'y'),
412 iommu_support_is_set)]
414 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PAN', 'y')]
415 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_EPAN', 'y')]
416 l += [KconfigCheck('self_protection', 'defconfig', 'UNMAP_KERNEL_AT_EL0', 'y')]
417 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_E0PD', 'y')]
418 l += [KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y')]
419 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PTR_AUTH_KERNEL', 'y')]
420 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_BTI_KERNEL', 'y')]
421 l += [KconfigCheck('self_protection', 'defconfig', 'MITIGATE_SPECTRE_BRANCH_HISTORY', 'y')]
422 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_MTE', 'y')]
423 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MODULE_REGION_FULL', 'y')]
424 l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_EL2_VECTORS', 'y'),
425 AND(KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y'),
426 VersionCheck((5, 9))))] # HARDEN_EL2_VECTORS was included in RANDOMIZE_BASE in v5.9
427 l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y'),
428 VersionCheck((5, 10)))] # HARDEN_BRANCH_PREDICTOR is enabled by default since v5.10
430 l += [KconfigCheck('self_protection', 'defconfig', 'CPU_SW_DOMAIN_PAN', 'y')]
431 l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y')]
432 l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_HISTORY', 'y')]
434 # 'self_protection', 'kspp'
435 l += [KconfigCheck('self_protection', 'kspp', 'BUG_ON_DATA_CORRUPTION', 'y')]
436 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_WX', 'y')]
437 l += [KconfigCheck('self_protection', 'kspp', 'SCHED_STACK_END_CHECK', 'y')]
438 l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_HARDENED', 'y')]
439 l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_RANDOM', 'y')]
440 l += [KconfigCheck('self_protection', 'kspp', 'SHUFFLE_PAGE_ALLOCATOR', 'y')]
441 l += [KconfigCheck('self_protection', 'kspp', 'FORTIFY_SOURCE', 'y')]
442 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_LIST', 'y')]
443 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_VIRTUAL', 'y')]
444 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_SG', 'y')]
445 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_CREDENTIALS', 'y')]
446 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_NOTIFIERS', 'y')]
447 l += [KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y')]
448 l += [KconfigCheck('self_protection', 'kspp', 'KFENCE', 'y')]
449 l += [KconfigCheck('self_protection', 'kspp', 'WERROR', 'y')]
450 l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y')]
451 l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set')] # true if IOMMU_DEFAULT_DMA_STRICT is set
452 l += [KconfigCheck('self_protection', 'kspp', 'ZERO_CALL_USED_REGS', 'y')]
453 l += [KconfigCheck('self_protection', 'kspp', 'HW_RANDOM_TPM', 'y')]
454 l += [KconfigCheck('self_protection', 'kspp', 'STATIC_USERMODEHELPER', 'y')] # needs userspace support
455 l += [KconfigCheck('self_protection', 'kspp', 'SCHED_CORE', 'y')]
456 randstruct_is_set = OR(KconfigCheck('self_protection', 'kspp', 'RANDSTRUCT_FULL', 'y'),
457 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_RANDSTRUCT', 'y'))
458 l += [randstruct_is_set]
459 l += [AND(KconfigCheck('self_protection', 'kspp', 'RANDSTRUCT_PERFORMANCE', 'is not set'),
460 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_RANDSTRUCT_PERFORMANCE', 'is not set'),
462 hardened_usercopy_is_set = KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y')
463 l += [hardened_usercopy_is_set]
464 l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
465 hardened_usercopy_is_set)]
466 l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_PAGESPAN', 'is not set'),
467 hardened_usercopy_is_set)]
468 l += [AND(KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_LATENT_ENTROPY', 'y'),
469 gcc_plugins_support_is_set)]
470 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG', 'y'),
472 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_ALL', 'y'),
474 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_SHA512', 'y'),
476 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_FORCE', 'y'),
477 modules_not_set)] # refers to LOCKDOWN
478 l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_STACK_ALL_ZERO', 'y'),
479 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STRUCTLEAK_BYREF_ALL', 'y'))]
480 l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
481 KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'))]
482 # CONFIG_INIT_ON_FREE_DEFAULT_ON was added in v5.3.
483 # CONFIG_PAGE_POISONING_ZERO was removed in v5.11.
484 # Starting from v5.11 CONFIG_PAGE_POISONING unconditionally checks
485 # the 0xAA poison pattern on allocation.
486 # That brings higher performance penalty.
487 l += [OR(KconfigCheck('self_protection', 'kspp', 'EFI_DISABLE_PCI_DMA', 'y'),
489 l += [OR(KconfigCheck('self_protection', 'kspp', 'RESET_ATTACK_MITIGATION', 'y'),
490 efi_not_set)] # needs userspace support (systemd)
491 ubsan_bounds_is_set = KconfigCheck('self_protection', 'kspp', 'UBSAN_BOUNDS', 'y')
492 l += [ubsan_bounds_is_set]
493 l += [OR(KconfigCheck('self_protection', 'kspp', 'UBSAN_LOCAL_BOUNDS', 'y'),
494 AND(ubsan_bounds_is_set,
496 l += [AND(KconfigCheck('self_protection', 'kspp', 'UBSAN_TRAP', 'y'),
498 KconfigCheck('self_protection', 'kspp', 'UBSAN_SHIFT', 'is not set'),
499 KconfigCheck('self_protection', 'kspp', 'UBSAN_DIV_ZERO', 'is not set'),
500 KconfigCheck('self_protection', 'kspp', 'UBSAN_UNREACHABLE', 'is not set'),
501 KconfigCheck('self_protection', 'kspp', 'UBSAN_BOOL', 'is not set'),
502 KconfigCheck('self_protection', 'kspp', 'UBSAN_ENUM', 'is not set'),
503 KconfigCheck('self_protection', 'kspp', 'UBSAN_ALIGNMENT', 'is not set'))] # only array index bounds checking with traps
504 if arch in ('X86_64', 'ARM64', 'X86_32'):
505 l += [AND(KconfigCheck('self_protection', 'kspp', 'UBSAN_SANITIZE_ALL', 'y'),
506 ubsan_bounds_is_set)] # ARCH_HAS_UBSAN_SANITIZE_ALL is not enabled for ARM
507 stackleak_is_set = KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STACKLEAK', 'y')
508 l += [AND(stackleak_is_set, gcc_plugins_support_is_set)]
509 l += [AND(KconfigCheck('self_protection', 'kspp', 'STACKLEAK_METRICS', 'is not set'),
511 gcc_plugins_support_is_set)]
512 l += [AND(KconfigCheck('self_protection', 'kspp', 'STACKLEAK_RUNTIME_DISABLE', 'is not set'),
514 gcc_plugins_support_is_set)]
515 l += [KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y')]
516 if arch in ('X86_64', 'ARM64'):
517 cfi_clang_is_set = KconfigCheck('self_protection', 'kspp', 'CFI_CLANG', 'y')
518 l += [cfi_clang_is_set]
519 l += [AND(KconfigCheck('self_protection', 'kspp', 'CFI_PERMISSIVE', 'is not set'),
521 if arch in ('X86_64', 'X86_32'):
522 l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '65536')]
523 l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU_DEFAULT_ON', 'y'),
524 iommu_support_is_set)]
525 if arch in ('ARM64', 'ARM'):
526 l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '32768')]
527 l += [KconfigCheck('self_protection', 'kspp', 'SYN_COOKIES', 'y')] # another reason?
529 l += [KconfigCheck('self_protection', 'kspp', 'SLS', 'y')] # vs CVE-2021-26341 in Straight-Line-Speculation
530 l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU_SVM', 'y'),
531 iommu_support_is_set)]
532 l += [AND(KconfigCheck('self_protection', 'kspp', 'AMD_IOMMU_V2', 'y'),
533 iommu_support_is_set)]
535 l += [KconfigCheck('self_protection', 'kspp', 'ARM64_SW_TTBR0_PAN', 'y')]
536 l += [KconfigCheck('self_protection', 'kspp', 'SHADOW_CALL_STACK', 'y')]
537 l += [KconfigCheck('self_protection', 'kspp', 'KASAN_HW_TAGS', 'y')]
539 l += [KconfigCheck('self_protection', 'kspp', 'PAGE_TABLE_ISOLATION', 'y')]
540 l += [KconfigCheck('self_protection', 'kspp', 'HIGHMEM64G', 'y')]
541 l += [KconfigCheck('self_protection', 'kspp', 'X86_PAE', 'y')]
542 l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU', 'y'),
543 iommu_support_is_set)]
545 # 'self_protection', 'clipos'
546 l += [KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set')]
549 if arch in ('X86_64', 'ARM64', 'X86_32'):
550 l += [KconfigCheck('security_policy', 'defconfig', 'SECURITY', 'y')] # and choose your favourite LSM
552 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY', 'y')] # and choose your favourite LSM
553 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_YAMA', 'y')]
554 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LANDLOCK', 'y')]
555 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_DISABLE', 'is not set')]
556 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_BOOTPARAM', 'is not set')]
557 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_DEVELOP', 'is not set')]
558 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LOCKDOWN_LSM', 'y')]
559 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LOCKDOWN_LSM_EARLY', 'y')]
560 l += [KconfigCheck('security_policy', 'kspp', 'LOCK_DOWN_KERNEL_FORCE_CONFIDENTIALITY', 'y')]
561 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_WRITABLE_HOOKS', 'is not set')] # refers to SECURITY_SELINUX_DISABLE
563 # 'cut_attack_surface', 'defconfig'
564 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP', 'y')]
565 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP_FILTER', 'y')]
566 l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'BPF_UNPRIV_DEFAULT_OFF', 'y'),
567 bpf_syscall_not_set)] # see unprivileged_bpf_disabled
568 if arch in ('X86_64', 'ARM64', 'X86_32'):
569 l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'STRICT_DEVMEM', 'y'),
570 devmem_not_set)] # refers to LOCKDOWN
572 # 'cut_attack_surface', 'kspp'
573 l += [KconfigCheck('cut_attack_surface', 'kspp', 'SECURITY_DMESG_RESTRICT', 'y')]
574 l += [KconfigCheck('cut_attack_surface', 'kspp', 'ACPI_CUSTOM_METHOD', 'is not set')] # refers to LOCKDOWN
575 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_BRK', 'is not set')]
576 l += [KconfigCheck('cut_attack_surface', 'kspp', 'DEVKMEM', 'is not set')] # refers to LOCKDOWN
577 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_VDSO', 'is not set')]
578 l += [KconfigCheck('cut_attack_surface', 'kspp', 'BINFMT_MISC', 'is not set')]
579 l += [KconfigCheck('cut_attack_surface', 'kspp', 'INET_DIAG', 'is not set')]
580 l += [KconfigCheck('cut_attack_surface', 'kspp', 'KEXEC', 'is not set')] # refers to LOCKDOWN
581 l += [KconfigCheck('cut_attack_surface', 'kspp', 'PROC_KCORE', 'is not set')] # refers to LOCKDOWN
582 l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_PTYS', 'is not set')]
583 l += [KconfigCheck('cut_attack_surface', 'kspp', 'HIBERNATION', 'is not set')] # refers to LOCKDOWN
584 l += [KconfigCheck('cut_attack_surface', 'kspp', 'IA32_EMULATION', 'is not set')]
585 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_X32', 'is not set')]
586 l += [KconfigCheck('cut_attack_surface', 'kspp', 'MODIFY_LDT_SYSCALL', 'is not set')]
587 l += [KconfigCheck('cut_attack_surface', 'kspp', 'OABI_COMPAT', 'is not set')]
588 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_MSR', 'is not set')] # refers to LOCKDOWN
589 l += [modules_not_set]
590 l += [devmem_not_set]
591 l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'IO_STRICT_DEVMEM', 'y'),
592 devmem_not_set)] # refers to LOCKDOWN
593 l += [AND(KconfigCheck('cut_attack_surface', 'kspp', 'LDISC_AUTOLOAD', 'is not set'),
594 KconfigCheck('cut_attack_surface', 'kspp', 'LDISC_AUTOLOAD', 'is present'))]
596 l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y')] # 'vsyscall=none'
598 l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'STRICT_DEVMEM', 'y'),
599 devmem_not_set)] # refers to LOCKDOWN
601 # 'cut_attack_surface', 'grsec'
602 l += [KconfigCheck('cut_attack_surface', 'grsec', 'ZSMALLOC_STAT', 'is not set')]
603 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PAGE_OWNER', 'is not set')]
604 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_KMEMLEAK', 'is not set')]
605 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BINFMT_AOUT', 'is not set')]
606 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KPROBE_EVENTS', 'is not set')]
607 l += [KconfigCheck('cut_attack_surface', 'grsec', 'UPROBE_EVENTS', 'is not set')]
608 l += [KconfigCheck('cut_attack_surface', 'grsec', 'GENERIC_TRACER', 'is not set')] # refers to LOCKDOWN
609 l += [KconfigCheck('cut_attack_surface', 'grsec', 'FUNCTION_TRACER', 'is not set')]
610 l += [KconfigCheck('cut_attack_surface', 'grsec', 'STACK_TRACER', 'is not set')]
611 l += [KconfigCheck('cut_attack_surface', 'grsec', 'HIST_TRIGGERS', 'is not set')]
612 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BLK_DEV_IO_TRACE', 'is not set')]
613 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_VMCORE', 'is not set')]
614 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_PAGE_MONITOR', 'is not set')]
615 l += [KconfigCheck('cut_attack_surface', 'grsec', 'USELIB', 'is not set')]
616 l += [KconfigCheck('cut_attack_surface', 'grsec', 'CHECKPOINT_RESTORE', 'is not set')]
617 l += [KconfigCheck('cut_attack_surface', 'grsec', 'USERFAULTFD', 'is not set')]
618 l += [KconfigCheck('cut_attack_surface', 'grsec', 'HWPOISON_INJECT', 'is not set')]
619 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MEM_SOFT_DIRTY', 'is not set')]
620 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEVPORT', 'is not set')] # refers to LOCKDOWN
621 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set')] # refers to LOCKDOWN
622 l += [KconfigCheck('cut_attack_surface', 'grsec', 'NOTIFIER_ERROR_INJECTION', 'is not set')]
623 l += [KconfigCheck('cut_attack_surface', 'grsec', 'FAIL_FUTEX', 'is not set')]
624 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PUNIT_ATOM_DEBUG', 'is not set')]
625 l += [KconfigCheck('cut_attack_surface', 'grsec', 'ACPI_CONFIGFS', 'is not set')]
626 l += [KconfigCheck('cut_attack_surface', 'grsec', 'EDAC_DEBUG', 'is not set')]
627 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DRM_I915_DEBUG', 'is not set')]
628 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BCACHE_CLOSURES_DEBUG', 'is not set')]
629 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DVB_C8SECTPFE', 'is not set')]
630 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_SLRAM', 'is not set')]
631 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_PHRAM', 'is not set')]
632 l += [KconfigCheck('cut_attack_surface', 'grsec', 'IO_URING', 'is not set')]
633 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCMP', 'is not set')]
634 l += [KconfigCheck('cut_attack_surface', 'grsec', 'RSEQ', 'is not set')]
635 l += [KconfigCheck('cut_attack_surface', 'grsec', 'LATENCYTOP', 'is not set')]
636 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCOV', 'is not set')]
637 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROVIDE_OHCI1394_DMA_INIT', 'is not set')]
638 l += [KconfigCheck('cut_attack_surface', 'grsec', 'SUNRPC_DEBUG', 'is not set')]
639 l += [AND(KconfigCheck('cut_attack_surface', 'grsec', 'PTDUMP_DEBUGFS', 'is not set'),
640 KconfigCheck('cut_attack_surface', 'grsec', 'X86_PTDUMP', 'is not set'))]
642 # 'cut_attack_surface', 'maintainer'
643 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'DRM_LEGACY', 'is not set')] # recommended by Daniel Vetter in /issues/38
644 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'FB', 'is not set')] # recommended by Daniel Vetter in /issues/38
645 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'VT', 'is not set')] # recommended by Daniel Vetter in /issues/38
646 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD', 'is not set')] # recommended by Denis Efremov in /pull/54
647 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD_RAWCMD', 'is not set')] # recommended by Denis Efremov in /pull/62
649 # 'cut_attack_surface', 'grapheneos'
650 l += [KconfigCheck('cut_attack_surface', 'grapheneos', 'AIO', 'is not set')]
652 # 'cut_attack_surface', 'clipos'
653 l += [KconfigCheck('cut_attack_surface', 'clipos', 'STAGING', 'is not set')]
654 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KSM', 'is not set')] # to prevent FLUSH+RELOAD attack
655 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KALLSYMS', 'is not set')]
656 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_VSYSCALL_EMULATION', 'is not set')]
657 l += [KconfigCheck('cut_attack_surface', 'clipos', 'MAGIC_SYSRQ', 'is not set')]
658 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KEXEC_FILE', 'is not set')] # refers to LOCKDOWN (permissive)
659 l += [KconfigCheck('cut_attack_surface', 'clipos', 'USER_NS', 'is not set')] # user.max_user_namespaces=0
660 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_CPUID', 'is not set')]
661 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_IOPL_IOPERM', 'is not set')] # refers to LOCKDOWN
662 l += [KconfigCheck('cut_attack_surface', 'clipos', 'ACPI_TABLE_UPGRADE', 'is not set')] # refers to LOCKDOWN
663 l += [KconfigCheck('cut_attack_surface', 'clipos', 'EFI_CUSTOM_SSDT_OVERLAYS', 'is not set')]
664 l += [KconfigCheck('cut_attack_surface', 'clipos', 'COREDUMP', 'is not set')] # cut userspace attack surface
665 # l += [KconfigCheck('cut_attack_surface', 'clipos', 'IKCONFIG', 'is not set')] # no, IKCONFIG is needed for this check :)
666 if arch in ('X86_64', 'X86_32'):
667 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_INTEL_TSX_MODE_OFF', 'y')] # tsx=off
669 # 'cut_attack_surface', 'lockdown'
670 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'EFI_TEST', 'is not set')] # refers to LOCKDOWN
671 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'MMIOTRACE_TEST', 'is not set')] # refers to LOCKDOWN
672 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'KPROBES', 'is not set')] # refers to LOCKDOWN
673 l += [bpf_syscall_not_set] # refers to LOCKDOWN
675 # 'cut_attack_surface', 'my'
676 l += [KconfigCheck('cut_attack_surface', 'my', 'MMIOTRACE', 'is not set')] # refers to LOCKDOWN (permissive)
677 l += [KconfigCheck('cut_attack_surface', 'my', 'LIVEPATCH', 'is not set')]
678 l += [KconfigCheck('cut_attack_surface', 'my', 'IP_DCCP', 'is not set')]
679 l += [KconfigCheck('cut_attack_surface', 'my', 'IP_SCTP', 'is not set')]
680 l += [KconfigCheck('cut_attack_surface', 'my', 'FTRACE', 'is not set')] # refers to LOCKDOWN
681 l += [KconfigCheck('cut_attack_surface', 'my', 'VIDEO_VIVID', 'is not set')]
682 l += [KconfigCheck('cut_attack_surface', 'my', 'INPUT_EVBUG', 'is not set')] # Can be used as a keylogger
683 l += [KconfigCheck('cut_attack_surface', 'my', 'KGDB', 'is not set')]
684 l += [OR(KconfigCheck('cut_attack_surface', 'my', 'TRIM_UNUSED_KSYMS', 'y'),
688 if arch in ('X86_64', 'ARM64', 'X86_32'):
689 l += [KconfigCheck('harden_userspace', 'defconfig', 'INTEGRITY', 'y')]
691 l += [KconfigCheck('harden_userspace', 'my', 'INTEGRITY', 'y')]
693 l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_PTR_AUTH', 'y')]
694 l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_BTI', 'y')]
695 if arch in ('ARM', 'X86_32'):
696 l += [KconfigCheck('harden_userspace', 'defconfig', 'VMSPLIT_3G', 'y')]
697 if arch in ('X86_64', 'ARM64'):
698 l += [KconfigCheck('harden_userspace', 'clipos', 'ARCH_MMAP_RND_BITS', '32')]
699 if arch in ('X86_32', 'ARM'):
700 l += [KconfigCheck('harden_userspace', 'my', 'ARCH_MMAP_RND_BITS', '16')]
703 def add_cmdline_checks(l, arch):
704 # Calling the CmdlineCheck class constructor:
705 # CmdlineCheck(reason, decision, name, expected)
707 # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
708 # when the tool doesn't check the cmdline.
710 # [!] Make sure that values of the options in CmdlineChecks need normalization.
711 # For more info see normalize_cmdline_options().
713 # A common pattern for checking the 'param_x' cmdline parameter
714 # that __overrides__ the 'PARAM_X_DEFAULT' kconfig option:
715 # l += [OR(CmdlineCheck(reason, decision, 'param_x', '1'),
716 # AND(KconfigCheck(reason, decision, 'PARAM_X_DEFAULT_ON', 'y'),
717 # CmdlineCheck(reason, decision, 'param_x, 'is not set')))]
719 # Here we don't check the kconfig options or minimal kernel version
720 # required for the cmdline parameters. That would make the checks
721 # very complex and not give a 100% guarantee anyway.
723 # 'self_protection', 'defconfig'
724 l += [CmdlineCheck('self_protection', 'defconfig', 'nosmep', 'is not set')]
725 l += [CmdlineCheck('self_protection', 'defconfig', 'nosmap', 'is not set')]
726 l += [CmdlineCheck('self_protection', 'defconfig', 'nokaslr', 'is not set')]
727 l += [CmdlineCheck('self_protection', 'defconfig', 'nopti', 'is not set')]
728 l += [CmdlineCheck('self_protection', 'defconfig', 'nospectre_v1', 'is not set')]
729 l += [CmdlineCheck('self_protection', 'defconfig', 'nospectre_v2', 'is not set')]
730 l += [CmdlineCheck('self_protection', 'defconfig', 'nospec_store_bypass_disable', 'is not set')]
731 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'mitigations', 'is not off'),
732 CmdlineCheck('self_protection', 'defconfig', 'mitigations', 'is not set'))]
733 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'spectre_v2', 'is not off'),
734 CmdlineCheck('self_protection', 'defconfig', 'spectre_v2', 'is not set'))]
735 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'spectre_v2_user', 'is not off'),
736 CmdlineCheck('self_protection', 'defconfig', 'spectre_v2_user', 'is not set'))]
737 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'spec_store_bypass_disable', 'is not off'),
738 CmdlineCheck('self_protection', 'defconfig', 'spec_store_bypass_disable', 'is not set'))]
739 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'l1tf', 'is not off'),
740 CmdlineCheck('self_protection', 'defconfig', 'l1tf', 'is not set'))]
741 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'mds', 'is not off'),
742 CmdlineCheck('self_protection', 'defconfig', 'mds', 'is not set'))]
743 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'tsx_async_abort', 'is not off'),
744 CmdlineCheck('self_protection', 'defconfig', 'tsx_async_abort', 'is not set'))]
745 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'srbds', 'is not off'),
746 CmdlineCheck('self_protection', 'defconfig', 'srbds', 'is not set'))]
747 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'mmio_stale_data', 'is not off'),
748 CmdlineCheck('self_protection', 'defconfig', 'mmio_stale_data', 'is not set'))]
749 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'retbleed', 'is not off'),
750 CmdlineCheck('self_protection', 'defconfig', 'retbleed', 'is not set'))]
752 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'ssbd', 'kernel'),
753 CmdlineCheck('self_protection', 'my', 'ssbd', 'force-on'),
754 CmdlineCheck('self_protection', 'defconfig', 'ssbd', 'is not set'))]
755 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', 'full'),
756 AND(KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y'),
757 CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set')))]
759 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', '1'),
760 CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set'))]
762 # 'self_protection', 'kspp'
763 l += [CmdlineCheck('self_protection', 'kspp', 'nosmt', 'is present')]
764 l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', '1'),
765 AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y'),
766 CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', 'is not set')))]
767 l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_free', '1'),
768 AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
769 CmdlineCheck('self_protection', 'kspp', 'init_on_free', 'is not set')),
770 AND(CmdlineCheck('self_protection', 'kspp', 'page_poison', '1'),
771 KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'),
772 CmdlineCheck('self_protection', 'kspp', 'slub_debug', 'P')))]
773 l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_nomerge', 'is present'),
774 AND(KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set'),
775 CmdlineCheck('self_protection', 'kspp', 'slab_merge', 'is not set')))]
776 l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.strict', '1'),
777 AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y'),
778 CmdlineCheck('self_protection', 'kspp', 'iommu.strict', 'is not set')))]
779 l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', '0'),
780 AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set'),
781 CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', 'is not set')))]
782 # The cmdline checks compatible with the kconfig recommendations of the KSPP project...
783 l += [OR(CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', '1'),
784 AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y'),
785 CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', 'is not set')))]
786 l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', '0'),
787 AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
788 CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', 'is not set')))]
790 if arch in ('X86_64', 'ARM64', 'X86_32'):
791 l += [OR(CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', '1'),
792 AND(KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y'),
793 CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', 'is not set')))]
794 if arch in ('X86_64', 'X86_32'):
795 l += [AND(CmdlineCheck('self_protection', 'kspp', 'pti', 'on'),
796 CmdlineCheck('self_protection', 'defconfig', 'nopti', 'is not set'))]
798 # 'self_protection', 'clipos'
799 l += [CmdlineCheck('self_protection', 'clipos', 'page_alloc.shuffle', '1')]
801 # 'cut_attack_surface', 'kspp'
803 l += [OR(CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'none'),
804 AND(KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y'),
805 CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'is not set')))]
807 # 'cut_attack_surface', 'grsec'
808 # The cmdline checks compatible with the kconfig options disabled by grsecurity...
809 l += [OR(CmdlineCheck('cut_attack_surface', 'grsec', 'debugfs', 'off'),
810 KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set'))] # ... the end
812 # 'cut_attack_surface', 'my'
813 l += [CmdlineCheck('cut_attack_surface', 'my', 'sysrq_always_enabled', 'is not set')]
815 def print_unknown_options(checklist, parsed_options):
819 if o1.type != 'complex':
820 known_options.append(o1.name)
823 if o2.type != 'complex':
824 if hasattr(o2, 'name'):
825 known_options.append(o2.name)
828 assert(o3.type != 'complex'), \
829 'unexpected ComplexOptCheck inside {}'.format(o2.name)
830 if hasattr(o3, 'name'):
831 known_options.append(o3.name)
833 for option, value in parsed_options.items():
834 if option not in known_options:
835 print('[?] No check for option {} ({})'.format(option, value))
838 def print_checklist(mode, checklist, with_results):
842 output.append(o.json_dump(with_results))
843 print(json.dumps(output))
850 print('=' * sep_line_len)
851 print('{:^40}|{:^7}|{:^12}|{:^10}|{:^18}'.format('option name', 'type', 'desired val', 'decision', 'reason'), end='')
853 print('| {}'.format('check result'), end='')
855 print('=' * sep_line_len)
858 for opt in checklist:
860 if mode == 'show_ok':
861 if not opt.result.startswith('OK'):
863 if mode == 'show_fail':
864 if not opt.result.startswith('FAIL'):
866 opt.table_print(mode, with_results)
868 if mode == 'verbose':
869 print('-' * sep_line_len)
874 fail_count = len(list(filter(lambda opt: opt.result.startswith('FAIL'), checklist)))
876 ok_count = len(list(filter(lambda opt: opt.result.startswith('OK'), checklist)))
878 if mode == 'show_ok':
879 fail_suppressed = ' (suppressed in output)'
880 if mode == 'show_fail':
881 ok_suppressed = ' (suppressed in output)'
883 print('[+] Config check is finished: \'OK\' - {}{} / \'FAIL\' - {}{}'.format(ok_count, ok_suppressed, fail_count, fail_suppressed))
886 def populate_simple_opt_with_data(opt, data, data_type):
887 assert(opt.type != 'complex'), \
888 'unexpected ComplexOptCheck "{}"'.format(opt.name)
889 assert(opt.type in SIMPLE_OPTION_TYPES), \
890 'invalid opt type "{}"'.format(opt.type)
891 assert(data_type in SIMPLE_OPTION_TYPES), \
892 'invalid data type "{}"'.format(data_type)
894 if data_type != opt.type:
897 if data_type in ('kconfig', 'cmdline'):
898 opt.state = data.get(opt.name, None)
900 assert(data_type == 'version'), \
901 'unexpected data type "{}"'.format(data_type)
905 def populate_opt_with_data(opt, data, data_type):
906 if opt.type == 'complex':
908 if o.type == 'complex':
909 # Recursion for nested ComplexOptCheck objects
910 populate_opt_with_data(o, data, data_type)
912 populate_simple_opt_with_data(o, data, data_type)
914 assert(opt.type in ('kconfig', 'cmdline')), \
915 'bad type "{}" for a simple check'.format(opt.type)
916 populate_simple_opt_with_data(opt, data, data_type)
919 def populate_with_data(checklist, data, data_type):
920 for opt in checklist:
921 populate_opt_with_data(opt, data, data_type)
924 def perform_checks(checklist):
925 for opt in checklist:
929 def parse_kconfig_file(parsed_options, fname):
930 with open(fname, 'r') as f:
931 opt_is_on = re.compile("CONFIG_[a-zA-Z0-9_]*=[a-zA-Z0-9_\"]*")
932 opt_is_off = re.compile("# CONFIG_[a-zA-Z0-9_]* is not set")
934 for line in f.readlines():
939 if opt_is_on.match(line):
940 option, value = line.split('=', 1)
941 if value == 'is not set':
942 sys.exit('[!] ERROR: bad enabled kconfig option "{}"'.format(line))
943 elif opt_is_off.match(line):
944 option, value = line[2:].split(' ', 1)
945 if value != 'is not set':
946 sys.exit('[!] ERROR: bad disabled kconfig option "{}"'.format(line))
948 if option in parsed_options:
949 sys.exit('[!] ERROR: kconfig option "{}" exists multiple times'.format(line))
952 parsed_options[option] = value
955 def normalize_cmdline_options(option, value):
956 # Don't normalize the cmdline option values if
957 # the Linux kernel doesn't use kstrtobool() for them
958 if option == 'debugfs':
959 # See debugfs_kernel() in fs/debugfs/inode.c
961 if option == 'mitigations':
962 # See mitigations_parse_cmdline() in kernel/cpu.c
965 # See pti_check_boottime_disable() in arch/x86/mm/pti.c
967 if option == 'spectre_v2':
968 # See spectre_v2_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
970 if option == 'spectre_v2_user':
971 # See spectre_v2_parse_user_cmdline() in arch/x86/kernel/cpu/bugs.c
973 if option == 'spec_store_bypass_disable':
974 # See ssb_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
977 # See l1tf_cmdline() in arch/x86/kernel/cpu/bugs.c
980 # See mds_cmdline() in arch/x86/kernel/cpu/bugs.c
982 if option == 'tsx_async_abort':
983 # See tsx_async_abort_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
985 if option == 'srbds':
986 # See srbds_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
988 if option == 'mmio_stale_data':
989 # See mmio_stale_data_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
991 if option == 'retbleed':
992 # See retbleed_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
995 # Implement a limited part of the kstrtobool() logic
996 if value in ('1', 'on', 'On', 'ON', 'y', 'Y', 'yes', 'Yes', 'YES'):
998 if value in ('0', 'off', 'Off', 'OFF', 'n', 'N', 'no', 'No', 'NO'):
1001 # Preserve unique values
1005 def parse_cmdline_file(parsed_options, fname):
1006 with open(fname, 'r') as f:
1012 sys.exit('[!] ERROR: more than one line in "{}"'.format(fname))
1016 name, value = opt.split('=', 1)
1019 value = '' # '' is not None
1020 value = normalize_cmdline_options(name, value)
1021 parsed_options[name] = value
1026 # * verbose mode for
1027 # - reporting about unknown kernel options in the kconfig
1028 # - verbose printing of ComplexOptCheck items
1029 # * json mode for printing the results in JSON format
1030 report_modes = ['verbose', 'json', 'show_ok', 'show_fail']
1031 supported_archs = ['X86_64', 'X86_32', 'ARM64', 'ARM']
1032 parser = ArgumentParser(prog='kconfig-hardened-check',
1033 description='A tool for checking the security hardening options of the Linux kernel')
1034 parser.add_argument('--version', action='version', version='%(prog)s ' + __version__)
1035 parser.add_argument('-p', '--print', choices=supported_archs,
1036 help='print security hardening preferences for the selected architecture')
1037 parser.add_argument('-c', '--config',
1038 help='check the kernel kconfig file against these preferences')
1039 parser.add_argument('-l', '--cmdline',
1040 help='check the kernel cmdline file against these preferences')
1041 parser.add_argument('-m', '--mode', choices=report_modes,
1042 help='choose the report mode')
1043 args = parser.parse_args()
1049 print('[+] Special report mode: {}'.format(mode))
1051 config_checklist = []
1055 sys.exit('[!] ERROR: --config and --print can\'t be used together')
1058 print('[+] Kconfig file to check: {}'.format(args.config))
1060 print('[+] Kernel cmdline file to check: {}'.format(args.cmdline))
1062 arch, msg = detect_arch(args.config, supported_archs)
1064 sys.exit('[!] ERROR: {}'.format(msg))
1066 print('[+] Detected architecture: {}'.format(arch))
1068 kernel_version, msg = detect_kernel_version(args.config)
1069 if not kernel_version:
1070 sys.exit('[!] ERROR: {}'.format(msg))
1072 print('[+] Detected kernel version: {}.{}'.format(kernel_version[0], kernel_version[1]))
1074 compiler, msg = detect_compiler(args.config)
1077 print('[+] Detected compiler: {}'.format(compiler))
1079 print('[-] Can\'t detect the compiler: {}'.format(msg))
1081 # add relevant kconfig checks to the checklist
1082 add_kconfig_checks(config_checklist, arch)
1085 # add relevant cmdline checks to the checklist
1086 add_cmdline_checks(config_checklist, arch)
1088 # populate the checklist with the parsed kconfig data
1089 parsed_kconfig_options = OrderedDict()
1090 parse_kconfig_file(parsed_kconfig_options, args.config)
1091 populate_with_data(config_checklist, parsed_kconfig_options, 'kconfig')
1092 populate_with_data(config_checklist, kernel_version, 'version')
1095 # populate the checklist with the parsed kconfig data
1096 parsed_cmdline_options = OrderedDict()
1097 parse_cmdline_file(parsed_cmdline_options, args.cmdline)
1098 populate_with_data(config_checklist, parsed_cmdline_options, 'cmdline')
1100 # now everything is ready for performing the checks
1101 perform_checks(config_checklist)
1103 # finally print the results
1104 if mode == 'verbose':
1105 print_unknown_options(config_checklist, parsed_kconfig_options)
1106 print_checklist(mode, config_checklist, True)
1110 sys.exit('[!] ERROR: checking cmdline doesn\'t work without checking kconfig')
1113 if mode in ('show_ok', 'show_fail'):
1114 sys.exit('[!] ERROR: wrong mode "{}" for --print'.format(mode))
1116 add_kconfig_checks(config_checklist, arch)
1117 add_cmdline_checks(config_checklist, arch)
1119 print('[+] Printing kernel security hardening preferences for {}...'.format(arch))
1120 print_checklist(mode, config_checklist, False)