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:
20 # l1d_flush=on (a part of the l1tf option)
28 # sysrq_always_enabled
33 # Hardware tag-based KASAN with arm64 Memory Tagging Extension (MTE):
35 # kasan.stacktrace=off
38 # N.B. Hardening sysctls:
39 # kernel.kptr_restrict=2 (or 1?)
40 # kernel.dmesg_restrict=1 (also see the kconfig option)
41 # kernel.perf_event_paranoid=3
42 # kernel.kexec_load_disabled=1
43 # kernel.yama.ptrace_scope=3
44 # user.max_user_namespaces=0
45 # what about bpf_jit_enable?
46 # kernel.unprivileged_bpf_disabled=1
47 # net.core.bpf_jit_harden=2
48 # vm.unprivileged_userfaultfd=0
49 # (at first, it disabled unprivileged userfaultfd,
50 # and since v5.11 it enables unprivileged userfaultfd for user-mode only)
51 # vm.mmap_min_addr has a good value
52 # dev.tty.ldisc_autoload=0
53 # fs.protected_symlinks=1
54 # fs.protected_hardlinks=1
55 # fs.protected_fifos=2
56 # fs.protected_regular=2
58 # kernel.modules_disabled=1
59 # kernel.randomize_va_space = 2
62 # pylint: disable=missing-module-docstring,missing-class-docstring,missing-function-docstring
63 # pylint: disable=line-too-long,invalid-name,too-many-branches,too-many-statements
67 from argparse import ArgumentParser
68 from collections import OrderedDict
71 from .__about__ import __version__
73 SIMPLE_OPTION_TYPES = ('kconfig', 'version', 'cmdline')
76 def __init__(self, reason, decision, name, expected):
77 assert(name and name == name.strip() and len(name.split()) == 1), \
78 'invalid name "{}" for {}'.format(name, self.__class__.__name__)
81 assert(decision and decision == decision.strip() and len(decision.split()) == 1), \
82 'invalid decision "{}" for "{}" check'.format(decision, name)
83 self.decision = decision
85 assert(reason and reason == reason.strip() and len(reason.split()) == 1), \
86 'invalid reason "{}" for "{}" check'.format(reason, name)
89 assert(expected and expected == expected.strip()), \
90 'invalid expected value "{}" for "{}" check (1)'.format(expected, name)
91 val_len = len(expected.split())
93 assert(expected == 'is not set' or expected == 'is not off'), \
94 'invalid expected value "{}" for "{}" check (2)'.format(expected, name)
96 assert(expected == 'is present'), \
97 'invalid expected value "{}" for "{}" check (3)'.format(expected, name)
99 assert(val_len == 1), \
100 'invalid expected value "{}" for "{}" check (4)'.format(expected, name)
101 self.expected = expected
111 # handle the 'is present' check
112 if self.expected == 'is present':
113 if self.state is None:
114 self.result = 'FAIL: is not present'
116 self.result = 'OK: is present'
119 # handle the 'is not off' option check
120 if self.expected == 'is not off':
121 if self.state == 'off':
122 self.result = 'FAIL: is off'
123 elif self.state is None:
124 self.result = 'FAIL: is off, not found'
126 self.result = 'OK: is not off, "' + self.state + '"'
129 # handle the option value check
130 if self.expected == self.state:
132 elif self.state is None:
133 if self.expected == 'is not set':
134 self.result = 'OK: is not found'
136 self.result = 'FAIL: is not found'
138 self.result = 'FAIL: "' + self.state + '"'
140 def table_print(self, _mode, with_results):
141 print('{:<40}|{:^7}|{:^12}|{:^10}|{:^18}'.format(self.name, self.type, self.expected, self.decision, self.reason), end='')
143 print('| {}'.format(self.result), end='')
145 def json_dump(self, with_results):
146 dump = [self.name, self.type, self.expected, self.decision, self.reason]
148 dump.append(self.result)
152 class KconfigCheck(OptCheck):
153 def __init__(self, *args, **kwargs):
154 super().__init__(*args, **kwargs)
155 self.name = 'CONFIG_' + self.name
162 class CmdlineCheck(OptCheck):
169 def __init__(self, ver_expected):
170 assert(ver_expected and isinstance(ver_expected, tuple) and len(ver_expected) == 2), \
171 'invalid version "{}" for VersionCheck'.format(ver_expected)
172 self.ver_expected = ver_expected
181 if self.ver[0] > self.ver_expected[0]:
182 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
184 if self.ver[0] < self.ver_expected[0]:
185 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
187 if self.ver[1] >= self.ver_expected[1]:
188 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
190 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
192 def table_print(self, _mode, with_results):
193 ver_req = 'kernel version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
194 print('{:<91}'.format(ver_req), end='')
196 print('| {}'.format(self.result), end='')
199 class ComplexOptCheck:
200 def __init__(self, *opts):
203 'empty {} check'.format(self.__class__.__name__)
204 assert(len(self.opts) != 1), \
205 'useless {} check: {}'.format(self.__class__.__name__, opts)
206 assert(isinstance(opts[0], (KconfigCheck, CmdlineCheck))), \
207 'invalid {} check: {}'.format(self.__class__.__name__, opts)
216 return self.opts[0].name
220 return self.opts[0].expected
222 def table_print(self, mode, with_results):
223 if mode == 'verbose':
224 print(' {:87}'.format('<<< ' + self.__class__.__name__ + ' >>>'), end='')
226 print('| {}'.format(self.result), end='')
229 o.table_print(mode, with_results)
232 o.table_print(mode, False)
234 print('| {}'.format(self.result), end='')
236 def json_dump(self, with_results):
237 dump = self.opts[0].json_dump(False)
239 dump.append(self.result)
243 class OR(ComplexOptCheck):
244 # self.opts[0] is the option that this OR-check is about.
246 # OR(<X_is_hardened>, <X_is_disabled>)
247 # OR(<X_is_hardened>, <old_X_is_hardened>)
249 for i, opt in enumerate(self.opts):
251 if opt.result.startswith('OK'):
252 self.result = opt.result
253 # Add more info for additional checks:
255 if opt.result == 'OK':
256 self.result = 'OK: {} is "{}"'.format(opt.name, opt.expected)
257 elif opt.result == 'OK: is not found':
258 self.result = 'OK: {} is not found'.format(opt.name)
259 elif opt.result == 'OK: is present':
260 self.result = 'OK: {} is present'.format(opt.name)
261 elif opt.result.startswith('OK: is not off'):
262 self.result = 'OK: {} is not off'.format(opt.name)
264 # VersionCheck provides enough info
265 assert(opt.result.startswith('OK: version')), \
266 'unexpected OK description "{}"'.format(opt.result)
268 self.result = self.opts[0].result
271 class AND(ComplexOptCheck):
272 # self.opts[0] is the option that this AND-check is about.
274 # AND(<suboption>, <main_option>)
275 # Suboption is not checked if checking of the main_option is failed.
276 # AND(<X_is_disabled>, <old_X_is_disabled>)
278 for i, opt in reversed(list(enumerate(self.opts))):
281 self.result = opt.result
283 if not opt.result.startswith('OK'):
284 # This FAIL is caused by additional checks,
285 # and not by the main option that this AND-check is about.
286 # Describe the reason of the FAIL.
287 if opt.result.startswith('FAIL: \"') or opt.result == 'FAIL: is not found':
288 self.result = 'FAIL: {} is not "{}"'.format(opt.name, opt.expected)
289 elif opt.result == 'FAIL: is not present':
290 self.result = 'FAIL: {} is not present'.format(opt.name)
291 elif opt.result == 'FAIL: is off':
292 self.result = 'FAIL: {} is off'.format(opt.name)
293 elif opt.result == 'FAIL: is off, not found':
294 self.result = 'FAIL: {} is off, not found'.format(opt.name)
296 # VersionCheck provides enough info
297 self.result = opt.result
298 assert(opt.result.startswith('FAIL: version')), \
299 'unexpected FAIL description "{}"'.format(opt.result)
303 def detect_arch(fname, archs):
304 with open(fname, 'r') as f:
305 arch_pattern = re.compile("CONFIG_[a-zA-Z0-9_]*=y")
307 for line in f.readlines():
308 if arch_pattern.match(line):
309 option, _ = line[7:].split('=', 1)
314 return None, 'more than one supported architecture is detected'
316 return None, 'failed to detect architecture'
320 def detect_kernel_version(fname):
321 with open(fname, 'r') as f:
322 ver_pattern = re.compile("# Linux/.* Kernel Configuration")
323 for line in f.readlines():
324 if ver_pattern.match(line):
328 ver_numbers = ver_str.split('.')
329 if len(ver_numbers) < 3 or not ver_numbers[0].isdigit() or not ver_numbers[1].isdigit():
330 msg = 'failed to parse the version "' + ver_str + '"'
332 return (int(ver_numbers[0]), int(ver_numbers[1])), None
333 return None, 'no kernel version detected'
336 def detect_compiler(fname):
339 with open(fname, 'r') as f:
340 gcc_version_pattern = re.compile("CONFIG_GCC_VERSION=[0-9]*")
341 clang_version_pattern = re.compile("CONFIG_CLANG_VERSION=[0-9]*")
342 for line in f.readlines():
343 if gcc_version_pattern.match(line):
344 gcc_version = line[19:-1]
345 if clang_version_pattern.match(line):
346 clang_version = line[21:-1]
347 if not gcc_version or not clang_version:
348 return None, 'no CONFIG_GCC_VERSION or CONFIG_CLANG_VERSION'
349 if gcc_version == '0' and clang_version != '0':
350 return 'CLANG ' + clang_version, 'OK'
351 if gcc_version != '0' and clang_version == '0':
352 return 'GCC ' + gcc_version, 'OK'
353 sys.exit('[!] ERROR: invalid GCC_VERSION and CLANG_VERSION: {} {}'.format(gcc_version, clang_version))
356 def add_kconfig_checks(l, arch):
357 # Calling the KconfigCheck class constructor:
358 # KconfigCheck(reason, decision, name, expected)
360 # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
361 # when the tool doesn't check the cmdline.
363 efi_not_set = KconfigCheck('-', '-', 'EFI', 'is not set')
364 cc_is_gcc = KconfigCheck('-', '-', 'CC_IS_GCC', 'y') # exists since v4.18
365 cc_is_clang = KconfigCheck('-', '-', 'CC_IS_CLANG', 'y') # exists since v4.18
367 modules_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'MODULES', 'is not set')
368 devmem_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'DEVMEM', 'is not set') # refers to LOCKDOWN
369 bpf_syscall_not_set = KconfigCheck('cut_attack_surface', 'lockdown', 'BPF_SYSCALL', 'is not set') # refers to LOCKDOWN
371 # 'self_protection', 'defconfig'
372 l += [KconfigCheck('self_protection', 'defconfig', 'BUG', 'y')]
373 l += [KconfigCheck('self_protection', 'defconfig', 'SLUB_DEBUG', 'y')]
374 gcc_plugins_support_is_set = KconfigCheck('self_protection', 'defconfig', 'GCC_PLUGINS', 'y')
375 l += [gcc_plugins_support_is_set]
376 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR', 'y'),
377 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR', 'y'),
378 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_REGULAR', 'y'),
379 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_AUTO', 'y'),
380 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
381 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_STRONG', 'y'),
382 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
383 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_KERNEL_RWX', 'y'),
384 KconfigCheck('self_protection', 'defconfig', 'DEBUG_RODATA', 'y'))] # before v4.11
385 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_MODULE_RWX', 'y'),
386 KconfigCheck('self_protection', 'defconfig', 'DEBUG_SET_MODULE_RONX', 'y'),
387 modules_not_set)] # DEBUG_SET_MODULE_RONX was before v4.11
388 l += [OR(KconfigCheck('self_protection', 'defconfig', 'REFCOUNT_FULL', 'y'),
389 VersionCheck((5, 5)))] # REFCOUNT_FULL is enabled by default since v5.5
390 l += [KconfigCheck('self_protection', 'defconfig', 'THREAD_INFO_IN_TASK', 'y')]
391 iommu_support_is_set = KconfigCheck('self_protection', 'defconfig', 'IOMMU_SUPPORT', 'y')
392 l += [iommu_support_is_set] # is needed for mitigating DMA attacks
393 if arch in ('X86_64', 'ARM64', 'X86_32'):
394 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y')]
395 if arch in ('X86_64', 'ARM64'):
396 l += [KconfigCheck('self_protection', 'defconfig', 'VMAP_STACK', 'y')]
397 if arch in ('X86_64', 'X86_32'):
398 l += [KconfigCheck('self_protection', 'defconfig', 'X86_MCE', 'y')]
399 l += [KconfigCheck('self_protection', 'defconfig', 'X86_MCE_INTEL', 'y')]
400 l += [KconfigCheck('self_protection', 'defconfig', 'X86_MCE_AMD', 'y')]
401 l += [KconfigCheck('self_protection', 'defconfig', 'MICROCODE', 'y')] # is needed for mitigating CPU bugs
402 l += [KconfigCheck('self_protection', 'defconfig', 'RETPOLINE', 'y')]
403 l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_SMAP', 'y'),
404 VersionCheck((5, 19)))] # X86_SMAP is enabled by default since v5.19
405 l += [KconfigCheck('self_protection', 'defconfig', 'SYN_COOKIES', 'y')] # another reason?
406 l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_UMIP', 'y'),
407 KconfigCheck('self_protection', 'defconfig', 'X86_INTEL_UMIP', 'y'))]
408 if arch in ('ARM64', 'ARM'):
409 l += [KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_PER_TASK', 'y')]
411 l += [KconfigCheck('self_protection', 'defconfig', 'PAGE_TABLE_ISOLATION', 'y')]
412 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MEMORY', 'y')]
413 l += [AND(KconfigCheck('self_protection', 'defconfig', 'INTEL_IOMMU', 'y'),
414 iommu_support_is_set)]
415 l += [AND(KconfigCheck('self_protection', 'defconfig', 'AMD_IOMMU', 'y'),
416 iommu_support_is_set)]
418 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PAN', 'y')]
419 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_EPAN', 'y')]
420 l += [KconfigCheck('self_protection', 'defconfig', 'UNMAP_KERNEL_AT_EL0', 'y')]
421 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_E0PD', 'y')]
422 l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_EL2_VECTORS', 'y'),
423 AND(KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y'),
424 VersionCheck((5, 9))))] # HARDEN_EL2_VECTORS was included in RANDOMIZE_BASE in v5.9
425 l += [KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y')]
426 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PTR_AUTH_KERNEL', 'y')]
427 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_BTI_KERNEL', 'y')]
428 l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y'),
429 VersionCheck((5, 10)))] # HARDEN_BRANCH_PREDICTOR is enabled by default since v5.10
430 l += [KconfigCheck('self_protection', 'defconfig', 'MITIGATE_SPECTRE_BRANCH_HISTORY', 'y')]
431 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_MTE', 'y')]
432 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MODULE_REGION_FULL', 'y')]
434 l += [KconfigCheck('self_protection', 'defconfig', 'CPU_SW_DOMAIN_PAN', 'y')]
435 l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y')]
436 l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_HISTORY', 'y')]
438 # 'self_protection', 'kspp'
439 l += [KconfigCheck('self_protection', 'kspp', 'BUG_ON_DATA_CORRUPTION', 'y')]
440 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_WX', 'y')]
441 l += [KconfigCheck('self_protection', 'kspp', 'SCHED_STACK_END_CHECK', 'y')]
442 l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_HARDENED', 'y')]
443 l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_RANDOM', 'y')]
444 l += [KconfigCheck('self_protection', 'kspp', 'SHUFFLE_PAGE_ALLOCATOR', 'y')]
445 l += [KconfigCheck('self_protection', 'kspp', 'FORTIFY_SOURCE', 'y')]
446 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_LIST', 'y')]
447 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_VIRTUAL', 'y')]
448 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_SG', 'y')]
449 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_CREDENTIALS', 'y')]
450 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_NOTIFIERS', 'y')]
451 l += [KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y')]
452 l += [AND(KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_LATENT_ENTROPY', 'y'),
453 gcc_plugins_support_is_set)]
454 l += [KconfigCheck('self_protection', 'kspp', 'KFENCE', 'y')]
455 l += [KconfigCheck('self_protection', 'kspp', 'WERROR', 'y')]
456 l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y')]
457 l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set')] # true if IOMMU_DEFAULT_DMA_STRICT is set
458 l += [KconfigCheck('self_protection', 'kspp', 'ZERO_CALL_USED_REGS', 'y')]
459 l += [KconfigCheck('self_protection', 'kspp', 'HW_RANDOM_TPM', 'y')]
460 l += [KconfigCheck('self_protection', 'kspp', 'STATIC_USERMODEHELPER', 'y')] # needs userspace support
461 l += [KconfigCheck('self_protection', 'kspp', 'SCHED_CORE', 'y')]
462 randstruct_is_set = OR(KconfigCheck('self_protection', 'kspp', 'RANDSTRUCT_FULL', 'y'),
463 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_RANDSTRUCT', 'y'))
464 l += [randstruct_is_set]
465 l += [AND(KconfigCheck('self_protection', 'kspp', 'RANDSTRUCT_PERFORMANCE', 'is not set'),
466 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_RANDSTRUCT_PERFORMANCE', 'is not set'),
468 hardened_usercopy_is_set = KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y')
469 l += [hardened_usercopy_is_set]
470 l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
471 hardened_usercopy_is_set)]
472 l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_PAGESPAN', 'is not set'),
473 hardened_usercopy_is_set)]
474 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG', 'y'),
476 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_ALL', 'y'),
478 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_SHA512', 'y'),
480 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_FORCE', 'y'),
481 modules_not_set)] # refers to LOCKDOWN
482 l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_STACK_ALL_ZERO', 'y'),
483 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STRUCTLEAK_BYREF_ALL', 'y'))]
484 l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
485 KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'))]
486 # CONFIG_INIT_ON_FREE_DEFAULT_ON was added in v5.3.
487 # CONFIG_PAGE_POISONING_ZERO was removed in v5.11.
488 # Starting from v5.11 CONFIG_PAGE_POISONING unconditionally checks
489 # the 0xAA poison pattern on allocation.
490 # That brings higher performance penalty.
491 l += [OR(KconfigCheck('self_protection', 'kspp', 'EFI_DISABLE_PCI_DMA', 'y'),
493 l += [OR(KconfigCheck('self_protection', 'kspp', 'RESET_ATTACK_MITIGATION', 'y'),
494 efi_not_set)] # needs userspace support (systemd)
495 ubsan_bounds_is_set = KconfigCheck('self_protection', 'kspp', 'UBSAN_BOUNDS', 'y')
496 l += [ubsan_bounds_is_set]
497 l += [OR(KconfigCheck('self_protection', 'kspp', 'UBSAN_LOCAL_BOUNDS', 'y'),
498 AND(ubsan_bounds_is_set,
500 l += [AND(KconfigCheck('self_protection', 'kspp', 'UBSAN_TRAP', 'y'),
502 KconfigCheck('self_protection', 'kspp', 'UBSAN_SHIFT', 'is not set'),
503 KconfigCheck('self_protection', 'kspp', 'UBSAN_DIV_ZERO', 'is not set'),
504 KconfigCheck('self_protection', 'kspp', 'UBSAN_UNREACHABLE', 'is not set'),
505 KconfigCheck('self_protection', 'kspp', 'UBSAN_BOOL', 'is not set'),
506 KconfigCheck('self_protection', 'kspp', 'UBSAN_ENUM', 'is not set'),
507 KconfigCheck('self_protection', 'kspp', 'UBSAN_ALIGNMENT', 'is not set'))] # only array index bounds checking with traps
508 if arch in ('X86_64', 'ARM64', 'X86_32'):
509 l += [AND(KconfigCheck('self_protection', 'kspp', 'UBSAN_SANITIZE_ALL', 'y'),
510 ubsan_bounds_is_set)] # ARCH_HAS_UBSAN_SANITIZE_ALL is not enabled for ARM
511 stackleak_is_set = KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STACKLEAK', 'y')
512 l += [AND(stackleak_is_set, gcc_plugins_support_is_set)]
513 l += [AND(KconfigCheck('self_protection', 'kspp', 'STACKLEAK_METRICS', 'is not set'),
515 gcc_plugins_support_is_set)]
516 l += [AND(KconfigCheck('self_protection', 'kspp', 'STACKLEAK_RUNTIME_DISABLE', 'is not set'),
518 gcc_plugins_support_is_set)]
519 l += [KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y')]
520 if arch in ('X86_64', 'ARM64'):
521 cfi_clang_is_set = KconfigCheck('self_protection', 'kspp', 'CFI_CLANG', 'y')
522 l += [cfi_clang_is_set]
523 l += [AND(KconfigCheck('self_protection', 'kspp', 'CFI_PERMISSIVE', 'is not set'),
525 if arch in ('X86_64', 'X86_32'):
526 l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '65536')]
527 l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU_DEFAULT_ON', 'y'),
528 iommu_support_is_set)]
529 if arch in ('ARM64', 'ARM'):
530 l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '32768')]
531 l += [KconfigCheck('self_protection', 'kspp', 'SYN_COOKIES', 'y')] # another reason?
533 l += [KconfigCheck('self_protection', 'kspp', 'SLS', 'y')] # vs CVE-2021-26341 in Straight-Line-Speculation
534 l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU_SVM', 'y'),
535 iommu_support_is_set)]
536 l += [AND(KconfigCheck('self_protection', 'kspp', 'AMD_IOMMU_V2', 'y'),
537 iommu_support_is_set)]
539 l += [KconfigCheck('self_protection', 'kspp', 'ARM64_SW_TTBR0_PAN', 'y')]
540 l += [KconfigCheck('self_protection', 'kspp', 'SHADOW_CALL_STACK', 'y')]
541 l += [KconfigCheck('self_protection', 'kspp', 'KASAN_HW_TAGS', 'y')]
543 l += [KconfigCheck('self_protection', 'kspp', 'PAGE_TABLE_ISOLATION', 'y')]
544 l += [KconfigCheck('self_protection', 'kspp', 'HIGHMEM64G', 'y')]
545 l += [KconfigCheck('self_protection', 'kspp', 'X86_PAE', 'y')]
546 l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU', 'y'),
547 iommu_support_is_set)]
549 # 'self_protection', 'clipos'
550 l += [KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set')]
553 if arch in ('X86_64', 'ARM64', 'X86_32'):
554 l += [KconfigCheck('security_policy', 'defconfig', 'SECURITY', 'y')] # and choose your favourite LSM
556 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY', 'y')] # and choose your favourite LSM
557 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_YAMA', 'y')]
558 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LANDLOCK', 'y')]
559 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_DISABLE', 'is not set')]
560 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_BOOTPARAM', 'is not set')]
561 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_DEVELOP', 'is not set')]
562 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LOCKDOWN_LSM', 'y')]
563 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LOCKDOWN_LSM_EARLY', 'y')]
564 l += [KconfigCheck('security_policy', 'kspp', 'LOCK_DOWN_KERNEL_FORCE_CONFIDENTIALITY', 'y')]
565 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_WRITABLE_HOOKS', 'is not set')] # refers to SECURITY_SELINUX_DISABLE
567 # 'cut_attack_surface', 'defconfig'
568 l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'BPF_UNPRIV_DEFAULT_OFF', 'y'),
569 bpf_syscall_not_set)] # see unprivileged_bpf_disabled
570 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP', 'y')]
571 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP_FILTER', 'y')]
572 if arch in ('X86_64', 'ARM64', 'X86_32'):
573 l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'STRICT_DEVMEM', 'y'),
574 devmem_not_set)] # refers to LOCKDOWN
576 # 'cut_attack_surface', 'kspp'
577 l += [KconfigCheck('cut_attack_surface', 'kspp', 'SECURITY_DMESG_RESTRICT', 'y')]
578 l += [KconfigCheck('cut_attack_surface', 'kspp', 'ACPI_CUSTOM_METHOD', 'is not set')] # refers to LOCKDOWN
579 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_BRK', 'is not set')]
580 l += [KconfigCheck('cut_attack_surface', 'kspp', 'DEVKMEM', 'is not set')] # refers to LOCKDOWN
581 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_VDSO', 'is not set')]
582 l += [KconfigCheck('cut_attack_surface', 'kspp', 'BINFMT_MISC', 'is not set')]
583 l += [KconfigCheck('cut_attack_surface', 'kspp', 'INET_DIAG', 'is not set')]
584 l += [KconfigCheck('cut_attack_surface', 'kspp', 'KEXEC', 'is not set')] # refers to LOCKDOWN
585 l += [KconfigCheck('cut_attack_surface', 'kspp', 'PROC_KCORE', 'is not set')] # refers to LOCKDOWN
586 l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_PTYS', 'is not set')]
587 l += [KconfigCheck('cut_attack_surface', 'kspp', 'HIBERNATION', 'is not set')] # refers to LOCKDOWN
588 l += [KconfigCheck('cut_attack_surface', 'kspp', 'IA32_EMULATION', 'is not set')]
589 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_X32', 'is not set')]
590 l += [KconfigCheck('cut_attack_surface', 'kspp', 'MODIFY_LDT_SYSCALL', 'is not set')]
591 l += [KconfigCheck('cut_attack_surface', 'kspp', 'OABI_COMPAT', 'is not set')]
592 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_MSR', 'is not set')] # refers to LOCKDOWN
593 l += [modules_not_set]
594 l += [devmem_not_set]
595 l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'IO_STRICT_DEVMEM', 'y'),
596 devmem_not_set)] # refers to LOCKDOWN
597 l += [AND(KconfigCheck('cut_attack_surface', 'kspp', 'LDISC_AUTOLOAD', 'is not set'),
598 KconfigCheck('cut_attack_surface', 'kspp', 'LDISC_AUTOLOAD', 'is present'))]
600 l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'STRICT_DEVMEM', 'y'),
601 devmem_not_set)] # refers to LOCKDOWN
603 l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y')] # 'vsyscall=none'
605 # 'cut_attack_surface', 'grsec'
606 l += [KconfigCheck('cut_attack_surface', 'grsec', 'ZSMALLOC_STAT', 'is not set')]
607 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PAGE_OWNER', 'is not set')]
608 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_KMEMLEAK', 'is not set')]
609 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BINFMT_AOUT', 'is not set')]
610 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KPROBE_EVENTS', 'is not set')]
611 l += [KconfigCheck('cut_attack_surface', 'grsec', 'UPROBE_EVENTS', 'is not set')]
612 l += [KconfigCheck('cut_attack_surface', 'grsec', 'GENERIC_TRACER', 'is not set')] # refers to LOCKDOWN
613 l += [KconfigCheck('cut_attack_surface', 'grsec', 'FUNCTION_TRACER', 'is not set')]
614 l += [KconfigCheck('cut_attack_surface', 'grsec', 'STACK_TRACER', 'is not set')]
615 l += [KconfigCheck('cut_attack_surface', 'grsec', 'HIST_TRIGGERS', 'is not set')]
616 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BLK_DEV_IO_TRACE', 'is not set')]
617 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_VMCORE', 'is not set')]
618 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_PAGE_MONITOR', 'is not set')]
619 l += [KconfigCheck('cut_attack_surface', 'grsec', 'USELIB', 'is not set')]
620 l += [KconfigCheck('cut_attack_surface', 'grsec', 'CHECKPOINT_RESTORE', 'is not set')]
621 l += [KconfigCheck('cut_attack_surface', 'grsec', 'USERFAULTFD', 'is not set')]
622 l += [KconfigCheck('cut_attack_surface', 'grsec', 'HWPOISON_INJECT', 'is not set')]
623 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MEM_SOFT_DIRTY', 'is not set')]
624 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEVPORT', 'is not set')] # refers to LOCKDOWN
625 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set')] # refers to LOCKDOWN
626 l += [KconfigCheck('cut_attack_surface', 'grsec', 'NOTIFIER_ERROR_INJECTION', 'is not set')]
627 l += [KconfigCheck('cut_attack_surface', 'grsec', 'FAIL_FUTEX', 'is not set')]
628 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PUNIT_ATOM_DEBUG', 'is not set')]
629 l += [KconfigCheck('cut_attack_surface', 'grsec', 'ACPI_CONFIGFS', 'is not set')]
630 l += [KconfigCheck('cut_attack_surface', 'grsec', 'EDAC_DEBUG', 'is not set')]
631 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DRM_I915_DEBUG', 'is not set')]
632 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BCACHE_CLOSURES_DEBUG', 'is not set')]
633 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DVB_C8SECTPFE', 'is not set')]
634 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_SLRAM', 'is not set')]
635 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_PHRAM', 'is not set')]
636 l += [KconfigCheck('cut_attack_surface', 'grsec', 'IO_URING', 'is not set')]
637 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCMP', 'is not set')]
638 l += [KconfigCheck('cut_attack_surface', 'grsec', 'RSEQ', 'is not set')]
639 l += [KconfigCheck('cut_attack_surface', 'grsec', 'LATENCYTOP', 'is not set')]
640 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCOV', 'is not set')]
641 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROVIDE_OHCI1394_DMA_INIT', 'is not set')]
642 l += [KconfigCheck('cut_attack_surface', 'grsec', 'SUNRPC_DEBUG', 'is not set')]
643 l += [AND(KconfigCheck('cut_attack_surface', 'grsec', 'PTDUMP_DEBUGFS', 'is not set'),
644 KconfigCheck('cut_attack_surface', 'grsec', 'X86_PTDUMP', 'is not set'))]
646 # 'cut_attack_surface', 'maintainer'
647 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'DRM_LEGACY', 'is not set')] # recommended by Daniel Vetter in /issues/38
648 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'FB', 'is not set')] # recommended by Daniel Vetter in /issues/38
649 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'VT', 'is not set')] # recommended by Daniel Vetter in /issues/38
650 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD', 'is not set')] # recommended by Denis Efremov in /pull/54
651 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD_RAWCMD', 'is not set')] # recommended by Denis Efremov in /pull/62
653 # 'cut_attack_surface', 'grapheneos'
654 l += [KconfigCheck('cut_attack_surface', 'grapheneos', 'AIO', 'is not set')]
656 # 'cut_attack_surface', 'clipos'
657 l += [KconfigCheck('cut_attack_surface', 'clipos', 'STAGING', 'is not set')]
658 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KSM', 'is not set')] # to prevent FLUSH+RELOAD attack
659 # l += [KconfigCheck('cut_attack_surface', 'clipos', 'IKCONFIG', 'is not set')] # no, IKCONFIG is needed for this check :)
660 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KALLSYMS', 'is not set')]
661 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_VSYSCALL_EMULATION', 'is not set')]
662 l += [KconfigCheck('cut_attack_surface', 'clipos', 'MAGIC_SYSRQ', 'is not set')]
663 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KEXEC_FILE', 'is not set')] # refers to LOCKDOWN (permissive)
664 l += [KconfigCheck('cut_attack_surface', 'clipos', 'USER_NS', 'is not set')] # user.max_user_namespaces=0
665 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_CPUID', 'is not set')]
666 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_IOPL_IOPERM', 'is not set')] # refers to LOCKDOWN
667 l += [KconfigCheck('cut_attack_surface', 'clipos', 'ACPI_TABLE_UPGRADE', 'is not set')] # refers to LOCKDOWN
668 l += [KconfigCheck('cut_attack_surface', 'clipos', 'EFI_CUSTOM_SSDT_OVERLAYS', 'is not set')]
669 l += [KconfigCheck('cut_attack_surface', 'clipos', 'COREDUMP', 'is not set')] # cut userspace attack surface
670 if arch in ('X86_64', 'X86_32'):
671 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_INTEL_TSX_MODE_OFF', 'y')] # tsx=off
673 # 'cut_attack_surface', 'lockdown'
674 l += [bpf_syscall_not_set] # refers to LOCKDOWN
675 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'EFI_TEST', 'is not set')] # refers to LOCKDOWN
676 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'MMIOTRACE_TEST', 'is not set')] # refers to LOCKDOWN
677 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'KPROBES', 'is not set')] # refers to LOCKDOWN
679 # 'cut_attack_surface', 'my'
680 l += [OR(KconfigCheck('cut_attack_surface', 'my', 'TRIM_UNUSED_KSYMS', 'y'),
682 l += [KconfigCheck('cut_attack_surface', 'my', 'MMIOTRACE', 'is not set')] # refers to LOCKDOWN (permissive)
683 l += [KconfigCheck('cut_attack_surface', 'my', 'LIVEPATCH', 'is not set')]
684 l += [KconfigCheck('cut_attack_surface', 'my', 'IP_DCCP', 'is not set')]
685 l += [KconfigCheck('cut_attack_surface', 'my', 'IP_SCTP', 'is not set')]
686 l += [KconfigCheck('cut_attack_surface', 'my', 'FTRACE', 'is not set')] # refers to LOCKDOWN
687 l += [KconfigCheck('cut_attack_surface', 'my', 'VIDEO_VIVID', 'is not set')]
688 l += [KconfigCheck('cut_attack_surface', 'my', 'INPUT_EVBUG', 'is not set')] # Can be used as a keylogger
689 l += [KconfigCheck('cut_attack_surface', 'my', 'KGDB', 'is not set')]
692 if arch in ('X86_64', 'ARM64', 'X86_32'):
693 l += [KconfigCheck('harden_userspace', 'defconfig', 'INTEGRITY', 'y')]
695 l += [KconfigCheck('harden_userspace', 'my', 'INTEGRITY', 'y')]
697 l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_PTR_AUTH', 'y')]
698 l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_BTI', 'y')]
699 if arch in ('ARM', 'X86_32'):
700 l += [KconfigCheck('harden_userspace', 'defconfig', 'VMSPLIT_3G', 'y')]
701 if arch in ('X86_64', 'ARM64'):
702 l += [KconfigCheck('harden_userspace', 'clipos', 'ARCH_MMAP_RND_BITS', '32')]
703 if arch in ('X86_32', 'ARM'):
704 l += [KconfigCheck('harden_userspace', 'my', 'ARCH_MMAP_RND_BITS', '16')]
707 def add_cmdline_checks(l, arch):
708 # Calling the CmdlineCheck class constructor:
709 # CmdlineCheck(reason, decision, name, expected)
711 # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
712 # when the tool doesn't check the cmdline.
714 # [!] Make sure that values of the options in CmdlineChecks need normalization.
715 # For more info see normalize_cmdline_options().
717 # A common pattern for checking the 'param_x' cmdline parameter
718 # that __overrides__ the 'PARAM_X_DEFAULT' kconfig option:
719 # l += [OR(CmdlineCheck(reason, decision, 'param_x', '1'),
720 # AND(KconfigCheck(reason, decision, 'PARAM_X_DEFAULT_ON', 'y'),
721 # CmdlineCheck(reason, decision, 'param_x, 'is not set')))]
723 # Here we don't check the kconfig options or minimal kernel version
724 # required for the cmdline parameters. That would make the checks
725 # very complex and not give a 100% guarantee anyway.
727 # 'self_protection', 'defconfig'
728 l += [CmdlineCheck('self_protection', 'defconfig', 'nosmep', 'is not set')]
729 l += [CmdlineCheck('self_protection', 'defconfig', 'nosmap', 'is not set')]
730 l += [CmdlineCheck('self_protection', 'defconfig', 'nokaslr', 'is not set')]
731 l += [CmdlineCheck('self_protection', 'defconfig', 'nopti', 'is not set')]
732 l += [CmdlineCheck('self_protection', 'defconfig', 'nospectre_v1', 'is not set')]
733 l += [CmdlineCheck('self_protection', 'defconfig', 'nospectre_v2', 'is not set')]
734 l += [CmdlineCheck('self_protection', 'defconfig', 'nospec_store_bypass_disable', 'is not set')]
735 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'mitigations', 'is not off'),
736 CmdlineCheck('self_protection', 'defconfig', 'mitigations', 'is not set'))]
737 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'spectre_v2', 'is not off'),
738 CmdlineCheck('self_protection', 'defconfig', 'spectre_v2', 'is not set'))]
739 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'spec_store_bypass_disable', 'is not off'),
740 CmdlineCheck('self_protection', 'defconfig', 'spec_store_bypass_disable', 'is not set'))]
742 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', 'full'),
743 AND(KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y'),
744 CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set')))]
746 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', '1'),
747 CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set'))]
749 # 'self_protection', 'kspp'
750 l += [CmdlineCheck('self_protection', 'kspp', 'nosmt', 'is present')]
751 l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', '1'),
752 AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y'),
753 CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', 'is not set')))]
754 l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_free', '1'),
755 AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
756 CmdlineCheck('self_protection', 'kspp', 'init_on_free', 'is not set')),
757 AND(CmdlineCheck('self_protection', 'kspp', 'page_poison', '1'),
758 KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'),
759 CmdlineCheck('self_protection', 'kspp', 'slub_debug', 'P')))]
760 l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_nomerge', 'is present'),
761 AND(KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set'),
762 CmdlineCheck('self_protection', 'kspp', 'slab_merge', 'is not set')))]
763 l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.strict', '1'),
764 AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y'),
765 CmdlineCheck('self_protection', 'kspp', 'iommu.strict', 'is not set')))]
766 l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', '0'),
767 AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set'),
768 CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', 'is not set')))]
769 # The cmdline checks compatible with the kconfig recommendations of the KSPP project...
770 l += [OR(CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', '1'),
771 AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y'),
772 CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', 'is not set')))]
773 l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', '0'),
774 AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
775 CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', 'is not set')))]
777 if arch in ('X86_64', 'ARM64', 'X86_32'):
778 l += [OR(CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', '1'),
779 AND(KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y'),
780 CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', 'is not set')))]
781 if arch in ('X86_64', 'X86_32'):
782 l += [AND(CmdlineCheck('self_protection', 'kspp', 'pti', 'on'),
783 CmdlineCheck('self_protection', 'defconfig', 'nopti', 'is not set'))]
785 # 'self_protection', 'clipos'
786 l += [CmdlineCheck('self_protection', 'clipos', 'page_alloc.shuffle', '1')]
788 # 'cut_attack_surface', 'kspp'
790 l += [OR(CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'none'),
791 AND(KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y'),
792 CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'is not set')))]
794 # 'cut_attack_surface', 'grsec'
795 # The cmdline checks compatible with the kconfig options disabled by grsecurity...
796 l += [OR(CmdlineCheck('cut_attack_surface', 'grsec', 'debugfs', 'off'),
797 KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set'))] # ... the end
800 def print_unknown_options(checklist, parsed_options):
804 if o1.type != 'complex':
805 known_options.append(o1.name)
808 if o2.type != 'complex':
809 if hasattr(o2, 'name'):
810 known_options.append(o2.name)
813 assert(o3.type != 'complex'), \
814 'unexpected ComplexOptCheck inside {}'.format(o2.name)
815 if hasattr(o3, 'name'):
816 known_options.append(o3.name)
818 for option, value in parsed_options.items():
819 if option not in known_options:
820 print('[?] No check for option {} ({})'.format(option, value))
823 def print_checklist(mode, checklist, with_results):
827 output.append(o.json_dump(with_results))
828 print(json.dumps(output))
835 print('=' * sep_line_len)
836 print('{:^40}|{:^7}|{:^12}|{:^10}|{:^18}'.format('option name', 'type', 'desired val', 'decision', 'reason'), end='')
838 print('| {}'.format('check result'), end='')
840 print('=' * sep_line_len)
843 for opt in checklist:
845 if mode == 'show_ok':
846 if not opt.result.startswith('OK'):
848 if mode == 'show_fail':
849 if not opt.result.startswith('FAIL'):
851 opt.table_print(mode, with_results)
853 if mode == 'verbose':
854 print('-' * sep_line_len)
859 fail_count = len(list(filter(lambda opt: opt.result.startswith('FAIL'), checklist)))
861 ok_count = len(list(filter(lambda opt: opt.result.startswith('OK'), checklist)))
863 if mode == 'show_ok':
864 fail_suppressed = ' (suppressed in output)'
865 if mode == 'show_fail':
866 ok_suppressed = ' (suppressed in output)'
868 print('[+] Config check is finished: \'OK\' - {}{} / \'FAIL\' - {}{}'.format(ok_count, ok_suppressed, fail_count, fail_suppressed))
871 def populate_simple_opt_with_data(opt, data, data_type):
872 assert(opt.type != 'complex'), \
873 'unexpected ComplexOptCheck "{}"'.format(opt.name)
874 assert(opt.type in SIMPLE_OPTION_TYPES), \
875 'invalid opt type "{}"'.format(opt.type)
876 assert(data_type in SIMPLE_OPTION_TYPES), \
877 'invalid data type "{}"'.format(data_type)
879 if data_type != opt.type:
882 if data_type in ('kconfig', 'cmdline'):
883 opt.state = data.get(opt.name, None)
885 assert(data_type == 'version'), \
886 'unexpected data type "{}"'.format(data_type)
890 def populate_opt_with_data(opt, data, data_type):
891 if opt.type == 'complex':
893 if o.type == 'complex':
894 # Recursion for nested ComplexOptCheck objects
895 populate_opt_with_data(o, data, data_type)
897 populate_simple_opt_with_data(o, data, data_type)
899 assert(opt.type in ('kconfig', 'cmdline')), \
900 'bad type "{}" for a simple check'.format(opt.type)
901 populate_simple_opt_with_data(opt, data, data_type)
904 def populate_with_data(checklist, data, data_type):
905 for opt in checklist:
906 populate_opt_with_data(opt, data, data_type)
909 def perform_checks(checklist):
910 for opt in checklist:
914 def parse_kconfig_file(parsed_options, fname):
915 with open(fname, 'r') as f:
916 opt_is_on = re.compile("CONFIG_[a-zA-Z0-9_]*=[a-zA-Z0-9_\"]*")
917 opt_is_off = re.compile("# CONFIG_[a-zA-Z0-9_]* is not set")
919 for line in f.readlines():
924 if opt_is_on.match(line):
925 option, value = line.split('=', 1)
926 if value == 'is not set':
927 sys.exit('[!] ERROR: bad enabled kconfig option "{}"'.format(line))
928 elif opt_is_off.match(line):
929 option, value = line[2:].split(' ', 1)
930 if value != 'is not set':
931 sys.exit('[!] ERROR: bad disabled kconfig option "{}"'.format(line))
933 if option in parsed_options:
934 sys.exit('[!] ERROR: kconfig option "{}" exists multiple times'.format(line))
937 parsed_options[option] = value
940 def normalize_cmdline_options(option, value):
941 # Don't normalize the cmdline option values if
942 # the Linux kernel doesn't use kstrtobool() for them
943 if option == 'debugfs':
944 # See debugfs_kernel() in fs/debugfs/inode.c
946 if option == 'mitigations':
947 # See mitigations_parse_cmdline() in kernel/cpu.c
950 # See pti_check_boottime_disable() in arch/x86/mm/pti.c
952 if option == 'spectre_v2':
953 # See spectre_v2_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
955 if option == 'spec_store_bypass_disable':
956 # See ssb_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
959 # Implement a limited part of the kstrtobool() logic
960 if value in ('1', 'on', 'On', 'ON', 'y', 'Y', 'yes', 'Yes', 'YES'):
962 if value in ('0', 'off', 'Off', 'OFF', 'n', 'N', 'no', 'No', 'NO'):
965 # Preserve unique values
969 def parse_cmdline_file(parsed_options, fname):
970 with open(fname, 'r') as f:
976 sys.exit('[!] ERROR: more than one line in "{}"'.format(fname))
980 name, value = opt.split('=', 1)
983 value = '' # '' is not None
984 value = normalize_cmdline_options(name, value)
985 parsed_options[name] = value
991 # - reporting about unknown kernel options in the kconfig
992 # - verbose printing of ComplexOptCheck items
993 # * json mode for printing the results in JSON format
994 report_modes = ['verbose', 'json', 'show_ok', 'show_fail']
995 supported_archs = ['X86_64', 'X86_32', 'ARM64', 'ARM']
996 parser = ArgumentParser(prog='kconfig-hardened-check',
997 description='A tool for checking the security hardening options of the Linux kernel')
998 parser.add_argument('--version', action='version', version='%(prog)s ' + __version__)
999 parser.add_argument('-p', '--print', choices=supported_archs,
1000 help='print security hardening preferences for the selected architecture')
1001 parser.add_argument('-c', '--config',
1002 help='check the kernel kconfig file against these preferences')
1003 parser.add_argument('-l', '--cmdline',
1004 help='check the kernel cmdline file against these preferences')
1005 parser.add_argument('-m', '--mode', choices=report_modes,
1006 help='choose the report mode')
1007 args = parser.parse_args()
1013 print('[+] Special report mode: {}'.format(mode))
1015 config_checklist = []
1019 sys.exit('[!] ERROR: --config and --print can\'t be used together')
1022 print('[+] Kconfig file to check: {}'.format(args.config))
1024 print('[+] Kernel cmdline file to check: {}'.format(args.cmdline))
1026 arch, msg = detect_arch(args.config, supported_archs)
1028 sys.exit('[!] ERROR: {}'.format(msg))
1030 print('[+] Detected architecture: {}'.format(arch))
1032 kernel_version, msg = detect_kernel_version(args.config)
1033 if not kernel_version:
1034 sys.exit('[!] ERROR: {}'.format(msg))
1036 print('[+] Detected kernel version: {}.{}'.format(kernel_version[0], kernel_version[1]))
1038 compiler, msg = detect_compiler(args.config)
1041 print('[+] Detected compiler: {}'.format(compiler))
1043 print('[-] Can\'t detect the compiler: {}'.format(msg))
1045 # add relevant kconfig checks to the checklist
1046 add_kconfig_checks(config_checklist, arch)
1049 # add relevant cmdline checks to the checklist
1050 add_cmdline_checks(config_checklist, arch)
1052 # populate the checklist with the parsed kconfig data
1053 parsed_kconfig_options = OrderedDict()
1054 parse_kconfig_file(parsed_kconfig_options, args.config)
1055 populate_with_data(config_checklist, parsed_kconfig_options, 'kconfig')
1056 populate_with_data(config_checklist, kernel_version, 'version')
1059 # populate the checklist with the parsed kconfig data
1060 parsed_cmdline_options = OrderedDict()
1061 parse_cmdline_file(parsed_cmdline_options, args.cmdline)
1062 populate_with_data(config_checklist, parsed_cmdline_options, 'cmdline')
1064 # now everything is ready for performing the checks
1065 perform_checks(config_checklist)
1067 # finally print the results
1068 if mode == 'verbose':
1069 print_unknown_options(config_checklist, parsed_kconfig_options)
1070 print_checklist(mode, config_checklist, True)
1074 sys.exit('[!] ERROR: checking cmdline doesn\'t work without checking kconfig')
1077 if mode in ('show_ok', 'show_fail'):
1078 sys.exit('[!] ERROR: wrong mode "{}" for --print'.format(mode))
1080 add_kconfig_checks(config_checklist, arch)
1081 add_cmdline_checks(config_checklist, arch)
1083 print('[+] Printing kernel security hardening preferences for {}...'.format(arch))
1084 print_checklist(mode, config_checklist, False)