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)
26 # sysrq_always_enabled
31 # Hardware tag-based KASAN with arm64 Memory Tagging Extension (MTE):
33 # kasan.stacktrace=off
36 # N.B. Hardening sysctls:
37 # kernel.kptr_restrict=2 (or 1?)
38 # kernel.dmesg_restrict=1 (also see the kconfig option)
39 # kernel.perf_event_paranoid=3
40 # kernel.kexec_load_disabled=1
41 # kernel.yama.ptrace_scope=3
42 # user.max_user_namespaces=0
43 # what about bpf_jit_enable?
44 # kernel.unprivileged_bpf_disabled=1
45 # net.core.bpf_jit_harden=2
46 # vm.unprivileged_userfaultfd=0
47 # (at first, it disabled unprivileged userfaultfd,
48 # and since v5.11 it enables unprivileged userfaultfd for user-mode only)
49 # vm.mmap_min_addr has a good value
50 # dev.tty.ldisc_autoload=0
51 # fs.protected_symlinks=1
52 # fs.protected_hardlinks=1
53 # fs.protected_fifos=2
54 # fs.protected_regular=2
56 # kernel.modules_disabled=1
57 # kernel.randomize_va_space = 2
60 # pylint: disable=missing-module-docstring,missing-class-docstring,missing-function-docstring
61 # pylint: disable=line-too-long,invalid-name,too-many-branches,too-many-statements
65 from argparse import ArgumentParser
66 from collections import OrderedDict
69 from .__about__ import __version__
71 SIMPLE_OPTION_TYPES = ('kconfig', 'version', 'cmdline')
74 def __init__(self, reason, decision, name, expected):
75 assert(name and name == name.strip() and len(name.split()) == 1), \
76 'invalid name "{}" for {}'.format(name, self.__class__.__name__)
79 assert(decision and decision == decision.strip() and len(decision.split()) == 1), \
80 'invalid decision "{}" for "{}" check'.format(decision, name)
81 self.decision = decision
83 assert(reason and reason == reason.strip() and len(reason.split()) == 1), \
84 'invalid reason "{}" for "{}" check'.format(reason, name)
87 assert(expected and expected == expected.strip()), \
88 'invalid expected value "{}" for "{}" check (1)'.format(expected, name)
89 val_len = len(expected.split())
91 assert(expected == 'is not set' or expected == 'is not off'), \
92 'invalid expected value "{}" for "{}" check (2)'.format(expected, name)
94 assert(expected == 'is present'), \
95 'invalid expected value "{}" for "{}" check (3)'.format(expected, name)
97 assert(val_len == 1), \
98 'invalid expected value "{}" for "{}" check (4)'.format(expected, name)
99 self.expected = expected
109 # handle the 'is present' check
110 if self.expected == 'is present':
111 if self.state is None:
112 self.result = 'FAIL: is not present'
114 self.result = 'OK: is present'
117 # handle the 'is not off' option check
118 if self.expected == 'is not off':
119 if self.state == 'off':
120 self.result = 'FAIL: is off'
121 elif self.state is None:
122 self.result = 'FAIL: is off, not found'
124 self.result = 'OK: is not off, "' + self.state + '"'
127 # handle the option value check
128 if self.expected == self.state:
130 elif self.state is None:
131 if self.expected == 'is not set':
132 self.result = 'OK: is not found'
134 self.result = 'FAIL: is not found'
136 self.result = 'FAIL: "' + self.state + '"'
138 def table_print(self, _mode, with_results):
139 print('{:<40}|{:^7}|{:^12}|{:^10}|{:^18}'.format(self.name, self.type, self.expected, self.decision, self.reason), end='')
141 print('| {}'.format(self.result), end='')
143 def json_dump(self, with_results):
144 dump = [self.name, self.type, self.expected, self.decision, self.reason]
146 dump.append(self.result)
150 class KconfigCheck(OptCheck):
151 def __init__(self, *args, **kwargs):
152 super().__init__(*args, **kwargs)
153 self.name = 'CONFIG_' + self.name
160 class CmdlineCheck(OptCheck):
167 def __init__(self, ver_expected):
168 assert(ver_expected and isinstance(ver_expected, tuple) and len(ver_expected) == 2), \
169 'invalid version "{}" for VersionCheck'.format(ver_expected)
170 self.ver_expected = ver_expected
179 if self.ver[0] > self.ver_expected[0]:
180 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
182 if self.ver[0] < self.ver_expected[0]:
183 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
185 if self.ver[1] >= self.ver_expected[1]:
186 self.result = 'OK: version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
188 self.result = 'FAIL: version < ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
190 def table_print(self, _mode, with_results):
191 ver_req = 'kernel version >= ' + str(self.ver_expected[0]) + '.' + str(self.ver_expected[1])
192 print('{:<91}'.format(ver_req), end='')
194 print('| {}'.format(self.result), end='')
197 class ComplexOptCheck:
198 def __init__(self, *opts):
201 'empty {} check'.format(self.__class__.__name__)
202 assert(len(self.opts) != 1), \
203 'useless {} check: {}'.format(self.__class__.__name__, opts)
204 assert(isinstance(opts[0], (KconfigCheck, CmdlineCheck))), \
205 'invalid {} check: {}'.format(self.__class__.__name__, opts)
214 return self.opts[0].name
218 return self.opts[0].expected
220 def table_print(self, mode, with_results):
221 if mode == 'verbose':
222 print(' {:87}'.format('<<< ' + self.__class__.__name__ + ' >>>'), end='')
224 print('| {}'.format(self.result), end='')
227 o.table_print(mode, with_results)
230 o.table_print(mode, False)
232 print('| {}'.format(self.result), end='')
234 def json_dump(self, with_results):
235 dump = self.opts[0].json_dump(False)
237 dump.append(self.result)
241 class OR(ComplexOptCheck):
242 # self.opts[0] is the option that this OR-check is about.
244 # OR(<X_is_hardened>, <X_is_disabled>)
245 # OR(<X_is_hardened>, <old_X_is_hardened>)
247 for i, opt in enumerate(self.opts):
249 if opt.result.startswith('OK'):
250 self.result = opt.result
251 # Add more info for additional checks:
253 if opt.result == 'OK':
254 self.result = 'OK: {} is "{}"'.format(opt.name, opt.expected)
255 elif opt.result == 'OK: is not found':
256 self.result = 'OK: {} is not found'.format(opt.name)
257 elif opt.result == 'OK: is present':
258 self.result = 'OK: {} is present'.format(opt.name)
259 elif opt.result.startswith('OK: is not off'):
260 self.result = 'OK: {} is not off'.format(opt.name)
262 # VersionCheck provides enough info
263 assert(opt.result.startswith('OK: version')), \
264 'unexpected OK description "{}"'.format(opt.result)
266 self.result = self.opts[0].result
269 class AND(ComplexOptCheck):
270 # self.opts[0] is the option that this AND-check is about.
272 # AND(<suboption>, <main_option>)
273 # Suboption is not checked if checking of the main_option is failed.
274 # AND(<X_is_disabled>, <old_X_is_disabled>)
276 for i, opt in reversed(list(enumerate(self.opts))):
279 self.result = opt.result
281 if not opt.result.startswith('OK'):
282 # This FAIL is caused by additional checks,
283 # and not by the main option that this AND-check is about.
284 # Describe the reason of the FAIL.
285 if opt.result.startswith('FAIL: \"') or opt.result == 'FAIL: is not found':
286 self.result = 'FAIL: {} is not "{}"'.format(opt.name, opt.expected)
287 elif opt.result == 'FAIL: is not present':
288 self.result = 'FAIL: {} is not present'.format(opt.name)
289 elif opt.result == 'FAIL: is off':
290 self.result = 'FAIL: {} is off'.format(opt.name)
291 elif opt.result == 'FAIL: is off, not found':
292 self.result = 'FAIL: {} is off, not found'.format(opt.name)
294 # VersionCheck provides enough info
295 self.result = opt.result
296 assert(opt.result.startswith('FAIL: version')), \
297 'unexpected FAIL description "{}"'.format(opt.result)
301 def detect_arch(fname, archs):
302 with open(fname, 'r') as f:
303 arch_pattern = re.compile("CONFIG_[a-zA-Z0-9_]*=y")
305 for line in f.readlines():
306 if arch_pattern.match(line):
307 option, _ = line[7:].split('=', 1)
312 return None, 'more than one supported architecture is detected'
314 return None, 'failed to detect architecture'
318 def detect_kernel_version(fname):
319 with open(fname, 'r') as f:
320 ver_pattern = re.compile("# Linux/.* Kernel Configuration")
321 for line in f.readlines():
322 if ver_pattern.match(line):
326 ver_numbers = ver_str.split('.')
327 if len(ver_numbers) < 3 or not ver_numbers[0].isdigit() or not ver_numbers[1].isdigit():
328 msg = 'failed to parse the version "' + ver_str + '"'
330 return (int(ver_numbers[0]), int(ver_numbers[1])), None
331 return None, 'no kernel version detected'
334 def detect_compiler(fname):
337 with open(fname, 'r') as f:
338 gcc_version_pattern = re.compile("CONFIG_GCC_VERSION=[0-9]*")
339 clang_version_pattern = re.compile("CONFIG_CLANG_VERSION=[0-9]*")
340 for line in f.readlines():
341 if gcc_version_pattern.match(line):
342 gcc_version = line[19:-1]
343 if clang_version_pattern.match(line):
344 clang_version = line[21:-1]
345 if not gcc_version or not clang_version:
346 return None, 'no CONFIG_GCC_VERSION or CONFIG_CLANG_VERSION'
347 if gcc_version == '0' and clang_version != '0':
348 return 'CLANG ' + clang_version, 'OK'
349 if gcc_version != '0' and clang_version == '0':
350 return 'GCC ' + gcc_version, 'OK'
351 sys.exit('[!] ERROR: invalid GCC_VERSION and CLANG_VERSION: {} {}'.format(gcc_version, clang_version))
354 def add_kconfig_checks(l, arch):
355 # Calling the KconfigCheck class constructor:
356 # KconfigCheck(reason, decision, name, expected)
358 # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
359 # when the tool doesn't check the cmdline.
361 efi_not_set = KconfigCheck('-', '-', 'EFI', 'is not set')
362 cc_is_gcc = KconfigCheck('-', '-', 'CC_IS_GCC', 'y') # exists since v4.18
363 cc_is_clang = KconfigCheck('-', '-', 'CC_IS_CLANG', 'y') # exists since v4.18
365 modules_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'MODULES', 'is not set')
366 devmem_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'DEVMEM', 'is not set') # refers to LOCKDOWN
367 bpf_syscall_not_set = KconfigCheck('cut_attack_surface', 'lockdown', 'BPF_SYSCALL', 'is not set') # refers to LOCKDOWN
369 # 'self_protection', 'defconfig'
370 l += [KconfigCheck('self_protection', 'defconfig', 'BUG', 'y')]
371 l += [KconfigCheck('self_protection', 'defconfig', 'SLUB_DEBUG', 'y')]
372 l += [KconfigCheck('self_protection', 'defconfig', 'THREAD_INFO_IN_TASK', 'y')]
373 gcc_plugins_support_is_set = KconfigCheck('self_protection', 'defconfig', 'GCC_PLUGINS', 'y')
374 l += [gcc_plugins_support_is_set]
375 iommu_support_is_set = KconfigCheck('self_protection', 'defconfig', 'IOMMU_SUPPORT', 'y')
376 l += [iommu_support_is_set] # is needed for mitigating DMA attacks
377 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR', 'y'),
378 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR', 'y'),
379 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_REGULAR', 'y'),
380 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_AUTO', 'y'),
381 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
382 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_STRONG', 'y'),
383 KconfigCheck('self_protection', 'defconfig', 'CC_STACKPROTECTOR_STRONG', 'y'))]
384 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_KERNEL_RWX', 'y'),
385 KconfigCheck('self_protection', 'defconfig', 'DEBUG_RODATA', 'y'))] # before v4.11
386 l += [OR(KconfigCheck('self_protection', 'defconfig', 'STRICT_MODULE_RWX', 'y'),
387 KconfigCheck('self_protection', 'defconfig', 'DEBUG_SET_MODULE_RONX', 'y'),
388 modules_not_set)] # DEBUG_SET_MODULE_RONX was before v4.11
389 l += [OR(KconfigCheck('self_protection', 'defconfig', 'REFCOUNT_FULL', 'y'),
390 VersionCheck((5, 5)))] # REFCOUNT_FULL is enabled by default since v5.5
391 if arch in ('X86_64', 'ARM64', 'X86_32'):
392 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y')]
393 if arch in ('X86_64', 'ARM64'):
394 l += [KconfigCheck('self_protection', 'defconfig', 'VMAP_STACK', 'y')]
395 if arch in ('X86_64', 'X86_32'):
396 l += [KconfigCheck('self_protection', 'defconfig', 'X86_MCE', 'y')]
397 l += [KconfigCheck('self_protection', 'defconfig', 'X86_MCE_INTEL', 'y')]
398 l += [KconfigCheck('self_protection', 'defconfig', 'X86_MCE_AMD', 'y')]
399 l += [KconfigCheck('self_protection', 'defconfig', 'MICROCODE', 'y')] # is needed for mitigating CPU bugs
400 l += [KconfigCheck('self_protection', 'defconfig', 'RETPOLINE', 'y')]
401 l += [KconfigCheck('self_protection', 'defconfig', 'SYN_COOKIES', 'y')] # another reason?
402 l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_SMAP', 'y'),
403 VersionCheck((5, 19)))] # X86_SMAP is enabled by default since v5.19
404 l += [OR(KconfigCheck('self_protection', 'defconfig', 'X86_UMIP', 'y'),
405 KconfigCheck('self_protection', 'defconfig', 'X86_INTEL_UMIP', 'y'))]
406 if arch in ('ARM64', 'ARM'):
407 l += [KconfigCheck('self_protection', 'defconfig', 'STACKPROTECTOR_PER_TASK', 'y')]
409 l += [KconfigCheck('self_protection', 'defconfig', 'PAGE_TABLE_ISOLATION', 'y')]
410 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MEMORY', 'y')]
411 l += [AND(KconfigCheck('self_protection', 'defconfig', 'INTEL_IOMMU', 'y'),
412 iommu_support_is_set)]
413 l += [AND(KconfigCheck('self_protection', 'defconfig', 'AMD_IOMMU', 'y'),
414 iommu_support_is_set)]
416 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PAN', 'y')]
417 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_EPAN', 'y')]
418 l += [KconfigCheck('self_protection', 'defconfig', 'UNMAP_KERNEL_AT_EL0', 'y')]
419 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_E0PD', 'y')]
420 l += [KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y')]
421 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_PTR_AUTH_KERNEL', 'y')]
422 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_BTI_KERNEL', 'y')]
423 l += [KconfigCheck('self_protection', 'defconfig', 'MITIGATE_SPECTRE_BRANCH_HISTORY', 'y')]
424 l += [KconfigCheck('self_protection', 'defconfig', 'ARM64_MTE', 'y')]
425 l += [KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_MODULE_REGION_FULL', 'y')]
426 l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_EL2_VECTORS', 'y'),
427 AND(KconfigCheck('self_protection', 'defconfig', 'RANDOMIZE_BASE', 'y'),
428 VersionCheck((5, 9))))] # HARDEN_EL2_VECTORS was included in RANDOMIZE_BASE in v5.9
429 l += [OR(KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y'),
430 VersionCheck((5, 10)))] # HARDEN_BRANCH_PREDICTOR is enabled by default since v5.10
432 l += [KconfigCheck('self_protection', 'defconfig', 'CPU_SW_DOMAIN_PAN', 'y')]
433 l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_PREDICTOR', 'y')]
434 l += [KconfigCheck('self_protection', 'defconfig', 'HARDEN_BRANCH_HISTORY', 'y')]
436 # 'self_protection', 'kspp'
437 l += [KconfigCheck('self_protection', 'kspp', 'BUG_ON_DATA_CORRUPTION', 'y')]
438 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_WX', 'y')]
439 l += [KconfigCheck('self_protection', 'kspp', 'SCHED_STACK_END_CHECK', 'y')]
440 l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_HARDENED', 'y')]
441 l += [KconfigCheck('self_protection', 'kspp', 'SLAB_FREELIST_RANDOM', 'y')]
442 l += [KconfigCheck('self_protection', 'kspp', 'SHUFFLE_PAGE_ALLOCATOR', 'y')]
443 l += [KconfigCheck('self_protection', 'kspp', 'FORTIFY_SOURCE', 'y')]
444 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_LIST', 'y')]
445 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_VIRTUAL', 'y')]
446 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_SG', 'y')]
447 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_CREDENTIALS', 'y')]
448 l += [KconfigCheck('self_protection', 'kspp', 'DEBUG_NOTIFIERS', 'y')]
449 l += [KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y')]
450 l += [KconfigCheck('self_protection', 'kspp', 'KFENCE', 'y')]
451 l += [KconfigCheck('self_protection', 'kspp', 'WERROR', 'y')]
452 l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y')]
453 l += [KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set')] # true if IOMMU_DEFAULT_DMA_STRICT is set
454 l += [KconfigCheck('self_protection', 'kspp', 'ZERO_CALL_USED_REGS', 'y')]
455 l += [KconfigCheck('self_protection', 'kspp', 'HW_RANDOM_TPM', 'y')]
456 l += [KconfigCheck('self_protection', 'kspp', 'STATIC_USERMODEHELPER', 'y')] # needs userspace support
457 l += [KconfigCheck('self_protection', 'kspp', 'SCHED_CORE', 'y')]
458 randstruct_is_set = OR(KconfigCheck('self_protection', 'kspp', 'RANDSTRUCT_FULL', 'y'),
459 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_RANDSTRUCT', 'y'))
460 l += [randstruct_is_set]
461 l += [AND(KconfigCheck('self_protection', 'kspp', 'RANDSTRUCT_PERFORMANCE', 'is not set'),
462 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_RANDSTRUCT_PERFORMANCE', 'is not set'),
464 hardened_usercopy_is_set = KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y')
465 l += [hardened_usercopy_is_set]
466 l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
467 hardened_usercopy_is_set)]
468 l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_PAGESPAN', 'is not set'),
469 hardened_usercopy_is_set)]
470 l += [AND(KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_LATENT_ENTROPY', 'y'),
471 gcc_plugins_support_is_set)]
472 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG', 'y'),
474 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_ALL', 'y'),
476 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_SHA512', 'y'),
478 l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG_FORCE', 'y'),
479 modules_not_set)] # refers to LOCKDOWN
480 l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_STACK_ALL_ZERO', 'y'),
481 KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STRUCTLEAK_BYREF_ALL', 'y'))]
482 l += [OR(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
483 KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'))]
484 # CONFIG_INIT_ON_FREE_DEFAULT_ON was added in v5.3.
485 # CONFIG_PAGE_POISONING_ZERO was removed in v5.11.
486 # Starting from v5.11 CONFIG_PAGE_POISONING unconditionally checks
487 # the 0xAA poison pattern on allocation.
488 # That brings higher performance penalty.
489 l += [OR(KconfigCheck('self_protection', 'kspp', 'EFI_DISABLE_PCI_DMA', 'y'),
491 l += [OR(KconfigCheck('self_protection', 'kspp', 'RESET_ATTACK_MITIGATION', 'y'),
492 efi_not_set)] # needs userspace support (systemd)
493 ubsan_bounds_is_set = KconfigCheck('self_protection', 'kspp', 'UBSAN_BOUNDS', 'y')
494 l += [ubsan_bounds_is_set]
495 l += [OR(KconfigCheck('self_protection', 'kspp', 'UBSAN_LOCAL_BOUNDS', 'y'),
496 AND(ubsan_bounds_is_set,
498 l += [AND(KconfigCheck('self_protection', 'kspp', 'UBSAN_TRAP', 'y'),
500 KconfigCheck('self_protection', 'kspp', 'UBSAN_SHIFT', 'is not set'),
501 KconfigCheck('self_protection', 'kspp', 'UBSAN_DIV_ZERO', 'is not set'),
502 KconfigCheck('self_protection', 'kspp', 'UBSAN_UNREACHABLE', 'is not set'),
503 KconfigCheck('self_protection', 'kspp', 'UBSAN_BOOL', 'is not set'),
504 KconfigCheck('self_protection', 'kspp', 'UBSAN_ENUM', 'is not set'),
505 KconfigCheck('self_protection', 'kspp', 'UBSAN_ALIGNMENT', 'is not set'))] # only array index bounds checking with traps
506 if arch in ('X86_64', 'ARM64', 'X86_32'):
507 l += [AND(KconfigCheck('self_protection', 'kspp', 'UBSAN_SANITIZE_ALL', 'y'),
508 ubsan_bounds_is_set)] # ARCH_HAS_UBSAN_SANITIZE_ALL is not enabled for ARM
509 stackleak_is_set = KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STACKLEAK', 'y')
510 l += [AND(stackleak_is_set, gcc_plugins_support_is_set)]
511 l += [AND(KconfigCheck('self_protection', 'kspp', 'STACKLEAK_METRICS', 'is not set'),
513 gcc_plugins_support_is_set)]
514 l += [AND(KconfigCheck('self_protection', 'kspp', 'STACKLEAK_RUNTIME_DISABLE', 'is not set'),
516 gcc_plugins_support_is_set)]
517 l += [KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y')]
518 if arch in ('X86_64', 'ARM64'):
519 cfi_clang_is_set = KconfigCheck('self_protection', 'kspp', 'CFI_CLANG', 'y')
520 l += [cfi_clang_is_set]
521 l += [AND(KconfigCheck('self_protection', 'kspp', 'CFI_PERMISSIVE', 'is not set'),
523 if arch in ('X86_64', 'X86_32'):
524 l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '65536')]
525 l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU_DEFAULT_ON', 'y'),
526 iommu_support_is_set)]
527 if arch in ('ARM64', 'ARM'):
528 l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '32768')]
529 l += [KconfigCheck('self_protection', 'kspp', 'SYN_COOKIES', 'y')] # another reason?
531 l += [KconfigCheck('self_protection', 'kspp', 'SLS', 'y')] # vs CVE-2021-26341 in Straight-Line-Speculation
532 l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU_SVM', 'y'),
533 iommu_support_is_set)]
534 l += [AND(KconfigCheck('self_protection', 'kspp', 'AMD_IOMMU_V2', 'y'),
535 iommu_support_is_set)]
537 l += [KconfigCheck('self_protection', 'kspp', 'ARM64_SW_TTBR0_PAN', 'y')]
538 l += [KconfigCheck('self_protection', 'kspp', 'SHADOW_CALL_STACK', 'y')]
539 l += [KconfigCheck('self_protection', 'kspp', 'KASAN_HW_TAGS', 'y')]
541 l += [KconfigCheck('self_protection', 'kspp', 'PAGE_TABLE_ISOLATION', 'y')]
542 l += [KconfigCheck('self_protection', 'kspp', 'HIGHMEM64G', 'y')]
543 l += [KconfigCheck('self_protection', 'kspp', 'X86_PAE', 'y')]
544 l += [AND(KconfigCheck('self_protection', 'kspp', 'INTEL_IOMMU', 'y'),
545 iommu_support_is_set)]
547 # 'self_protection', 'clipos'
548 l += [KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set')]
551 if arch in ('X86_64', 'ARM64', 'X86_32'):
552 l += [KconfigCheck('security_policy', 'defconfig', 'SECURITY', 'y')] # and choose your favourite LSM
554 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY', 'y')] # and choose your favourite LSM
555 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_YAMA', 'y')]
556 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LANDLOCK', 'y')]
557 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_DISABLE', 'is not set')]
558 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_BOOTPARAM', 'is not set')]
559 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_SELINUX_DEVELOP', 'is not set')]
560 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LOCKDOWN_LSM', 'y')]
561 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_LOCKDOWN_LSM_EARLY', 'y')]
562 l += [KconfigCheck('security_policy', 'kspp', 'LOCK_DOWN_KERNEL_FORCE_CONFIDENTIALITY', 'y')]
563 l += [KconfigCheck('security_policy', 'kspp', 'SECURITY_WRITABLE_HOOKS', 'is not set')] # refers to SECURITY_SELINUX_DISABLE
565 # 'cut_attack_surface', 'defconfig'
566 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP', 'y')]
567 l += [KconfigCheck('cut_attack_surface', 'defconfig', 'SECCOMP_FILTER', 'y')]
568 l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'BPF_UNPRIV_DEFAULT_OFF', 'y'),
569 bpf_syscall_not_set)] # see unprivileged_bpf_disabled
570 if arch in ('X86_64', 'ARM64', 'X86_32'):
571 l += [OR(KconfigCheck('cut_attack_surface', 'defconfig', 'STRICT_DEVMEM', 'y'),
572 devmem_not_set)] # refers to LOCKDOWN
574 # 'cut_attack_surface', 'kspp'
575 l += [KconfigCheck('cut_attack_surface', 'kspp', 'SECURITY_DMESG_RESTRICT', 'y')]
576 l += [KconfigCheck('cut_attack_surface', 'kspp', 'ACPI_CUSTOM_METHOD', 'is not set')] # refers to LOCKDOWN
577 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_BRK', 'is not set')]
578 l += [KconfigCheck('cut_attack_surface', 'kspp', 'DEVKMEM', 'is not set')] # refers to LOCKDOWN
579 l += [KconfigCheck('cut_attack_surface', 'kspp', 'COMPAT_VDSO', 'is not set')]
580 l += [KconfigCheck('cut_attack_surface', 'kspp', 'BINFMT_MISC', 'is not set')]
581 l += [KconfigCheck('cut_attack_surface', 'kspp', 'INET_DIAG', 'is not set')]
582 l += [KconfigCheck('cut_attack_surface', 'kspp', 'KEXEC', 'is not set')] # refers to LOCKDOWN
583 l += [KconfigCheck('cut_attack_surface', 'kspp', 'PROC_KCORE', 'is not set')] # refers to LOCKDOWN
584 l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_PTYS', 'is not set')]
585 l += [KconfigCheck('cut_attack_surface', 'kspp', 'HIBERNATION', 'is not set')] # refers to LOCKDOWN
586 l += [KconfigCheck('cut_attack_surface', 'kspp', 'IA32_EMULATION', 'is not set')]
587 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_X32', 'is not set')]
588 l += [KconfigCheck('cut_attack_surface', 'kspp', 'MODIFY_LDT_SYSCALL', 'is not set')]
589 l += [KconfigCheck('cut_attack_surface', 'kspp', 'OABI_COMPAT', 'is not set')]
590 l += [KconfigCheck('cut_attack_surface', 'kspp', 'X86_MSR', 'is not set')] # refers to LOCKDOWN
591 l += [modules_not_set]
592 l += [devmem_not_set]
593 l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'IO_STRICT_DEVMEM', 'y'),
594 devmem_not_set)] # refers to LOCKDOWN
595 l += [AND(KconfigCheck('cut_attack_surface', 'kspp', 'LDISC_AUTOLOAD', 'is not set'),
596 KconfigCheck('cut_attack_surface', 'kspp', 'LDISC_AUTOLOAD', 'is present'))]
598 l += [KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y')] # 'vsyscall=none'
600 l += [OR(KconfigCheck('cut_attack_surface', 'kspp', 'STRICT_DEVMEM', 'y'),
601 devmem_not_set)] # refers to LOCKDOWN
603 # 'cut_attack_surface', 'grsec'
604 l += [KconfigCheck('cut_attack_surface', 'grsec', 'ZSMALLOC_STAT', 'is not set')]
605 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PAGE_OWNER', 'is not set')]
606 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_KMEMLEAK', 'is not set')]
607 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BINFMT_AOUT', 'is not set')]
608 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KPROBE_EVENTS', 'is not set')]
609 l += [KconfigCheck('cut_attack_surface', 'grsec', 'UPROBE_EVENTS', 'is not set')]
610 l += [KconfigCheck('cut_attack_surface', 'grsec', 'GENERIC_TRACER', 'is not set')] # refers to LOCKDOWN
611 l += [KconfigCheck('cut_attack_surface', 'grsec', 'FUNCTION_TRACER', 'is not set')]
612 l += [KconfigCheck('cut_attack_surface', 'grsec', 'STACK_TRACER', 'is not set')]
613 l += [KconfigCheck('cut_attack_surface', 'grsec', 'HIST_TRIGGERS', 'is not set')]
614 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BLK_DEV_IO_TRACE', 'is not set')]
615 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_VMCORE', 'is not set')]
616 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROC_PAGE_MONITOR', 'is not set')]
617 l += [KconfigCheck('cut_attack_surface', 'grsec', 'USELIB', 'is not set')]
618 l += [KconfigCheck('cut_attack_surface', 'grsec', 'CHECKPOINT_RESTORE', 'is not set')]
619 l += [KconfigCheck('cut_attack_surface', 'grsec', 'USERFAULTFD', 'is not set')]
620 l += [KconfigCheck('cut_attack_surface', 'grsec', 'HWPOISON_INJECT', 'is not set')]
621 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MEM_SOFT_DIRTY', 'is not set')]
622 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEVPORT', 'is not set')] # refers to LOCKDOWN
623 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set')] # refers to LOCKDOWN
624 l += [KconfigCheck('cut_attack_surface', 'grsec', 'NOTIFIER_ERROR_INJECTION', 'is not set')]
625 l += [KconfigCheck('cut_attack_surface', 'grsec', 'FAIL_FUTEX', 'is not set')]
626 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PUNIT_ATOM_DEBUG', 'is not set')]
627 l += [KconfigCheck('cut_attack_surface', 'grsec', 'ACPI_CONFIGFS', 'is not set')]
628 l += [KconfigCheck('cut_attack_surface', 'grsec', 'EDAC_DEBUG', 'is not set')]
629 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DRM_I915_DEBUG', 'is not set')]
630 l += [KconfigCheck('cut_attack_surface', 'grsec', 'BCACHE_CLOSURES_DEBUG', 'is not set')]
631 l += [KconfigCheck('cut_attack_surface', 'grsec', 'DVB_C8SECTPFE', 'is not set')]
632 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_SLRAM', 'is not set')]
633 l += [KconfigCheck('cut_attack_surface', 'grsec', 'MTD_PHRAM', 'is not set')]
634 l += [KconfigCheck('cut_attack_surface', 'grsec', 'IO_URING', 'is not set')]
635 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCMP', 'is not set')]
636 l += [KconfigCheck('cut_attack_surface', 'grsec', 'RSEQ', 'is not set')]
637 l += [KconfigCheck('cut_attack_surface', 'grsec', 'LATENCYTOP', 'is not set')]
638 l += [KconfigCheck('cut_attack_surface', 'grsec', 'KCOV', 'is not set')]
639 l += [KconfigCheck('cut_attack_surface', 'grsec', 'PROVIDE_OHCI1394_DMA_INIT', 'is not set')]
640 l += [KconfigCheck('cut_attack_surface', 'grsec', 'SUNRPC_DEBUG', 'is not set')]
641 l += [AND(KconfigCheck('cut_attack_surface', 'grsec', 'PTDUMP_DEBUGFS', 'is not set'),
642 KconfigCheck('cut_attack_surface', 'grsec', 'X86_PTDUMP', 'is not set'))]
644 # 'cut_attack_surface', 'maintainer'
645 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'DRM_LEGACY', 'is not set')] # recommended by Daniel Vetter in /issues/38
646 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'FB', 'is not set')] # recommended by Daniel Vetter in /issues/38
647 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'VT', 'is not set')] # recommended by Daniel Vetter in /issues/38
648 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD', 'is not set')] # recommended by Denis Efremov in /pull/54
649 l += [KconfigCheck('cut_attack_surface', 'maintainer', 'BLK_DEV_FD_RAWCMD', 'is not set')] # recommended by Denis Efremov in /pull/62
651 # 'cut_attack_surface', 'grapheneos'
652 l += [KconfigCheck('cut_attack_surface', 'grapheneos', 'AIO', 'is not set')]
654 # 'cut_attack_surface', 'clipos'
655 l += [KconfigCheck('cut_attack_surface', 'clipos', 'STAGING', 'is not set')]
656 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KSM', 'is not set')] # to prevent FLUSH+RELOAD attack
657 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KALLSYMS', 'is not set')]
658 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_VSYSCALL_EMULATION', 'is not set')]
659 l += [KconfigCheck('cut_attack_surface', 'clipos', 'MAGIC_SYSRQ', 'is not set')]
660 l += [KconfigCheck('cut_attack_surface', 'clipos', 'KEXEC_FILE', 'is not set')] # refers to LOCKDOWN (permissive)
661 l += [KconfigCheck('cut_attack_surface', 'clipos', 'USER_NS', 'is not set')] # user.max_user_namespaces=0
662 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_CPUID', 'is not set')]
663 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_IOPL_IOPERM', 'is not set')] # refers to LOCKDOWN
664 l += [KconfigCheck('cut_attack_surface', 'clipos', 'ACPI_TABLE_UPGRADE', 'is not set')] # refers to LOCKDOWN
665 l += [KconfigCheck('cut_attack_surface', 'clipos', 'EFI_CUSTOM_SSDT_OVERLAYS', 'is not set')]
666 l += [KconfigCheck('cut_attack_surface', 'clipos', 'COREDUMP', 'is not set')] # cut userspace attack surface
667 # l += [KconfigCheck('cut_attack_surface', 'clipos', 'IKCONFIG', 'is not set')] # no, IKCONFIG is needed for this check :)
668 if arch in ('X86_64', 'X86_32'):
669 l += [KconfigCheck('cut_attack_surface', 'clipos', 'X86_INTEL_TSX_MODE_OFF', 'y')] # tsx=off
671 # 'cut_attack_surface', 'lockdown'
672 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'EFI_TEST', 'is not set')] # refers to LOCKDOWN
673 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'MMIOTRACE_TEST', 'is not set')] # refers to LOCKDOWN
674 l += [KconfigCheck('cut_attack_surface', 'lockdown', 'KPROBES', 'is not set')] # refers to LOCKDOWN
675 l += [bpf_syscall_not_set] # refers to LOCKDOWN
677 # 'cut_attack_surface', 'my'
678 l += [KconfigCheck('cut_attack_surface', 'my', 'MMIOTRACE', 'is not set')] # refers to LOCKDOWN (permissive)
679 l += [KconfigCheck('cut_attack_surface', 'my', 'LIVEPATCH', 'is not set')]
680 l += [KconfigCheck('cut_attack_surface', 'my', 'IP_DCCP', 'is not set')]
681 l += [KconfigCheck('cut_attack_surface', 'my', 'IP_SCTP', 'is not set')]
682 l += [KconfigCheck('cut_attack_surface', 'my', 'FTRACE', 'is not set')] # refers to LOCKDOWN
683 l += [KconfigCheck('cut_attack_surface', 'my', 'VIDEO_VIVID', 'is not set')]
684 l += [KconfigCheck('cut_attack_surface', 'my', 'INPUT_EVBUG', 'is not set')] # Can be used as a keylogger
685 l += [KconfigCheck('cut_attack_surface', 'my', 'KGDB', 'is not set')]
686 l += [OR(KconfigCheck('cut_attack_surface', 'my', 'TRIM_UNUSED_KSYMS', 'y'),
690 if arch in ('X86_64', 'ARM64', 'X86_32'):
691 l += [KconfigCheck('harden_userspace', 'defconfig', 'INTEGRITY', 'y')]
693 l += [KconfigCheck('harden_userspace', 'my', 'INTEGRITY', 'y')]
695 l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_PTR_AUTH', 'y')]
696 l += [KconfigCheck('harden_userspace', 'defconfig', 'ARM64_BTI', 'y')]
697 if arch in ('ARM', 'X86_32'):
698 l += [KconfigCheck('harden_userspace', 'defconfig', 'VMSPLIT_3G', 'y')]
699 if arch in ('X86_64', 'ARM64'):
700 l += [KconfigCheck('harden_userspace', 'clipos', 'ARCH_MMAP_RND_BITS', '32')]
701 if arch in ('X86_32', 'ARM'):
702 l += [KconfigCheck('harden_userspace', 'my', 'ARCH_MMAP_RND_BITS', '16')]
705 def add_cmdline_checks(l, arch):
706 # Calling the CmdlineCheck class constructor:
707 # CmdlineCheck(reason, decision, name, expected)
709 # [!] Don't add CmdlineChecks in add_kconfig_checks() to avoid wrong results
710 # when the tool doesn't check the cmdline.
712 # [!] Make sure that values of the options in CmdlineChecks need normalization.
713 # For more info see normalize_cmdline_options().
715 # A common pattern for checking the 'param_x' cmdline parameter
716 # that __overrides__ the 'PARAM_X_DEFAULT' kconfig option:
717 # l += [OR(CmdlineCheck(reason, decision, 'param_x', '1'),
718 # AND(KconfigCheck(reason, decision, 'PARAM_X_DEFAULT_ON', 'y'),
719 # CmdlineCheck(reason, decision, 'param_x, 'is not set')))]
721 # Here we don't check the kconfig options or minimal kernel version
722 # required for the cmdline parameters. That would make the checks
723 # very complex and not give a 100% guarantee anyway.
725 # 'self_protection', 'defconfig'
726 l += [CmdlineCheck('self_protection', 'defconfig', 'nosmep', 'is not set')]
727 l += [CmdlineCheck('self_protection', 'defconfig', 'nosmap', 'is not set')]
728 l += [CmdlineCheck('self_protection', 'defconfig', 'nokaslr', 'is not set')]
729 l += [CmdlineCheck('self_protection', 'defconfig', 'nopti', 'is not set')]
730 l += [CmdlineCheck('self_protection', 'defconfig', 'nospectre_v1', 'is not set')]
731 l += [CmdlineCheck('self_protection', 'defconfig', 'nospectre_v2', 'is not set')]
732 l += [CmdlineCheck('self_protection', 'defconfig', 'nospec_store_bypass_disable', 'is not set')]
733 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'mitigations', 'is not off'),
734 CmdlineCheck('self_protection', 'defconfig', 'mitigations', 'is not set'))]
735 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'spectre_v2', 'is not off'),
736 CmdlineCheck('self_protection', 'defconfig', 'spectre_v2', 'is not set'))]
737 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'spectre_v2_user', 'is not off'),
738 CmdlineCheck('self_protection', 'defconfig', 'spectre_v2_user', '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'))]
741 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'l1tf', 'is not off'),
742 CmdlineCheck('self_protection', 'defconfig', 'l1tf', 'is not set'))]
743 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'mds', 'is not off'),
744 CmdlineCheck('self_protection', 'defconfig', 'mds', 'is not set'))]
745 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'tsx_async_abort', 'is not off'),
746 CmdlineCheck('self_protection', 'defconfig', 'tsx_async_abort', 'is not set'))]
747 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'srbds', 'is not off'),
748 CmdlineCheck('self_protection', 'defconfig', 'srbds', 'is not set'))]
749 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'mmio_stale_data', 'is not off'),
750 CmdlineCheck('self_protection', 'defconfig', 'mmio_stale_data', 'is not set'))]
751 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'retbleed', 'is not off'),
752 CmdlineCheck('self_protection', 'defconfig', 'retbleed', 'is not set'))]
754 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', 'full'),
755 AND(KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y'),
756 CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set')))]
758 l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', '1'),
759 CmdlineCheck('self_protection', 'defconfig', 'rodata', 'is not set'))]
761 # 'self_protection', 'kspp'
762 l += [CmdlineCheck('self_protection', 'kspp', 'nosmt', 'is present')]
763 l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', '1'),
764 AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_ALLOC_DEFAULT_ON', 'y'),
765 CmdlineCheck('self_protection', 'kspp', 'init_on_alloc', 'is not set')))]
766 l += [OR(CmdlineCheck('self_protection', 'kspp', 'init_on_free', '1'),
767 AND(KconfigCheck('self_protection', 'kspp', 'INIT_ON_FREE_DEFAULT_ON', 'y'),
768 CmdlineCheck('self_protection', 'kspp', 'init_on_free', 'is not set')),
769 AND(CmdlineCheck('self_protection', 'kspp', 'page_poison', '1'),
770 KconfigCheck('self_protection', 'kspp', 'PAGE_POISONING_ZERO', 'y'),
771 CmdlineCheck('self_protection', 'kspp', 'slub_debug', 'P')))]
772 l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_nomerge', 'is present'),
773 AND(KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set'),
774 CmdlineCheck('self_protection', 'kspp', 'slab_merge', 'is not set')))]
775 l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.strict', '1'),
776 AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_DMA_STRICT', 'y'),
777 CmdlineCheck('self_protection', 'kspp', 'iommu.strict', 'is not set')))]
778 l += [OR(CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', '0'),
779 AND(KconfigCheck('self_protection', 'kspp', 'IOMMU_DEFAULT_PASSTHROUGH', 'is not set'),
780 CmdlineCheck('self_protection', 'kspp', 'iommu.passthrough', 'is not set')))]
781 # The cmdline checks compatible with the kconfig recommendations of the KSPP project...
782 l += [OR(CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', '1'),
783 AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY', 'y'),
784 CmdlineCheck('self_protection', 'kspp', 'hardened_usercopy', 'is not set')))]
785 l += [OR(CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', '0'),
786 AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_FALLBACK', 'is not set'),
787 CmdlineCheck('self_protection', 'kspp', 'slab_common.usercopy_fallback', 'is not set')))]
789 if arch in ('X86_64', 'ARM64', 'X86_32'):
790 l += [OR(CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', '1'),
791 AND(KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y'),
792 CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', 'is not set')))]
793 if arch in ('X86_64', 'X86_32'):
794 l += [AND(CmdlineCheck('self_protection', 'kspp', 'pti', 'on'),
795 CmdlineCheck('self_protection', 'defconfig', 'nopti', 'is not set'))]
797 # 'self_protection', 'clipos'
798 l += [CmdlineCheck('self_protection', 'clipos', 'page_alloc.shuffle', '1')]
800 # 'cut_attack_surface', 'kspp'
802 l += [OR(CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'none'),
803 AND(KconfigCheck('cut_attack_surface', 'kspp', 'LEGACY_VSYSCALL_NONE', 'y'),
804 CmdlineCheck('cut_attack_surface', 'kspp', 'vsyscall', 'is not set')))]
806 # 'cut_attack_surface', 'grsec'
807 # The cmdline checks compatible with the kconfig options disabled by grsecurity...
808 l += [OR(CmdlineCheck('cut_attack_surface', 'grsec', 'debugfs', 'off'),
809 KconfigCheck('cut_attack_surface', 'grsec', 'DEBUG_FS', 'is not set'))] # ... the end
812 def print_unknown_options(checklist, parsed_options):
816 if o1.type != 'complex':
817 known_options.append(o1.name)
820 if o2.type != 'complex':
821 if hasattr(o2, 'name'):
822 known_options.append(o2.name)
825 assert(o3.type != 'complex'), \
826 'unexpected ComplexOptCheck inside {}'.format(o2.name)
827 if hasattr(o3, 'name'):
828 known_options.append(o3.name)
830 for option, value in parsed_options.items():
831 if option not in known_options:
832 print('[?] No check for option {} ({})'.format(option, value))
835 def print_checklist(mode, checklist, with_results):
839 output.append(o.json_dump(with_results))
840 print(json.dumps(output))
847 print('=' * sep_line_len)
848 print('{:^40}|{:^7}|{:^12}|{:^10}|{:^18}'.format('option name', 'type', 'desired val', 'decision', 'reason'), end='')
850 print('| {}'.format('check result'), end='')
852 print('=' * sep_line_len)
855 for opt in checklist:
857 if mode == 'show_ok':
858 if not opt.result.startswith('OK'):
860 if mode == 'show_fail':
861 if not opt.result.startswith('FAIL'):
863 opt.table_print(mode, with_results)
865 if mode == 'verbose':
866 print('-' * sep_line_len)
871 fail_count = len(list(filter(lambda opt: opt.result.startswith('FAIL'), checklist)))
873 ok_count = len(list(filter(lambda opt: opt.result.startswith('OK'), checklist)))
875 if mode == 'show_ok':
876 fail_suppressed = ' (suppressed in output)'
877 if mode == 'show_fail':
878 ok_suppressed = ' (suppressed in output)'
880 print('[+] Config check is finished: \'OK\' - {}{} / \'FAIL\' - {}{}'.format(ok_count, ok_suppressed, fail_count, fail_suppressed))
883 def populate_simple_opt_with_data(opt, data, data_type):
884 assert(opt.type != 'complex'), \
885 'unexpected ComplexOptCheck "{}"'.format(opt.name)
886 assert(opt.type in SIMPLE_OPTION_TYPES), \
887 'invalid opt type "{}"'.format(opt.type)
888 assert(data_type in SIMPLE_OPTION_TYPES), \
889 'invalid data type "{}"'.format(data_type)
891 if data_type != opt.type:
894 if data_type in ('kconfig', 'cmdline'):
895 opt.state = data.get(opt.name, None)
897 assert(data_type == 'version'), \
898 'unexpected data type "{}"'.format(data_type)
902 def populate_opt_with_data(opt, data, data_type):
903 if opt.type == 'complex':
905 if o.type == 'complex':
906 # Recursion for nested ComplexOptCheck objects
907 populate_opt_with_data(o, data, data_type)
909 populate_simple_opt_with_data(o, data, data_type)
911 assert(opt.type in ('kconfig', 'cmdline')), \
912 'bad type "{}" for a simple check'.format(opt.type)
913 populate_simple_opt_with_data(opt, data, data_type)
916 def populate_with_data(checklist, data, data_type):
917 for opt in checklist:
918 populate_opt_with_data(opt, data, data_type)
921 def perform_checks(checklist):
922 for opt in checklist:
926 def parse_kconfig_file(parsed_options, fname):
927 with open(fname, 'r') as f:
928 opt_is_on = re.compile("CONFIG_[a-zA-Z0-9_]*=[a-zA-Z0-9_\"]*")
929 opt_is_off = re.compile("# CONFIG_[a-zA-Z0-9_]* is not set")
931 for line in f.readlines():
936 if opt_is_on.match(line):
937 option, value = line.split('=', 1)
938 if value == 'is not set':
939 sys.exit('[!] ERROR: bad enabled kconfig option "{}"'.format(line))
940 elif opt_is_off.match(line):
941 option, value = line[2:].split(' ', 1)
942 if value != 'is not set':
943 sys.exit('[!] ERROR: bad disabled kconfig option "{}"'.format(line))
945 if option in parsed_options:
946 sys.exit('[!] ERROR: kconfig option "{}" exists multiple times'.format(line))
949 parsed_options[option] = value
952 def normalize_cmdline_options(option, value):
953 # Don't normalize the cmdline option values if
954 # the Linux kernel doesn't use kstrtobool() for them
955 if option == 'debugfs':
956 # See debugfs_kernel() in fs/debugfs/inode.c
958 if option == 'mitigations':
959 # See mitigations_parse_cmdline() in kernel/cpu.c
962 # See pti_check_boottime_disable() in arch/x86/mm/pti.c
964 if option == 'spectre_v2':
965 # See spectre_v2_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
967 if option == 'spectre_v2_user':
968 # See spectre_v2_parse_user_cmdline() in arch/x86/kernel/cpu/bugs.c
970 if option == 'spec_store_bypass_disable':
971 # See ssb_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
974 # See l1tf_cmdline() in arch/x86/kernel/cpu/bugs.c
977 # See mds_cmdline() in arch/x86/kernel/cpu/bugs.c
979 if option == 'tsx_async_abort':
980 # See tsx_async_abort_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
982 if option == 'srbds':
983 # See srbds_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
985 if option == 'mmio_stale_data':
986 # See mmio_stale_data_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
988 if option == 'retbleed':
989 # See retbleed_parse_cmdline() in arch/x86/kernel/cpu/bugs.c
992 # Implement a limited part of the kstrtobool() logic
993 if value in ('1', 'on', 'On', 'ON', 'y', 'Y', 'yes', 'Yes', 'YES'):
995 if value in ('0', 'off', 'Off', 'OFF', 'n', 'N', 'no', 'No', 'NO'):
998 # Preserve unique values
1002 def parse_cmdline_file(parsed_options, fname):
1003 with open(fname, 'r') as f:
1009 sys.exit('[!] ERROR: more than one line in "{}"'.format(fname))
1013 name, value = opt.split('=', 1)
1016 value = '' # '' is not None
1017 value = normalize_cmdline_options(name, value)
1018 parsed_options[name] = value
1023 # * verbose mode for
1024 # - reporting about unknown kernel options in the kconfig
1025 # - verbose printing of ComplexOptCheck items
1026 # * json mode for printing the results in JSON format
1027 report_modes = ['verbose', 'json', 'show_ok', 'show_fail']
1028 supported_archs = ['X86_64', 'X86_32', 'ARM64', 'ARM']
1029 parser = ArgumentParser(prog='kconfig-hardened-check',
1030 description='A tool for checking the security hardening options of the Linux kernel')
1031 parser.add_argument('--version', action='version', version='%(prog)s ' + __version__)
1032 parser.add_argument('-p', '--print', choices=supported_archs,
1033 help='print security hardening preferences for the selected architecture')
1034 parser.add_argument('-c', '--config',
1035 help='check the kernel kconfig file against these preferences')
1036 parser.add_argument('-l', '--cmdline',
1037 help='check the kernel cmdline file against these preferences')
1038 parser.add_argument('-m', '--mode', choices=report_modes,
1039 help='choose the report mode')
1040 args = parser.parse_args()
1046 print('[+] Special report mode: {}'.format(mode))
1048 config_checklist = []
1052 sys.exit('[!] ERROR: --config and --print can\'t be used together')
1055 print('[+] Kconfig file to check: {}'.format(args.config))
1057 print('[+] Kernel cmdline file to check: {}'.format(args.cmdline))
1059 arch, msg = detect_arch(args.config, supported_archs)
1061 sys.exit('[!] ERROR: {}'.format(msg))
1063 print('[+] Detected architecture: {}'.format(arch))
1065 kernel_version, msg = detect_kernel_version(args.config)
1066 if not kernel_version:
1067 sys.exit('[!] ERROR: {}'.format(msg))
1069 print('[+] Detected kernel version: {}.{}'.format(kernel_version[0], kernel_version[1]))
1071 compiler, msg = detect_compiler(args.config)
1074 print('[+] Detected compiler: {}'.format(compiler))
1076 print('[-] Can\'t detect the compiler: {}'.format(msg))
1078 # add relevant kconfig checks to the checklist
1079 add_kconfig_checks(config_checklist, arch)
1082 # add relevant cmdline checks to the checklist
1083 add_cmdline_checks(config_checklist, arch)
1085 # populate the checklist with the parsed kconfig data
1086 parsed_kconfig_options = OrderedDict()
1087 parse_kconfig_file(parsed_kconfig_options, args.config)
1088 populate_with_data(config_checklist, parsed_kconfig_options, 'kconfig')
1089 populate_with_data(config_checklist, kernel_version, 'version')
1092 # populate the checklist with the parsed kconfig data
1093 parsed_cmdline_options = OrderedDict()
1094 parse_cmdline_file(parsed_cmdline_options, args.cmdline)
1095 populate_with_data(config_checklist, parsed_cmdline_options, 'cmdline')
1097 # now everything is ready for performing the checks
1098 perform_checks(config_checklist)
1100 # finally print the results
1101 if mode == 'verbose':
1102 print_unknown_options(config_checklist, parsed_kconfig_options)
1103 print_checklist(mode, config_checklist, True)
1107 sys.exit('[!] ERROR: checking cmdline doesn\'t work without checking kconfig')
1110 if mode in ('show_ok', 'show_fail'):
1111 sys.exit('[!] ERROR: wrong mode "{}" for --print'.format(mode))
1113 add_kconfig_checks(config_checklist, arch)
1114 add_cmdline_checks(config_checklist, arch)
1116 print('[+] Printing kernel security hardening preferences for {}...'.format(arch))
1117 print_checklist(mode, config_checklist, False)