Add the BLK_DEV_WRITE_MOUNTED/bdev_allow_write_mounted check

[kconfig-hardened-check.git] / kernel_hardening_checker / checks.py

diff --git a/kernel_hardening_checker/checks.py b/kernel_hardening_checker/checks.py
index 99e8810fb324a4bc417b6a875d656b6bfb0af6f2..94cf9504493fe0634465dfd07f31a78b9f19421e 100644 (file)
--- a/kernel_hardening_checker/checks.py
+++ b/kernel_hardening_checker/checks.py
@@ -26,7 +26,6 @@ def add_kconfig_checks(l, arch):
     efi_not_set = KconfigCheck('-', '-', 'EFI', 'is not set')
     cc_is_gcc = KconfigCheck('-', '-', 'CC_IS_GCC', 'y') # exists since v4.18
     cc_is_clang = KconfigCheck('-', '-', 'CC_IS_CLANG', 'y') # exists since v4.18
-    gcc_plugins_support_is_set = KconfigCheck('-', '-', 'GCC_PLUGINS', 'y')
 
     modules_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'MODULES', 'is not set') # radical, but may be useful in some cases
     devmem_not_set = KconfigCheck('cut_attack_surface', 'kspp', 'DEVMEM', 'is not set') # refers to LOCKDOWN
@@ -139,7 +138,8 @@ def add_kconfig_checks(l, arch):
              VersionCheck((6, 6, 8)))] # DEBUG_CREDENTIALS was dropped in v6.6.8
     l += [OR(KconfigCheck('self_protection', 'kspp', 'DEBUG_NOTIFIERS', 'y'),
              AND(cfi_clang_is_set,
-                 cfi_clang_permissive_not_set))]
+                 cfi_clang_permissive_not_set,
+                 cc_is_clang))]
     l += [OR(KconfigCheck('self_protection', 'kspp', 'SCHED_STACK_END_CHECK', 'y'),
              vmap_stack_is_set)]
     kfence_is_set = KconfigCheck('self_protection', 'kspp', 'KFENCE', 'y')
@@ -159,7 +159,6 @@ def add_kconfig_checks(l, arch):
     l += [AND(KconfigCheck('self_protection', 'kspp', 'HARDENED_USERCOPY_PAGESPAN', 'is not set'),
               hardened_usercopy_is_set)] # this debugging for HARDENED_USERCOPY is not needed for security
     l += [AND(KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_LATENT_ENTROPY', 'y'),
-              gcc_plugins_support_is_set,
               cc_is_gcc)]
     l += [OR(KconfigCheck('self_protection', 'kspp', 'MODULE_SIG', 'y'),
              modules_not_set)]
@@ -199,21 +198,20 @@ def add_kconfig_checks(l, arch):
     if arch in ('X86_64', 'ARM64', 'X86_32'):
         stackleak_is_set = KconfigCheck('self_protection', 'kspp', 'GCC_PLUGIN_STACKLEAK', 'y')
         l += [AND(stackleak_is_set,
-                  gcc_plugins_support_is_set,
                   cc_is_gcc)]
         l += [AND(KconfigCheck('self_protection', 'kspp', 'STACKLEAK_METRICS', 'is not set'),
                   stackleak_is_set,
-                  gcc_plugins_support_is_set,
                   cc_is_gcc)]
         l += [AND(KconfigCheck('self_protection', 'kspp', 'STACKLEAK_RUNTIME_DISABLE', 'is not set'),
                   stackleak_is_set,
-                  gcc_plugins_support_is_set,
                   cc_is_gcc)]
         l += [KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y')]
     if arch in ('X86_64', 'ARM64'):
-        l += [cfi_clang_is_set]
+        l += [AND(cfi_clang_is_set,
+                  cc_is_clang)]
         l += [AND(cfi_clang_permissive_not_set,
-                  cfi_clang_is_set)]
+                  cfi_clang_is_set,
+                  cc_is_clang)]
     if arch in ('X86_64', 'X86_32'):
         l += [KconfigCheck('self_protection', 'kspp', 'HW_RANDOM_TPM', 'y')]
         l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '65536')]
@@ -397,9 +395,11 @@ def add_kconfig_checks(l, arch):
     l += [KconfigCheck('cut_attack_surface', 'a13xp0p0v', 'KGDB', 'is not set')]
     l += [KconfigCheck('cut_attack_surface', 'a13xp0p0v', 'CORESIGHT', 'is not set')]
     l += [KconfigCheck('cut_attack_surface', 'a13xp0p0v', 'XFS_SUPPORT_V4', 'is not set')]
+    l += [KconfigCheck('cut_attack_surface', 'a13xp0p0v', 'MODULE_FORCE_LOAD', 'is not set')]
+    l += [KconfigCheck('cut_attack_surface', 'a13xp0p0v', 'BLK_DEV_WRITE_MOUNTED', 'is not set')]
     l += [OR(KconfigCheck('cut_attack_surface', 'a13xp0p0v', 'TRIM_UNUSED_KSYMS', 'y'),
              modules_not_set)]
-    l += [KconfigCheck('cut_attack_surface', 'a13xp0p0v', 'MODULE_FORCE_LOAD', 'is not set')]
+
 
     # 'harden_userspace'
     if arch == 'ARM64':
@@ -409,6 +409,8 @@ def add_kconfig_checks(l, arch):
         l += [KconfigCheck('harden_userspace', 'defconfig', 'VMSPLIT_3G', 'y')]
     l += [KconfigCheck('harden_userspace', 'clipos', 'COREDUMP', 'is not set')]
     l += [KconfigCheck('harden_userspace', 'a13xp0p0v', 'ARCH_MMAP_RND_BITS', 'MAX')] # 'MAX' value is refined using ARCH_MMAP_RND_BITS_MAX
+    if arch == 'X86_64':
+        l += [KconfigCheck('harden_userspace', 'a13xp0p0v', 'X86_USER_SHADOW_STACK', 'y')]
 
 
 def add_cmdline_checks(l, arch):
@@ -577,6 +579,9 @@ def add_cmdline_checks(l, arch):
 
     # 'cut_attack_surface', 'a13xp0p0v'
     l += [CmdlineCheck('cut_attack_surface', 'a13xp0p0v', 'sysrq_always_enabled', 'is not set')]
+    l += [OR(CmdlineCheck('cut_attack_surface', 'a13xp0p0v', 'bdev_allow_write_mounted', '0'),
+             AND(KconfigCheck('cut_attack_surface', 'a13xp0p0v', 'BLK_DEV_WRITE_MOUNTED', 'is not set'),
+                 CmdlineCheck('cut_attack_surface', 'a13xp0p0v', 'bdev_allow_write_mounted', 'is not set')))]
     if arch == 'X86_64':
         l += [OR(CmdlineCheck('cut_attack_surface', 'a13xp0p0v', 'ia32_emulation', '0'),
                  KconfigCheck('cut_attack_surface', 'kspp', 'IA32_EMULATION', 'is not set'),
@@ -651,7 +656,7 @@ def add_sysctl_checks(l, _arch):
     l += [SysctlCheck('cut_attack_surface', 'kspp', 'kernel.dmesg_restrict', '1')]
     l += [SysctlCheck('cut_attack_surface', 'kspp', 'kernel.perf_event_paranoid', '3')] # with a custom patch, see https://lwn.net/Articles/696216/
     l += [SysctlCheck('cut_attack_surface', 'kspp', 'kernel.kexec_load_disabled', '1')]
-    l += [SysctlCheck('cut_attack_surface', 'kspp', 'user.max_user_namespaces', '0')]
+    l += [SysctlCheck('cut_attack_surface', 'kspp', 'user.max_user_namespaces', '0')] # may break the upower daemon in Ubuntu
     l += [SysctlCheck('cut_attack_surface', 'kspp', 'dev.tty.ldisc_autoload', '0')]
     l += [SysctlCheck('cut_attack_surface', 'kspp', 'kernel.unprivileged_bpf_disabled', '1')]
     l += [SysctlCheck('cut_attack_surface', 'kspp', 'kernel.kptr_restrict', '2')]