Merge branch 'master' into typing

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

diff --git a/kernel_hardening_checker/checks.py b/kernel_hardening_checker/checks.py
index 9f48d5849f6a675a3d560ec0138a2ad8da44e956..193b374c8ae444628fec525e071134367b5228cb 100644 (file)
--- a/kernel_hardening_checker/checks.py
+++ b/kernel_hardening_checker/checks.py
@@ -14,7 +14,7 @@ This module contains knowledge for checks.
 from .engine import KconfigCheck, CmdlineCheck, SysctlCheck, VersionCheck, OR, AND
 
 
-def add_kconfig_checks(l, arch):
+def add_kconfig_checks(l, arch: str):
     assert(arch), 'empty arch'
 
     # Calling the KconfigCheck class constructor:
@@ -422,7 +422,7 @@ def add_kconfig_checks(l, arch):
         l += [KconfigCheck('harden_userspace', 'a13xp0p0v', 'X86_USER_SHADOW_STACK', 'y')]
 
 
-def add_cmdline_checks(l, arch):
+def add_cmdline_checks(l, arch: str):
     assert(arch), 'empty arch'
 
     # Calling the CmdlineCheck class constructor:
@@ -630,7 +630,7 @@ no_kstrtobool_options = [
 ]
 
 
-def normalize_cmdline_options(option, value):
+def normalize_cmdline_options(option: str, value: str) -> str:
     # Don't normalize the cmdline option values if
     # the Linux kernel doesn't use kstrtobool() for them
     if option in no_kstrtobool_options:
@@ -657,35 +657,40 @@ def normalize_cmdline_options(option, value):
 #    kernel.warn_limit (think about a proper value)
 #    net.ipv4.tcp_syncookies=1 (?)
 
-def add_sysctl_checks(l, _arch):
+def add_sysctl_checks(l, _arch: str):
 # This function may be called with arch=None
 
 # Calling the SysctlCheck class constructor:
 #   SysctlCheck(reason, decision, name, expected)
 
-    # use an omnipresent config symbol to see if we have a config file
-    have_config_file = KconfigCheck('-', '-', 'DEFAULT_INIT', 'is present')
+    # Use an omnipresent kconfig symbol to see if we have a kconfig file for checking
+    have_kconfig = KconfigCheck('-', '-', 'LOCALVERSION', 'is present')
+
     l += [OR(SysctlCheck('self_protection', 'kspp', 'net.core.bpf_jit_harden', '2'),
-             AND(KconfigCheck('cut_attack_surface', 'kspp', 'BPF_JIT', 'is not set'),
-                 have_config_file))]
+             AND(KconfigCheck('-', '-', 'BPF_JIT', 'is not set'),
+                 have_kconfig))]
 
     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 += [OR(SysctlCheck('cut_attack_surface', 'kspp', 'kernel.kexec_load_disabled', '1'),
-             AND(KconfigCheck('cut_attack_surfice', 'kspp', 'KEXEC_CORE', 'is not set'),
-                 have_config_file))]
     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 += [OR(SysctlCheck('cut_attack_surface', 'kspp', 'kernel.unprivileged_bpf_disabled', '1'),
-             AND(KconfigCheck('cut_attack_surface', 'lockdown', 'BPF_SYSCALL', 'is not set'),
-                 have_config_file))]
     l += [SysctlCheck('cut_attack_surface', 'kspp', 'kernel.kptr_restrict', '2')]
     l += [SysctlCheck('cut_attack_surface', 'kspp', 'dev.tty.legacy_tiocsti', '0')]
-    l += [SysctlCheck('cut_attack_surface', 'kspp', 'vm.unprivileged_userfaultfd', '0')]
+    l += [OR(SysctlCheck('cut_attack_surface', 'kspp', 'kernel.kexec_load_disabled', '1'),
+             AND(KconfigCheck('-', '-', 'KEXEC_CORE', 'is not set'),
+                 have_kconfig))]
+    l += [OR(SysctlCheck('cut_attack_surface', 'kspp', 'kernel.unprivileged_bpf_disabled', '1'),
+             AND(KconfigCheck('cut_attack_surface', 'lockdown', 'BPF_SYSCALL', 'is not set'),
+                 have_kconfig))]
+    l += [OR(SysctlCheck('cut_attack_surface', 'kspp', 'vm.unprivileged_userfaultfd', '0'),
+             AND(KconfigCheck('cut_attack_surface', 'grsec', 'USERFAULTFD', 'is not set'),
+                 have_kconfig))]
           # At first, it disabled unprivileged userfaultfd,
           # and since v5.11 it enables unprivileged userfaultfd for user-mode only.
 
-    l += [SysctlCheck('cut_attack_surface', 'clipos', 'kernel.modules_disabled', '1')] # radical, but may be useful in some cases
+    l += [OR(SysctlCheck('cut_attack_surface', 'clipos', 'kernel.modules_disabled', '1'),
+             AND(KconfigCheck('cut_attack_surface', 'kspp', 'MODULES', 'is not set'),
+                 have_kconfig))] # radical, but may be useful in some cases
 
     l += [SysctlCheck('harden_userspace', 'kspp', 'fs.protected_symlinks', '1')]
     l += [SysctlCheck('harden_userspace', 'kspp', 'fs.protected_hardlinks', '1')]