Check the slab_nomerge cmdline parameter

[kconfig-hardened-check.git] / kconfig_hardened_check / __init__.py

diff --git a/kconfig_hardened_check/__init__.py b/kconfig_hardened_check/__init__.py
index 82aef99e2ffe0e363f6194871c368337d6644d44..fa06f8ecf169e388e931301bd47ad3c0fbab9dde 100644 (file)
--- a/kconfig_hardened_check/__init__.py
+++ b/kconfig_hardened_check/__init__.py
@@ -11,7 +11,6 @@
 #
 #
 # N.B Hardening command line parameters:
-#    slab_nomerge
 #    page_alloc.shuffle=1
 #    iommu=force (does it help against DMA attacks?)
 #    iommu.passthrough=0
@@ -21,7 +20,6 @@
 #    init_on_free=1 (since v5.3, otherwise slub_debug=P and page_poison=1)
 #    loadpin.enforce=1
 #    debugfs=no-mount (or off if possible)
-#    randomize_kstack_offset=1
 #
 #    Mitigations of CPU vulnerabilities:
 #       Аrch-independent:
@@ -39,6 +37,7 @@
 #           ssbd=force-on
 #
 #    Should NOT be set:
+#           slab_merge
 #           nokaslr
 #           rodata=off
 #           sysrq_always_enabled
@@ -85,7 +84,7 @@ import re
 import json
 from .__about__ import __version__
 
-TYPES_OF_CHECKS = ('kconfig', 'version')
+SIMPLE_OPTION_TYPES = ('kconfig', 'version', 'cmdline')
 
 class OptCheck:
     # Constructor without the 'expected' parameter is for option presence checks (any value is OK)
@@ -439,7 +438,8 @@ 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 += [stackleak_is_set]
-        l += [KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y')]
+        l += [OR(KconfigCheck('self_protection', 'kspp', 'RANDOMIZE_KSTACK_OFFSET_DEFAULT', 'y'),
+                 CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', '1'))]
     if arch in ('X86_64', 'X86_32'):
         l += [KconfigCheck('self_protection', 'kspp', 'SCHED_CORE', 'y')]
         l += [KconfigCheck('self_protection', 'kspp', 'DEFAULT_MMAP_MIN_ADDR', '65536')]
@@ -467,7 +467,8 @@ def add_kconfig_checks(l, arch):
     l += [KconfigCheck('self_protection', 'clipos', 'STATIC_USERMODEHELPER', 'y')] # needs userspace support
     l += [OR(KconfigCheck('self_protection', 'clipos', 'EFI_DISABLE_PCI_DMA', 'y'),
              efi_not_set)]
-    l += [KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set')] # slab_nomerge
+    l += [OR(KconfigCheck('self_protection', 'clipos', 'SLAB_MERGE_DEFAULT', 'is not set'),
+             CmdlineCheck('self_protection', 'kspp', 'slab_nomerge'))] # option presence check
     l += [KconfigCheck('self_protection', 'clipos', 'RANDOM_TRUST_BOOTLOADER', 'is not set')]
     l += [KconfigCheck('self_protection', 'clipos', 'RANDOM_TRUST_CPU', 'is not set')]
     l += [AND(KconfigCheck('self_protection', 'clipos', 'GCC_PLUGIN_RANDSTRUCT_PERFORMANCE', 'is not set'),
@@ -660,7 +661,6 @@ def add_cmdline_checks(l, arch):
     # Calling the CmdlineCheck class constructor:
     #     CmdlineCheck(reason, decision, name, expected)
 
-    l += [CmdlineCheck('self_protection', 'kspp', 'randomize_kstack_offset', 'on')]
     # TODO: add other
 
 
@@ -738,15 +738,15 @@ def print_checklist(mode, checklist, with_results):
 def populate_simple_opt_with_data(opt, data, data_type):
     if opt.type == 'complex':
         sys.exit('[!] ERROR: unexpected ComplexOptCheck {}: {}'.format(opt.name, vars(opt)))
-    if opt.type not in TYPES_OF_CHECKS:
+    if opt.type not in SIMPLE_OPTION_TYPES:
         sys.exit('[!] ERROR: invalid opt type "{}" for {}'.format(opt.type, opt.name))
-    if data_type not in TYPES_OF_CHECKS:
+    if data_type not in SIMPLE_OPTION_TYPES:
         sys.exit('[!] ERROR: invalid data type "{}"'.format(data_type))
 
     if data_type != opt.type:
         return
 
-    if data_type == 'kconfig':
+    if data_type in ('kconfig', 'cmdline'):
         opt.state = data.get(opt.name, None)
     elif data_type == 'version':
         opt.ver = data
@@ -763,7 +763,7 @@ def populate_opt_with_data(opt, data, data_type):
             else:
                 populate_simple_opt_with_data(o, data, data_type)
     else:
-        if opt.type != 'kconfig':
+        if opt.type not in ('kconfig', 'cmdline'):
             sys.exit('[!] ERROR: bad type "{}" for a simple check {}'.format(opt.type, opt.name))
         populate_simple_opt_with_data(opt, data, data_type)
 
@@ -802,6 +802,24 @@ def parse_kconfig_file(parsed_options, fname):
                 parsed_options[option] = value
 
 
+def parse_cmdline_file(parsed_options, fname):
+    with open(fname, 'r') as f:
+        line = f.readline()
+        opts = line.split()
+
+        line = f.readline()
+        if line:
+            sys.exit('[!] ERROR: more than one line in "{}"'.format(fname))
+
+        for opt in opts:
+            if '=' in opt:
+                name, value = opt.split('=', 1)
+            else:
+                name = opt
+                value = '' # '' is not None
+            parsed_options[name] = value
+
+
 def main():
     # Report modes:
     #   * verbose mode for
@@ -858,6 +876,15 @@ def main():
         populate_with_data(config_checklist, parsed_kconfig_options, 'kconfig')
         populate_with_data(config_checklist, kernel_version, 'version')
 
+        if args.cmdline:
+            # add relevant cmdline checks to the checklist
+            add_cmdline_checks(config_checklist, arch)
+
+            # populate the checklist with the parsed kconfig data
+            parsed_cmdline_options = OrderedDict()
+            parse_cmdline_file(parsed_cmdline_options, args.cmdline)
+            populate_with_data(config_checklist, parsed_cmdline_options, 'cmdline')
+
         # now everything is ready for performing the checks
         perform_checks(config_checklist)