From: Alexander Popov Date: Tue, 14 Jan 2020 10:28:25 +0000 (+0300) Subject: Fix INIT_ON_FREE_DEFAULT_ON vs PAGE_POISONING issue #28 X-Git-Tag: v0.5.5~46 X-Git-Url: https://jxself.org/git/?a=commitdiff_plain;h=991fb61eec374576f5f886c6a53f6e0a5adbc8ee;p=kconfig-hardened-check.git Fix INIT_ON_FREE_DEFAULT_ON vs PAGE_POISONING issue #28 PAGE_POISONING is a debugging feature. It provides less erasing than INIT_ON_FREE_DEFAULT_ON. Join these checks with OR giving preference to INIT_ON_FREE_DEFAULT_ON. Thanks to @madaidan for the details. Also drop my previous recommendations about CONFIG_PAGE_POISONING_NO_SANITY and CONFIG_PAGE_POISONING_ZERO. --- diff --git a/README.md b/README.md index 5801b69..0c9aaec 100644 --- a/README.md +++ b/README.md @@ -86,7 +86,6 @@ CONFIG_DEBUG_LIST | y | kspp | self_pr CONFIG_DEBUG_SG | y | kspp | self_protection | FAIL: "is not set" CONFIG_DEBUG_CREDENTIALS | y | kspp | self_protection | FAIL: "is not set" CONFIG_DEBUG_NOTIFIERS | y | kspp | self_protection | FAIL: "is not set" -CONFIG_PAGE_POISONING | y | kspp | self_protection | FAIL: "is not set" CONFIG_HARDENED_USERCOPY | y | kspp | self_protection | OK CONFIG_HARDENED_USERCOPY_FALLBACK | is not set | kspp | self_protection | OK: not found CONFIG_MODULE_SIG | y | kspp | self_protection | OK @@ -111,8 +110,6 @@ CONFIG_INTEL_IOMMU_SVM | y | clipos | self_pr CONFIG_INTEL_IOMMU_DEFAULT_ON | y | clipos | self_protection | FAIL: "is not set" CONFIG_SLUB_DEBUG_ON | y | my | self_protection | FAIL: "is not set" CONFIG_RESET_ATTACK_MITIGATION | y | my | self_protection | OK -CONFIG_PAGE_POISONING_NO_SANITY | is not set | my | self_protection | FAIL: CONFIG_PAGE_POISONING is needed -CONFIG_PAGE_POISONING_ZERO | is not set | my | self_protection | FAIL: CONFIG_PAGE_POISONING is needed CONFIG_AMD_IOMMU_V2 | y | my | self_protection | FAIL: "m" CONFIG_SECURITY | y |defconfig | security_policy | OK CONFIG_SECURITY_WRITABLE_HOOKS | is not set |defconfig | security_policy | OK @@ -181,7 +178,7 @@ CONFIG_BPF_JIT | is not set | my | cut_atta CONFIG_VIDEO_VIVID | is not set | my | cut_attack_surface | FAIL: "m" CONFIG_ARCH_MMAP_RND_BITS | 32 | clipos |userspace_hardening | FAIL: "28" -[+] config check is finished: 'OK' - 49 / 'FAIL' - 77 +[+] config check is finished: 'OK' - 49 / 'FAIL' - 74 ``` ## kconfig-hardened-check versioning diff --git a/kconfig-hardened-check.py b/kconfig-hardened-check.py index d5215b1..86e0d01 100755 --- a/kconfig-hardened-check.py +++ b/kconfig-hardened-check.py @@ -11,13 +11,13 @@ # # # N.B Hardening command line parameters: -# page_poison=1 # slub_debug=FZP # slab_nomerge # kernel.kptr_restrict=1 # lockdown=1 (is it changed?) # page_alloc.shuffle=1 # iommu=force (does it help against DMA attacks?) +# page_poison=1 (if enabled) # # Mitigations of CPU vulnerabilities: # Аrch-independent: @@ -233,8 +233,6 @@ def construct_checklist(checklist, arch): checklist.append(OptCheck('DEBUG_SG', 'y', 'kspp', 'self_protection')) checklist.append(OptCheck('DEBUG_CREDENTIALS', 'y', 'kspp', 'self_protection')) checklist.append(OptCheck('DEBUG_NOTIFIERS', 'y', 'kspp', 'self_protection')) - page_poisoning_is_set = OptCheck('PAGE_POISONING', 'y', 'kspp', 'self_protection') - checklist.append(page_poisoning_is_set) hardened_usercopy_is_set = OptCheck('HARDENED_USERCOPY', 'y', 'kspp', 'self_protection') checklist.append(hardened_usercopy_is_set) checklist.append(AND(OptCheck('HARDENED_USERCOPY_FALLBACK', 'is not set', 'kspp', 'self_protection'), \ @@ -262,7 +260,8 @@ def construct_checklist(checklist, arch): checklist.append(OR(OptCheck('INIT_STACK_ALL', 'y', 'clipos', 'self_protection'), \ OptCheck('GCC_PLUGIN_STRUCTLEAK_BYREF_ALL', 'y', 'kspp', 'self_protection'))) checklist.append(OptCheck('INIT_ON_ALLOC_DEFAULT_ON', 'y', 'clipos', 'self_protection')) - checklist.append(OptCheck('INIT_ON_FREE_DEFAULT_ON', 'y', 'clipos', 'self_protection')) + checklist.append(OR(OptCheck('INIT_ON_FREE_DEFAULT_ON', 'y', 'clipos', 'self_protection'), \ + OptCheck('PAGE_POISONING', 'y', 'kspp', 'self_protection'))) checklist.append(OptCheck('SECURITY_DMESG_RESTRICT', 'y', 'clipos', 'self_protection')) checklist.append(OptCheck('DEBUG_VIRTUAL', 'y', 'clipos', 'self_protection')) checklist.append(OptCheck('STATIC_USERMODEHELPER', 'y', 'clipos', 'self_protection')) # needs userspace support (systemd) @@ -285,10 +284,6 @@ def construct_checklist(checklist, arch): checklist.append(OptCheck('SLUB_DEBUG_ON', 'y', 'my', 'self_protection')) checklist.append(OptCheck('RESET_ATTACK_MITIGATION', 'y', 'my', 'self_protection')) # needs userspace support (systemd) - checklist.append(AND(OptCheck('PAGE_POISONING_NO_SANITY', 'is not set', 'my', 'self_protection'), \ - page_poisoning_is_set)) - checklist.append(AND(OptCheck('PAGE_POISONING_ZERO', 'is not set', 'my', 'self_protection'), \ - page_poisoning_is_set)) if debug_mode or arch == 'X86_64': checklist.append(AND(OptCheck('AMD_IOMMU_V2', 'y', 'my', 'self_protection'), \ iommu_support_is_set))