Control-flow Enforcement (CET) is a new Intel processor feature that blocks return/jump-oriented programming attacks. Details can be found in "Intel 64 and IA-32 Architectures Software Developer's Manual" [1]. This series depends on the XSAVES supervisor state series that was split out and submitted earlier [2]. Changes from v8: - Simplify signal handling code. - Add guard pages around a Shadow Stack. - Replace ELF parser with Dave Martin's patch [3]. The goal of this posting is to seek additional comments. [1] Intel 64 and IA-32 Architectures Software Developer's Manual: https://software.intel.com/en-us/download/intel-64-and-ia-32- architectures-sdm-combined-volumes-1-2a-2b-2c-2d-3a-3b-3c-3d-and-4 [2] XSAVES supervisor states patches: https://lkml.kernel.org/r/20200121201843.12047-1-yu-cheng.yu@xxxxxxxxx/ [3] Dave Martin's ELF program property parsing patch: https://lkml.kernel.org/r/20200122212144.6409-3-broonie@xxxxxxxxxx/ [4] CET patches v8: https://lkml.kernel.org/r/20190813205225.12032-1-yu-cheng.yu@xxxxxxxxx/ https://lkml.kernel.org/r/20190813205359.12196-1-yu-cheng.yu@xxxxxxxxx/ Dave Martin (1): ELF: Add ELF program property parsing support Yu-cheng Yu (26): Documentation/x86: Add CET description x86/cpufeatures: Add CET CPU feature flags for Control-flow Enforcement Technology (CET) x86/fpu/xstate: Introduce CET MSR XSAVES supervisor states x86/cet: Add control-protection fault handler x86/cet/shstk: Add Kconfig option for user-mode Shadow Stack protection mm: Introduce VM_SHSTK for Shadow Stack memory Add guard pages around a Shadow Stack. x86/mm: Change _PAGE_DIRTY to _PAGE_DIRTY_HW x86/mm: Introduce _PAGE_DIRTY_SW x86/mm: Update pte_modify, pmd_modify, and _PAGE_CHG_MASK for _PAGE_DIRTY_SW drm/i915/gvt: Change _PAGE_DIRTY to _PAGE_DIRTY_BITS x86/mm: Modify ptep_set_wrprotect and pmdp_set_wrprotect for _PAGE_DIRTY_SW x86/mm: Shadow Stack page fault error checking mm: Handle Shadow Stack page fault mm: Handle THP/HugeTLB Shadow Stack page fault mm: Update can_follow_write_pte() for Shadow Stack x86/cet/shstk: User-mode Shadow Stack support x86/cet/shstk: Introduce WRUSS instruction x86/cet/shstk: Handle signals for Shadow Stack ELF: UAPI and Kconfig additions for ELF program properties binfmt_elf: Define GNU_PROPERTY_X86_FEATURE_1_AND ELF: Introduce arch_setup_elf_property() x86/cet/shstk: ELF header parsing for Shadow Stack x86/cet/shstk: Handle thread Shadow Stack mm/mmap: Add Shadow Stack pages to memory accounting x86/cet/shstk: Add arch_prctl functions for Shadow Stack .../admin-guide/kernel-parameters.txt | 6 + Documentation/x86/index.rst | 1 + Documentation/x86/intel_cet.rst | 294 +++++++++++++++ arch/x86/Kconfig | 24 ++ arch/x86/Makefile | 7 + arch/x86/entry/entry_64.S | 2 +- arch/x86/ia32/ia32_signal.c | 17 + arch/x86/include/asm/cet.h | 44 +++ arch/x86/include/asm/cpufeatures.h | 2 + arch/x86/include/asm/disabled-features.h | 8 +- arch/x86/include/asm/elf.h | 13 + arch/x86/include/asm/fpu/internal.h | 2 + arch/x86/include/asm/fpu/types.h | 22 ++ arch/x86/include/asm/fpu/xstate.h | 5 +- arch/x86/include/asm/mmu_context.h | 3 + arch/x86/include/asm/msr-index.h | 18 + arch/x86/include/asm/pgtable.h | 197 +++++++++- arch/x86/include/asm/pgtable_types.h | 50 ++- arch/x86/include/asm/processor.h | 5 + arch/x86/include/asm/special_insns.h | 32 ++ arch/x86/include/asm/traps.h | 5 + arch/x86/include/uapi/asm/prctl.h | 5 + arch/x86/include/uapi/asm/processor-flags.h | 2 + arch/x86/include/uapi/asm/sigcontext.h | 9 + arch/x86/kernel/Makefile | 2 + arch/x86/kernel/cet.c | 344 ++++++++++++++++++ arch/x86/kernel/cet_prctl.c | 84 +++++ arch/x86/kernel/cpu/common.c | 25 ++ arch/x86/kernel/cpu/cpuid-deps.c | 2 + arch/x86/kernel/fpu/signal.c | 89 +++++ arch/x86/kernel/fpu/xstate.c | 25 +- arch/x86/kernel/idt.c | 4 + arch/x86/kernel/process.c | 12 +- arch/x86/kernel/process_64.c | 31 ++ arch/x86/kernel/relocate_kernel_64.S | 2 +- arch/x86/kernel/signal.c | 10 + arch/x86/kernel/signal_compat.c | 2 +- arch/x86/kernel/traps.c | 59 +++ arch/x86/kvm/vmx/vmx.c | 2 +- arch/x86/mm/fault.c | 18 + arch/x86/mm/mmap.c | 2 + arch/x86/mm/pgtable.c | 41 +++ drivers/gpu/drm/i915/gvt/gtt.c | 2 +- fs/Kconfig.binfmt | 3 + fs/binfmt_elf.c | 131 +++++++ fs/compat_binfmt_elf.c | 4 + fs/proc/task_mmu.c | 3 + include/asm-generic/pgtable.h | 40 ++ include/linux/elf.h | 33 ++ include/linux/mm.h | 28 +- include/uapi/asm-generic/siginfo.h | 3 +- include/uapi/linux/elf.h | 12 + mm/gup.c | 8 +- mm/huge_memory.c | 12 +- mm/memory.c | 7 +- mm/mmap.c | 5 + .../arch/x86/include/asm/disabled-features.h | 8 +- 57 files changed, 1779 insertions(+), 47 deletions(-) create mode 100644 Documentation/x86/intel_cet.rst create mode 100644 arch/x86/include/asm/cet.h create mode 100644 arch/x86/kernel/cet.c create mode 100644 arch/x86/kernel/cet_prctl.c -- 2.21.0