The user-mode indirect branch tracking support is done mostly by GCC to insert ENDBR64/ENDBR32 instructions at branch targets. The kernel provides CPUID enumeration and feature setup. Signed-off-by: Yu-cheng Yu <yu-cheng.yu@xxxxxxxxx> --- arch/x86/Kconfig | 16 ++++++++++++++++ arch/x86/Makefile | 7 +++++++ 2 files changed, 23 insertions(+) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index df8b57de75b2..47afe47c01eb 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1921,6 +1921,9 @@ config X86_INTEL_CET config ARCH_HAS_SHSTK def_bool n +config ARCH_HAS_AS_LIMIT + def_bool n + config X86_INTEL_SHADOW_STACK_USER prompt "Intel Shadow Stack for user-mode" def_bool n @@ -1941,6 +1944,19 @@ config X86_INTEL_SHADOW_STACK_USER If unsure, say y. +config X86_INTEL_BRANCH_TRACKING_USER + prompt "Intel Indirect Branch Tracking for user-mode" + def_bool n + depends on CPU_SUP_INTEL && X86_64 + select X86_INTEL_CET + select ARCH_HAS_AS_LIMIT + select ARCH_USE_GNU_PROPERTY + ---help--- + Indirect Branch Tracking provides hardware protection against return-/jmp- + oriented programming attacks. + + If unsure, say y + config EFI bool "EFI runtime service support" depends on ACPI diff --git a/arch/x86/Makefile b/arch/x86/Makefile index 0b2e9df48907..25372cc4a303 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -155,6 +155,13 @@ ifdef CONFIG_X86_INTEL_SHADOW_STACK_USER endif endif +# Check compiler ibt support +ifdef CONFIG_X86_INTEL_BRANCH_TRACKING_USER + ifeq ($(call cc-option-yn, -fcf-protection=branch), n) + $(error CONFIG_X86_INTEL_BRANCH_TRACKING_USER not supported by compiler) + endif +endif + # # If the function graph tracer is used with mcount instead of fentry, # '-maccumulate-outgoing-args' is needed to prevent a GCC bug -- 2.17.1
