From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yu-cheng Yu Subject: [RFC PATCH v9 4/7] x86/cet/ibt: ELF header parsing for Indirect Branch Tracking Date: Wed, 5 Feb 2020 10:23:05 -0800 Message-ID: <20200205182308.4028-5-yu-cheng.yu@intel.com> References: <20200205182308.4028-1-yu-cheng.yu@intel.com> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20200205182308.4028-1-yu-cheng.yu@intel.com> Sender: linux-kernel-owner@vger.kernel.org To: x86@kernel.org, "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-api@vger.kernel.org, Arnd Bergmann , Andy Lutomirski , Balbir Singh , Borislav Petkov , Cyrill Gorcunov , Dave Hansen , Eugene Syromiatnikov , Florian Weimer , "H.J. Lu" , Jann Horn , Jonathan Corbet , Kees Cook , Mike Kravetz , Nadav Amit Cc: Yu-cheng Yu List-Id: linux-api@vger.kernel.org Update arch_setup_elf_property() for Indirect Branch Tracking. v9: - Change cpu_feature_enabled() to static_cpu_has(). Signed-off-by: Yu-cheng Yu --- arch/x86/Kconfig | 2 ++ arch/x86/kernel/process_64.c | 5 +++++ 2 files changed, 7 insertions(+) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 563f3c81f323..5c260c047e3c 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2003,6 +2003,8 @@ config X86_INTEL_BRANCH_TRACKING_USER def_bool n depends on CPU_SUP_INTEL && X86_64 select X86_INTEL_CET + select ARCH_USE_GNU_PROPERTY + select ARCH_BINFMT_ELF_STATE ---help--- Indirect Branch Tracking (IBT) provides protection against CALL-/JMP-oriented programming attacks. It is active when diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index 99548cde0cc6..9f81b413d975 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -760,6 +760,11 @@ int arch_setup_elf_property(struct arch_elf_state *state) return r; } + if (static_cpu_has(X86_FEATURE_IBT)) { + if (state->gnu_property & GNU_PROPERTY_X86_FEATURE_1_IBT) + r = cet_setup_ibt(); + } + return r; } #endif -- 2.21.0