From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yu-cheng Yu Subject: [PATCH v8 05/14] x86/cet/ibt: ELF header parsing for IBT Date: Tue, 13 Aug 2019 13:53:50 -0700 Message-ID: <20190813205359.12196-6-yu-cheng.yu@intel.com> References: <20190813205359.12196-1-yu-cheng.yu@intel.com> Return-path: In-Reply-To: <20190813205359.12196-1-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 Look in .note.gnu.property of an ELF file and check if Indirect Branch Tracking needs to be enabled for the task. Signed-off-by: Yu-cheng Yu --- arch/x86/Kconfig | 1 + arch/x86/kernel/process_64.c | 5 +++++ 2 files changed, 6 insertions(+) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 666dc66a382e..7edb544cef00 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1971,6 +1971,7 @@ config X86_INTEL_BRANCH_TRACKING_USER select X86_INTEL_CET select ARCH_HAS_AS_LIMIT select ARCH_USE_GNU_PROPERTY + select ARCH_BINFMT_ELF_STATE ---help--- Indirect Branch Tracking provides hardware protection against return-/jmp- oriented programming attacks. diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index 7ec60b14e96d..a051cfc5242f 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -856,6 +856,11 @@ int arch_setup_property(struct arch_elf_state *state) return r; } + if (cpu_feature_enabled(X86_FEATURE_IBT)) { + if (state->gnu_property & GNU_PROPERTY_X86_FEATURE_1_IBT) + r = cet_setup_ibt(); + } + return r; } #endif -- 2.17.1