From patchwork Mon Aug 30 18:22:12 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yu-cheng Yu X-Patchwork-Id: 12465777 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 45D78C432BE for ; Mon, 30 Aug 2021 18:23:14 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id EDD0E60FED for ; Mon, 30 Aug 2021 18:23:13 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org EDD0E60FED Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id EAEB06B0075; Mon, 30 Aug 2021 14:23:12 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E85AC8D0001; Mon, 30 Aug 2021 14:23:12 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D73F26B007E; Mon, 30 Aug 2021 14:23:12 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0095.hostedemail.com [216.40.44.95]) by kanga.kvack.org (Postfix) with ESMTP id C9DF06B0075 for ; Mon, 30 Aug 2021 14:23:12 -0400 (EDT) Received: from smtpin26.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 88FBA274A1 for ; Mon, 30 Aug 2021 18:23:12 +0000 (UTC) X-FDA: 78532569024.26.3CE67E7 Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by imf03.hostedemail.com (Postfix) with ESMTP id E5F8030000A9 for ; Mon, 30 Aug 2021 18:23:11 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10092"; a="282043645" X-IronPort-AV: E=Sophos;i="5.84,364,1620716400"; d="scan'208";a="282043645" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Aug 2021 11:23:09 -0700 X-IronPort-AV: E=Sophos;i="5.84,364,1620716400"; d="scan'208";a="540650943" Received: from yyu32-desk.sc.intel.com ([143.183.136.146]) by fmsmga002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Aug 2021 11:23:08 -0700 From: Yu-cheng Yu 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 , Oleg Nesterov , Pavel Machek , Peter Zijlstra , Randy Dunlap , "Ravi V. Shankar" , Dave Martin , Weijiang Yang , Pengfei Xu , Haitao Huang , Rick P Edgecombe Cc: Yu-cheng Yu Subject: [PATCH v30 01/10] x86/cet/ibt: Add Kconfig option for Indirect Branch Tracking Date: Mon, 30 Aug 2021 11:22:12 -0700 Message-Id: <20210830182221.3535-2-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20210830182221.3535-1-yu-cheng.yu@intel.com> References: <20210830182221.3535-1-yu-cheng.yu@intel.com> MIME-Version: 1.0 Authentication-Results: imf03.hostedemail.com; dkim=none; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=intel.com (policy=none); spf=none (imf03.hostedemail.com: domain of yu-cheng.yu@intel.com has no SPF policy when checking 134.134.136.100) smtp.mailfrom=yu-cheng.yu@intel.com X-Stat-Signature: z57atggd6cr6bcwwbx5d3acuwbzy4irc X-Rspamd-Queue-Id: E5F8030000A9 X-Rspamd-Server: rspam04 X-HE-Tag: 1630347791-444310 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Indirect Branch Tracking (IBT) provides protection against CALL-/JMP- oriented programming attacks. It is active when the kernel has this feature enabled, and the processor and the application support it. When this feature is enabled, legacy non-IBT applications continue to work, but without IBT protection. Signed-off-by: Yu-cheng Yu Reviewed-by: Kees Cook --- arch/x86/Kconfig | 19 +++++++++++++++++++ arch/x86/include/asm/disabled-features.h | 8 +++++++- 2 files changed, 26 insertions(+), 1 deletion(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 34692f02118c..b063d6d2491f 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1932,6 +1932,25 @@ config X86_SHADOW_STACK If unsure, say N. +config X86_IBT + prompt "Intel Indirect Branch Tracking" + def_bool n + depends on X86_SHADOW_STACK + depends on $(cc-option,-fcf-protection) + help + Indirect Branch Tracking (IBT) provides protection against + CALL-/JMP-oriented programming attacks. It is active when + the kernel has this feature enabled, and the processor and + the application support it. When this feature is enabled, + legacy non-IBT applications continue to work, but without + IBT protection. + Support for this feature is present on Tiger Lake family of + processors released in 2020 or later. Enabling this feature + increases kernel text size by 3.7 KB. + See Documentation/x86/intel_cet.rst for more information. + + If unsure, say N. + config EFI bool "EFI runtime service support" depends on ACPI diff --git a/arch/x86/include/asm/disabled-features.h b/arch/x86/include/asm/disabled-features.h index b7728f7afb2b..e3a08fcd72f4 100644 --- a/arch/x86/include/asm/disabled-features.h +++ b/arch/x86/include/asm/disabled-features.h @@ -71,6 +71,12 @@ #define DISABLE_SHSTK (1 << (X86_FEATURE_SHSTK & 31)) #endif +#ifdef CONFIG_X86_IBT +#define DISABLE_IBT 0 +#else +#define DISABLE_IBT (1 << (X86_FEATURE_IBT & 31)) +#endif + /* * Make sure to add features to the correct mask */ @@ -93,7 +99,7 @@ #define DISABLED_MASK16 (DISABLE_PKU|DISABLE_OSPKE|DISABLE_LA57|DISABLE_UMIP| \ DISABLE_ENQCMD|DISABLE_SHSTK) #define DISABLED_MASK17 0 -#define DISABLED_MASK18 0 +#define DISABLED_MASK18 (DISABLE_IBT) #define DISABLED_MASK19 0 #define DISABLED_MASK_CHECK BUILD_BUG_ON_ZERO(NCAPINTS != 20) From patchwork Mon Aug 30 18:22:13 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yu-cheng Yu X-Patchwork-Id: 12465779 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 64CFDC4320A for ; Mon, 30 Aug 2021 18:23:16 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 16CCC60FD9 for ; Mon, 30 Aug 2021 18:23:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 16CCC60FD9 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 428426B007B; Mon, 30 Aug 2021 14:23:13 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 3D7C36B007E; Mon, 30 Aug 2021 14:23:13 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 252A46B0080; Mon, 30 Aug 2021 14:23:13 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0018.hostedemail.com [216.40.44.18]) by kanga.kvack.org (Postfix) with ESMTP id 16E7C6B007B for ; Mon, 30 Aug 2021 14:23:13 -0400 (EDT) Received: from smtpin06.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id D0259181AF5C1 for ; Mon, 30 Aug 2021 18:23:12 +0000 (UTC) X-FDA: 78532569024.06.BE1EDA0 Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by imf11.hostedemail.com (Postfix) with ESMTP id 4B1DDF0000A1 for ; Mon, 30 Aug 2021 18:23:12 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10092"; a="282043649" X-IronPort-AV: E=Sophos;i="5.84,364,1620716400"; d="scan'208";a="282043649" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Aug 2021 11:23:09 -0700 X-IronPort-AV: E=Sophos;i="5.84,364,1620716400"; d="scan'208";a="540650946" Received: from yyu32-desk.sc.intel.com ([143.183.136.146]) by fmsmga002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Aug 2021 11:23:09 -0700 From: Yu-cheng Yu 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 , Oleg Nesterov , Pavel Machek , Peter Zijlstra , Randy Dunlap , "Ravi V. Shankar" , Dave Martin , Weijiang Yang , Pengfei Xu , Haitao Huang , Rick P Edgecombe Cc: Yu-cheng Yu Subject: [PATCH v30 02/10] x86/cet/ibt: Add user-mode Indirect Branch Tracking support Date: Mon, 30 Aug 2021 11:22:13 -0700 Message-Id: <20210830182221.3535-3-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20210830182221.3535-1-yu-cheng.yu@intel.com> References: <20210830182221.3535-1-yu-cheng.yu@intel.com> MIME-Version: 1.0 Authentication-Results: imf11.hostedemail.com; dkim=none; spf=none (imf11.hostedemail.com: domain of yu-cheng.yu@intel.com has no SPF policy when checking 134.134.136.100) smtp.mailfrom=yu-cheng.yu@intel.com; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=intel.com (policy=none) X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 4B1DDF0000A1 X-Stat-Signature: f4r6t6kjmscu3oeaj3kkohph7fd1k7pq X-HE-Tag: 1630347792-181710 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Introduce user-mode Indirect Branch Tracking (IBT) support. Add routines for the setup/disable of IBT. Signed-off-by: Yu-cheng Yu Cc: Kees Cook --- v28: - When IBT feature is not present, make ibt_setup() return success, since this is a setup function. v27: - Change struct thread_shstk: ibt_enabled to ibt. - Create a helper for set/clear bits of MSR_IA32_U_CET. --- arch/x86/include/asm/cet.h | 9 ++++++ arch/x86/kernel/Makefile | 1 + arch/x86/kernel/ibt.c | 58 ++++++++++++++++++++++++++++++++++++++ 3 files changed, 68 insertions(+) create mode 100644 arch/x86/kernel/ibt.c diff --git a/arch/x86/include/asm/cet.h b/arch/x86/include/asm/cet.h index fb32cb093ebb..bc04b2d3487d 100644 --- a/arch/x86/include/asm/cet.h +++ b/arch/x86/include/asm/cet.h @@ -11,6 +11,7 @@ struct thread_shstk { u64 base; u64 size; u64 locked:1; + u64 ibt:1; }; #ifdef CONFIG_X86_SHADOW_STACK @@ -39,6 +40,14 @@ static inline int setup_signal_shadow_stack(int proc32, void __user *restorer) { static inline int restore_signal_shadow_stack(void) { return 0; } #endif +#ifdef CONFIG_X86_IBT +int ibt_setup(void); +void ibt_disable(void); +#else +static inline int ibt_setup(void) { return 0; } +static inline void ibt_disable(void) {} +#endif + #ifdef CONFIG_X86_SHADOW_STACK int prctl_cet(int option, u64 arg2); #else diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index 39e826b5cabd..cce07a920fec 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -152,6 +152,7 @@ obj-$(CONFIG_UNWINDER_GUESS) += unwind_guess.o obj-$(CONFIG_AMD_MEM_ENCRYPT) += sev.o obj-$(CONFIG_X86_SHADOW_STACK) += shstk.o obj-$(CONFIG_X86_SHADOW_STACK) += shstk.o cet_prctl.o +obj-$(CONFIG_X86_IBT) += ibt.o ### # 64 bit specific files ifeq ($(CONFIG_X86_64),y) diff --git a/arch/x86/kernel/ibt.c b/arch/x86/kernel/ibt.c new file mode 100644 index 000000000000..4ab7af33b274 --- /dev/null +++ b/arch/x86/kernel/ibt.c @@ -0,0 +1,58 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * ibt.c - Intel Indirect Branch Tracking support + * + * Copyright (c) 2021, Intel Corporation. + * Yu-cheng Yu + */ + +#include +#include +#include +#include +#include +#include + +static int ibt_set_clear_msr_bits(u64 set, u64 clear) +{ + u64 msr; + int r; + + fpregs_lock(); + + if (test_thread_flag(TIF_NEED_FPU_LOAD)) + fpregs_restore_userregs(); + + r = rdmsrl_safe(MSR_IA32_U_CET, &msr); + if (!r) { + msr = (msr & ~clear) | set; + r = wrmsrl_safe(MSR_IA32_U_CET, msr); + } + + fpregs_unlock(); + + return r; +} + +int ibt_setup(void) +{ + int r; + + if (!cpu_feature_enabled(X86_FEATURE_IBT)) + return 0; + + r = ibt_set_clear_msr_bits(CET_ENDBR_EN | CET_NO_TRACK_EN, 0); + if (!r) + current->thread.shstk.ibt = 1; + + return r; +} + +void ibt_disable(void) +{ + if (!current->thread.shstk.ibt) + return; + + ibt_set_clear_msr_bits(0, CET_ENDBR_EN); + current->thread.shstk.ibt = 0; +} From patchwork Mon Aug 30 18:22:14 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yu-cheng Yu X-Patchwork-Id: 12465781 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8577DC432BE for ; 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Mon, 30 Aug 2021 18:23:13 +0000 (UTC) X-FDA: 78532569066.16.7FE4A2C Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by imf03.hostedemail.com (Postfix) with ESMTP id A798A300009B for ; Mon, 30 Aug 2021 18:23:12 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10092"; a="282043655" X-IronPort-AV: E=Sophos;i="5.84,364,1620716400"; d="scan'208";a="282043655" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Aug 2021 11:23:09 -0700 X-IronPort-AV: E=Sophos;i="5.84,364,1620716400"; d="scan'208";a="540650949" Received: from yyu32-desk.sc.intel.com ([143.183.136.146]) by fmsmga002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Aug 2021 11:23:09 -0700 From: Yu-cheng Yu 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 , Oleg Nesterov , Pavel Machek , Peter Zijlstra , Randy Dunlap , "Ravi V. Shankar" , Dave Martin , Weijiang Yang , Pengfei Xu , Haitao Huang , Rick P Edgecombe Cc: Yu-cheng Yu Subject: [PATCH v30 03/10] x86/cet/ibt: Handle signals for Indirect Branch Tracking Date: Mon, 30 Aug 2021 11:22:14 -0700 Message-Id: <20210830182221.3535-4-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20210830182221.3535-1-yu-cheng.yu@intel.com> References: <20210830182221.3535-1-yu-cheng.yu@intel.com> MIME-Version: 1.0 Authentication-Results: imf03.hostedemail.com; dkim=none; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=intel.com (policy=none); spf=none (imf03.hostedemail.com: domain of yu-cheng.yu@intel.com has no SPF policy when checking 134.134.136.100) smtp.mailfrom=yu-cheng.yu@intel.com X-Stat-Signature: n8799s6i398y6ff8ndt3g7cuygdm1zkw X-Rspamd-Queue-Id: A798A300009B X-Rspamd-Server: rspam04 X-HE-Tag: 1630347792-802407 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: IBT state machine tracks CALL/JMP instructions. When a such instruction is executed and before arriving at an ENDBR, it is in WAIT_FOR_ENDBR state, which can be read from CET_WAIT_ENDBR bit of MSR_IA32_U_CET. Further details are described in Intel SDM Vol. 1, Sec. 18.3. In handling signals, WAIT_FOR_ENDBR state is saved/restored with a new UC_WAIT_ENDBR flag being introduced. A legacy IA32 signal frame does not have ucontext, and cannot be supported with a uc flag. Thus, IBT feature is not supported for ia32 app's, which is handled in a separate patch. Signed-off-by: Yu-cheng Yu Cc: Andy Lutomirski Cc: Cyrill Gorcunov Cc: Florian Weimer Cc: H. Peter Anvin Cc: Kees Cook Link: https://lore.kernel.org/linux-api/f6e61dae-9805-c855-8873-7481ceb7ea79@intel.com/ --- arch/x86/ia32/ia32_signal.c | 15 ++++++++-- arch/x86/include/asm/cet.h | 4 +++ arch/x86/include/uapi/asm/ucontext.h | 5 ++++ arch/x86/kernel/ibt.c | 41 ++++++++++++++++++++++++++++ arch/x86/kernel/signal.c | 6 ++++ 5 files changed, 68 insertions(+), 3 deletions(-) diff --git a/arch/x86/ia32/ia32_signal.c b/arch/x86/ia32/ia32_signal.c index d7a30bc98e66..77d0fa90cc19 100644 --- a/arch/x86/ia32/ia32_signal.c +++ b/arch/x86/ia32/ia32_signal.c @@ -129,6 +129,7 @@ COMPAT_SYSCALL_DEFINE0(rt_sigreturn) { struct pt_regs *regs = current_pt_regs(); struct rt_sigframe_ia32 __user *frame; + unsigned int uc_flags; sigset_t set; frame = (struct rt_sigframe_ia32 __user *)(regs->sp - 4); @@ -137,6 +138,11 @@ COMPAT_SYSCALL_DEFINE0(rt_sigreturn) goto badframe; if (__get_user(set.sig[0], (__u64 __user *)&frame->uc.uc_sigmask)) goto badframe; + if (__get_user(uc_flags, &frame->uc.uc_flags)) + goto badframe; + + if (uc_flags & UC_WAIT_ENDBR) + ibt_set_wait_endbr(); set_current_blocked(&set); @@ -312,6 +318,7 @@ int ia32_setup_rt_frame(int sig, struct ksignal *ksig, compat_sigset_t *set, struct pt_regs *regs) { struct rt_sigframe_ia32 __user *frame; + unsigned int uc_flags = 0; void __user *restorer; void __user *fp = NULL; @@ -339,6 +346,9 @@ int ia32_setup_rt_frame(int sig, struct ksignal *ksig, if (setup_signal_shadow_stack(1, restorer)) return -EFAULT; + if (ibt_get_clear_wait_endbr()) + uc_flags |= UC_WAIT_ENDBR; + if (!user_access_begin(frame, sizeof(*frame))) return -EFAULT; @@ -348,9 +358,8 @@ int ia32_setup_rt_frame(int sig, struct ksignal *ksig, /* Create the ucontext. */ if (static_cpu_has(X86_FEATURE_XSAVE)) - unsafe_put_user(UC_FP_XSTATE, &frame->uc.uc_flags, Efault); - else - unsafe_put_user(0, &frame->uc.uc_flags, Efault); + uc_flags |= UC_FP_XSTATE; + unsafe_put_user(uc_flags, &frame->uc.uc_flags, Efault); unsafe_put_user(0, &frame->uc.uc_link, Efault); unsafe_compat_save_altstack(&frame->uc.uc_stack, regs->sp, Efault); diff --git a/arch/x86/include/asm/cet.h b/arch/x86/include/asm/cet.h index bc04b2d3487d..152c717c9cdb 100644 --- a/arch/x86/include/asm/cet.h +++ b/arch/x86/include/asm/cet.h @@ -43,9 +43,13 @@ static inline int restore_signal_shadow_stack(void) { return 0; } #ifdef CONFIG_X86_IBT int ibt_setup(void); void ibt_disable(void); +int ibt_get_clear_wait_endbr(void); +int ibt_set_wait_endbr(void); #else static inline int ibt_setup(void) { return 0; } static inline void ibt_disable(void) {} +static inline int ibt_get_clear_wait_endbr(void) { return 0; } +static inline int ibt_set_wait_endbr(void) { return 0; } #endif #ifdef CONFIG_X86_SHADOW_STACK diff --git a/arch/x86/include/uapi/asm/ucontext.h b/arch/x86/include/uapi/asm/ucontext.h index 5657b7a49f03..905419de2cc7 100644 --- a/arch/x86/include/uapi/asm/ucontext.h +++ b/arch/x86/include/uapi/asm/ucontext.h @@ -51,6 +51,11 @@ #define UC_STRICT_RESTORE_SS 0x4 #endif +/* + * Indicates IBT WAIT-ENDBR status. + */ +#define UC_WAIT_ENDBR 0x08 + #include #endif /* _ASM_X86_UCONTEXT_H */ diff --git a/arch/x86/kernel/ibt.c b/arch/x86/kernel/ibt.c index 4ab7af33b274..5ab8632a1f7e 100644 --- a/arch/x86/kernel/ibt.c +++ b/arch/x86/kernel/ibt.c @@ -56,3 +56,44 @@ void ibt_disable(void) ibt_set_clear_msr_bits(0, CET_ENDBR_EN); current->thread.shstk.ibt = 0; } + +int ibt_get_clear_wait_endbr(void) +{ + u64 msr_val = 0; + + if (!current->thread.shstk.ibt) + return 0; + + fpregs_lock(); + + if (!test_thread_flag(TIF_NEED_FPU_LOAD)) { + if (!rdmsrl_safe(MSR_IA32_U_CET, &msr_val)) + wrmsrl(MSR_IA32_U_CET, msr_val & ~CET_WAIT_ENDBR); + } else { + struct cet_user_state *cet; + + /* + * If !TIF_NEED_FPU_LOAD and get_xsave_addr() returns zero, + * XFEATURE_CET_USER is in init state (cet is not active). + * Return zero status. + */ + cet = get_xsave_addr(¤t->thread.fpu.state.xsave, + XFEATURE_CET_USER); + if (cet) { + msr_val = cet->user_cet; + cet->user_cet = msr_val & ~CET_WAIT_ENDBR; + } + } + + fpregs_unlock(); + + return msr_val & CET_WAIT_ENDBR; +} + +int ibt_set_wait_endbr(void) +{ + if (!current->thread.shstk.ibt) + return 0; + + return ibt_set_clear_msr_bits(CET_WAIT_ENDBR, 0); +} diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c index 661e46803b84..a1285650852e 100644 --- a/arch/x86/kernel/signal.c +++ b/arch/x86/kernel/signal.c @@ -135,6 +135,9 @@ static int restore_sigcontext(struct pt_regs *regs, */ if (unlikely(!(uc_flags & UC_STRICT_RESTORE_SS) && user_64bit_mode(regs))) force_valid_ss(regs); + + if (uc_flags & UC_WAIT_ENDBR) + ibt_set_wait_endbr(); #endif return fpu__restore_sig((void __user *)sc.fpstate, @@ -455,6 +458,9 @@ static unsigned long frame_uc_flags(struct pt_regs *regs) if (likely(user_64bit_mode(regs))) flags |= UC_STRICT_RESTORE_SS; + if (ibt_get_clear_wait_endbr()) + flags |= UC_WAIT_ENDBR; + return flags; } From patchwork Mon Aug 30 18:22:15 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yu-cheng Yu X-Patchwork-Id: 12465785 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BCADDC432BE for ; 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Mon, 30 Aug 2021 18:23:13 +0000 (UTC) X-FDA: 78532569066.40.CB3C520 Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by imf11.hostedemail.com (Postfix) with ESMTP id 0941AF0000A8 for ; Mon, 30 Aug 2021 18:23:12 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10092"; a="282043658" X-IronPort-AV: E=Sophos;i="5.84,364,1620716400"; d="scan'208";a="282043658" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Aug 2021 11:23:10 -0700 X-IronPort-AV: E=Sophos;i="5.84,364,1620716400"; d="scan'208";a="540650954" Received: from yyu32-desk.sc.intel.com ([143.183.136.146]) by fmsmga002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Aug 2021 11:23:09 -0700 From: Yu-cheng Yu 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 , Oleg Nesterov , Pavel Machek , Peter Zijlstra , Randy Dunlap , "Ravi V. Shankar" , Dave Martin , Weijiang Yang , Pengfei Xu , Haitao Huang , Rick P Edgecombe Cc: Yu-cheng Yu Subject: [PATCH v30 04/10] x86/cet/ibt: Disable IBT for ia32 Date: Mon, 30 Aug 2021 11:22:15 -0700 Message-Id: <20210830182221.3535-5-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20210830182221.3535-1-yu-cheng.yu@intel.com> References: <20210830182221.3535-1-yu-cheng.yu@intel.com> MIME-Version: 1.0 Authentication-Results: imf11.hostedemail.com; dkim=none; spf=none (imf11.hostedemail.com: domain of yu-cheng.yu@intel.com has no SPF policy when checking 134.134.136.100) smtp.mailfrom=yu-cheng.yu@intel.com; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=intel.com (policy=none) X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 0941AF0000A8 X-Stat-Signature: gecgxz18x3f616kxbkytfbjakzkiok4j X-HE-Tag: 1630347792-577414 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: In a signal, a task's IBT status needs to be saved to the signal frame, and later restored in sigreturn. For the purpose, previous versions of the series add a new struct to the signal frame. However, a new signal frame format (or re-using a reserved space) introduces complex compatibility issues. In the discussion (see link below), Andy Lutomirski proposed using a ucontext flag. The approach is clean and eliminates most compatibility issues. However, a legacy IA32 signal frame does not have ucontext and cannot support a uc flag. Thus, - Disable IBT for ia32. - In ia32 sigreturn, verify ibt is disabled. Signed-off-by: Yu-cheng Yu Acked-by: Andy Lutomirski Cc: Cyrill Gorcunov Cc: Florian Weimer Cc: H. Peter Anvin Cc: Kees Cook Link: https://lore.kernel.org/linux-api/f6e61dae-9805-c855-8873-7481ceb7ea79@intel.com/ --- arch/x86/ia32/ia32_signal.c | 7 +++++++ arch/x86/include/asm/elf.h | 13 ++++++++++++- 2 files changed, 19 insertions(+), 1 deletion(-) diff --git a/arch/x86/ia32/ia32_signal.c b/arch/x86/ia32/ia32_signal.c index 77d0fa90cc19..946039cb3150 100644 --- a/arch/x86/ia32/ia32_signal.c +++ b/arch/x86/ia32/ia32_signal.c @@ -104,6 +104,13 @@ COMPAT_SYSCALL_DEFINE0(sigreturn) struct sigframe_ia32 __user *frame = (struct sigframe_ia32 __user *)(regs->sp-8); sigset_t set; + /* + * Verify legacy sigreturn does not have IBT enabled. + */ +#ifdef CONFIG_X86_IBT + if (current->thread.shstk.ibt) + goto badframe; +#endif if (!access_ok(frame, sizeof(*frame))) goto badframe; if (__get_user(set.sig[0], &frame->sc.oldmask) diff --git a/arch/x86/include/asm/elf.h b/arch/x86/include/asm/elf.h index 3281a3d01bd2..cf9eeb30c00c 100644 --- a/arch/x86/include/asm/elf.h +++ b/arch/x86/include/asm/elf.h @@ -6,6 +6,7 @@ * ELF register definitions.. */ #include +#include #include #include @@ -403,7 +404,17 @@ struct arch_elf_state { } #define arch_elf_pt_proc(ehdr, phdr, elf, interp, state) (0) -#define arch_check_elf(ehdr, interp, interp_ehdr, state) (0) +static inline int arch_check_elf(void *ehdr, bool interp, + void *interp_ehdr, + struct arch_elf_state *state) +{ + /* + * Disable IBT for ia32 + */ + if (elf_check_arch_ia32((struct elf32_hdr *)ehdr)) + state->gnu_property &= ~GNU_PROPERTY_X86_FEATURE_1_IBT; + return 0; +} /* Do not change the values. See get_align_mask() */ enum align_flags { From patchwork Mon Aug 30 18:22:16 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yu-cheng Yu X-Patchwork-Id: 12465787 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CE048C432BE for ; Mon, 30 Aug 2021 18:23:24 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 86E7860FD9 for ; Mon, 30 Aug 2021 18:23:24 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 86E7860FD9 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 895BC6B0081; Mon, 30 Aug 2021 14:23:14 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 81D01900002; Mon, 30 Aug 2021 14:23:14 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 51AFF6B0082; Mon, 30 Aug 2021 14:23:14 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0210.hostedemail.com [216.40.44.210]) by kanga.kvack.org (Postfix) with ESMTP id 245BF900002 for ; Mon, 30 Aug 2021 14:23:14 -0400 (EDT) Received: from smtpin08.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id DB42F2702C for ; Mon, 30 Aug 2021 18:23:13 +0000 (UTC) X-FDA: 78532569066.08.2061ABB Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by imf03.hostedemail.com (Postfix) with ESMTP id 6958630000A9 for ; Mon, 30 Aug 2021 18:23:13 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10092"; a="282043664" X-IronPort-AV: E=Sophos;i="5.84,364,1620716400"; d="scan'208";a="282043664" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Aug 2021 11:23:10 -0700 X-IronPort-AV: E=Sophos;i="5.84,364,1620716400"; d="scan'208";a="540650956" Received: from yyu32-desk.sc.intel.com ([143.183.136.146]) by fmsmga002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Aug 2021 11:23:09 -0700 From: Yu-cheng Yu 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 , Oleg Nesterov , Pavel Machek , Peter Zijlstra , Randy Dunlap , "Ravi V. Shankar" , Dave Martin , Weijiang Yang , Pengfei Xu , Haitao Huang , Rick P Edgecombe Cc: Yu-cheng Yu Subject: [PATCH v30 05/10] x86/cet/ibt: Update ELF header parsing for Indirect Branch Tracking Date: Mon, 30 Aug 2021 11:22:16 -0700 Message-Id: <20210830182221.3535-6-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20210830182221.3535-1-yu-cheng.yu@intel.com> References: <20210830182221.3535-1-yu-cheng.yu@intel.com> MIME-Version: 1.0 Authentication-Results: imf03.hostedemail.com; dkim=none; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=intel.com (policy=none); spf=none (imf03.hostedemail.com: domain of yu-cheng.yu@intel.com has no SPF policy when checking 134.134.136.100) smtp.mailfrom=yu-cheng.yu@intel.com X-Stat-Signature: 1jwfr877qr6g4wauq3m1wj8wnns3557f X-Rspamd-Queue-Id: 6958630000A9 X-Rspamd-Server: rspam04 X-HE-Tag: 1630347793-101905 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: An ELF file's .note.gnu.property indicates features the file supports. The property is parsed at loading time and passed to arch_setup_elf_ property(). Update it for Indirect Branch Tracking. Signed-off-by: Yu-cheng Yu Cc: Kees Cook --- v27: - Remove selecting of ARCH_USE_GNU_PROPERTY and ARCH_BINFMT_ELF_STATE, since they are already selected by X86_64. --- arch/x86/kernel/process_64.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index 4271963fdd8c..4ab751a5146e 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -884,6 +884,12 @@ int arch_setup_elf_property(struct arch_elf_state *state) if (state->gnu_property & GNU_PROPERTY_X86_FEATURE_1_SHSTK) r = shstk_setup(); + + if (r < 0) + return r; + + if (state->gnu_property & GNU_PROPERTY_X86_FEATURE_1_IBT) + r = ibt_setup(); #endif return r; From patchwork Mon Aug 30 18:22:17 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yu-cheng Yu X-Patchwork-Id: 12465789 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C339DC4320E for ; Mon, 30 Aug 2021 18:23:26 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 6306460243 for ; Mon, 30 Aug 2021 18:23:26 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 6306460243 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id D4FA96B0083; Mon, 30 Aug 2021 14:23:14 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D00C7900002; Mon, 30 Aug 2021 14:23:14 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id BC99C6B0085; Mon, 30 Aug 2021 14:23:14 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0048.hostedemail.com [216.40.44.48]) by kanga.kvack.org (Postfix) with ESMTP id 8409A900003 for ; Mon, 30 Aug 2021 14:23:14 -0400 (EDT) Received: from smtpin11.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 405AB2203D for ; Mon, 30 Aug 2021 18:23:14 +0000 (UTC) X-FDA: 78532569108.11.1686C58 Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by imf11.hostedemail.com (Postfix) with ESMTP id B7D37F0000A1 for ; Mon, 30 Aug 2021 18:23:13 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10092"; a="282043670" X-IronPort-AV: E=Sophos;i="5.84,364,1620716400"; d="scan'208";a="282043670" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Aug 2021 11:23:10 -0700 X-IronPort-AV: E=Sophos;i="5.84,364,1620716400"; d="scan'208";a="540650960" Received: from yyu32-desk.sc.intel.com ([143.183.136.146]) by fmsmga002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Aug 2021 11:23:10 -0700 From: Yu-cheng Yu 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 , Oleg Nesterov , Pavel Machek , Peter Zijlstra , Randy Dunlap , "Ravi V. Shankar" , Dave Martin , Weijiang Yang , Pengfei Xu , Haitao Huang , Rick P Edgecombe Cc: Yu-cheng Yu Subject: [PATCH v30 06/10] x86/cet/ibt: Update arch_prctl functions for Indirect Branch Tracking Date: Mon, 30 Aug 2021 11:22:17 -0700 Message-Id: <20210830182221.3535-7-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20210830182221.3535-1-yu-cheng.yu@intel.com> References: <20210830182221.3535-1-yu-cheng.yu@intel.com> MIME-Version: 1.0 Authentication-Results: imf11.hostedemail.com; dkim=none; spf=none (imf11.hostedemail.com: domain of yu-cheng.yu@intel.com has no SPF policy when checking 134.134.136.100) smtp.mailfrom=yu-cheng.yu@intel.com; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=intel.com (policy=none) X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: B7D37F0000A1 X-Stat-Signature: zadxdtzeuj8ngtdm3pmq4yioa3es3dtz X-HE-Tag: 1630347793-826806 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: "H.J. Lu" Update ARCH_X86_CET_STATUS and ARCH_X86_CET_DISABLE for Indirect Branch Tracking. Signed-off-by: H.J. Lu Signed-off-by: Yu-cheng Yu Reviewed-by: Kees Cook --- arch/x86/kernel/cet_prctl.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/x86/kernel/cet_prctl.c b/arch/x86/kernel/cet_prctl.c index b426d200e070..bd3c80d402e7 100644 --- a/arch/x86/kernel/cet_prctl.c +++ b/arch/x86/kernel/cet_prctl.c @@ -22,6 +22,9 @@ static int cet_copy_status_to_user(struct thread_shstk *shstk, u64 __user *ubuf) buf[2] = shstk->size; } + if (shstk->ibt) + buf[0] |= GNU_PROPERTY_X86_FEATURE_1_IBT; + return copy_to_user(ubuf, buf, sizeof(buf)); } @@ -46,6 +49,8 @@ int prctl_cet(int option, u64 arg2) return -EINVAL; if (arg2 & GNU_PROPERTY_X86_FEATURE_1_SHSTK) shstk_disable(); + if (arg2 & GNU_PROPERTY_X86_FEATURE_1_IBT) + ibt_disable(); return 0; case ARCH_X86_CET_LOCK: From patchwork Mon Aug 30 18:22:18 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yu-cheng Yu X-Patchwork-Id: 12465793 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A70CEC4320A for ; Mon, 30 Aug 2021 18:23:30 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 5CE1260FD9 for ; Mon, 30 Aug 2021 18:23:30 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 5CE1260FD9 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 586A16B0085; Mon, 30 Aug 2021 14:23:15 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 536BC900003; Mon, 30 Aug 2021 14:23:15 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 2FA266B0087; Mon, 30 Aug 2021 14:23:15 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0031.hostedemail.com [216.40.44.31]) by kanga.kvack.org (Postfix) with ESMTP id F3110900004 for ; Mon, 30 Aug 2021 14:23:14 -0400 (EDT) Received: from smtpin06.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 9A7D38249980 for ; Mon, 30 Aug 2021 18:23:14 +0000 (UTC) X-FDA: 78532569108.06.61C5B33 Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by imf28.hostedemail.com (Postfix) with ESMTP id 25C78900009A for ; Mon, 30 Aug 2021 18:23:13 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10092"; a="282043673" X-IronPort-AV: E=Sophos;i="5.84,364,1620716400"; d="scan'208";a="282043673" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Aug 2021 11:23:10 -0700 X-IronPort-AV: E=Sophos;i="5.84,364,1620716400"; d="scan'208";a="540650963" Received: from yyu32-desk.sc.intel.com ([143.183.136.146]) by fmsmga002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Aug 2021 11:23:10 -0700 From: Yu-cheng Yu 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 , Oleg Nesterov , Pavel Machek , Peter Zijlstra , Randy Dunlap , "Ravi V. Shankar" , Dave Martin , Weijiang Yang , Pengfei Xu , Haitao Huang , Rick P Edgecombe Cc: Yu-cheng Yu Subject: [PATCH v30 07/10] x86/vdso: Insert endbr32/endbr64 to vDSO Date: Mon, 30 Aug 2021 11:22:18 -0700 Message-Id: <20210830182221.3535-8-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20210830182221.3535-1-yu-cheng.yu@intel.com> References: <20210830182221.3535-1-yu-cheng.yu@intel.com> MIME-Version: 1.0 X-Rspamd-Queue-Id: 25C78900009A Authentication-Results: imf28.hostedemail.com; dkim=none; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=intel.com (policy=none); spf=none (imf28.hostedemail.com: domain of yu-cheng.yu@intel.com has no SPF policy when checking 134.134.136.100) smtp.mailfrom=yu-cheng.yu@intel.com X-Rspamd-Server: rspam01 X-Stat-Signature: n35bbudrfccme61dddodsjkkwuyx9f6m X-HE-Tag: 1630347793-467573 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: "H.J. Lu" When Indirect Branch Tracking (IBT) is enabled, vDSO entry points need ENDBR32/ENDBR64 as first instructions. Kconfig X86_IBT verifies compiler's -fcf-protection support. Update vDso Makefile to enable it. Signed-off-by: H.J. Lu Signed-off-by: Yu-cheng Yu Reviewed-by: Kees Cook Cc: Andy Lutomirski --- arch/x86/entry/vdso/Makefile | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile index 05c4abc2fdfd..a773a5f03b63 100644 --- a/arch/x86/entry/vdso/Makefile +++ b/arch/x86/entry/vdso/Makefile @@ -93,6 +93,10 @@ endif $(vobjs): KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_LTO) $(GCC_PLUGINS_CFLAGS) $(RETPOLINE_CFLAGS),$(KBUILD_CFLAGS)) $(CFL) +ifdef CONFIG_X86_IBT +$(vobjs) $(vobjs32): KBUILD_CFLAGS += -fcf-protection=branch +endif + # # vDSO code runs in userspace and -pg doesn't help with profiling anyway. # From patchwork Mon Aug 30 18:22:19 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yu-cheng Yu X-Patchwork-Id: 12465795 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8699BC4320E for ; Mon, 30 Aug 2021 18:23:32 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 4107260243 for ; Mon, 30 Aug 2021 18:23:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 4107260243 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 80C3A6B0087; Mon, 30 Aug 2021 14:23:15 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 6980B900004; Mon, 30 Aug 2021 14:23:15 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 4C003900002; Mon, 30 Aug 2021 14:23:15 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0074.hostedemail.com [216.40.44.74]) by kanga.kvack.org (Postfix) with ESMTP id E2C64900003 for ; Mon, 30 Aug 2021 14:23:14 -0400 (EDT) Received: from smtpin24.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 9F48D26814 for ; Mon, 30 Aug 2021 18:23:14 +0000 (UTC) X-FDA: 78532569108.24.1ED04A2 Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by imf03.hostedemail.com (Postfix) with ESMTP id 1537D30000A5 for ; Mon, 30 Aug 2021 18:23:13 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10092"; a="282043675" X-IronPort-AV: E=Sophos;i="5.84,364,1620716400"; d="scan'208";a="282043675" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Aug 2021 11:23:10 -0700 X-IronPort-AV: E=Sophos;i="5.84,364,1620716400"; d="scan'208";a="540650965" Received: from yyu32-desk.sc.intel.com ([143.183.136.146]) by fmsmga002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Aug 2021 11:23:10 -0700 From: Yu-cheng Yu 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 , Oleg Nesterov , Pavel Machek , Peter Zijlstra , Randy Dunlap , "Ravi V. Shankar" , Dave Martin , Weijiang Yang , Pengfei Xu , Haitao Huang , Rick P Edgecombe Cc: Yu-cheng Yu , Jarkko Sakkinen Subject: [PATCH v30 08/10] x86/vdso: Introduce ENDBR macro Date: Mon, 30 Aug 2021 11:22:19 -0700 Message-Id: <20210830182221.3535-9-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20210830182221.3535-1-yu-cheng.yu@intel.com> References: <20210830182221.3535-1-yu-cheng.yu@intel.com> MIME-Version: 1.0 Authentication-Results: imf03.hostedemail.com; dkim=none; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=intel.com (policy=none); spf=none (imf03.hostedemail.com: domain of yu-cheng.yu@intel.com has no SPF policy when checking 134.134.136.100) smtp.mailfrom=yu-cheng.yu@intel.com X-Stat-Signature: izukp8kg7dqtr8613g66q7rgeh3qitxz X-Rspamd-Queue-Id: 1537D30000A5 X-Rspamd-Server: rspam04 X-HE-Tag: 1630347793-15824 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: ENDBR is a special new instruction for the Indirect Branch Tracking (IBT) component of CET. IBT prevents attacks by ensuring that (most) indirect branches and function calls may only land at ENDBR instructions. Branches that don't follow the rules will result in control flow (#CF) exceptions. ENDBR is a noop when IBT is unsupported or disabled. Most ENDBR instructions are inserted automatically by the compiler, but branch targets written in assembly must have ENDBR added manually. Introduce ENDBR64/ENDBR32 macros. Signed-off-by: Yu-cheng Yu Reviewed-by: Kees Cook Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Dave Hansen Cc: Jarkko Sakkinen Cc: Peter Zijlstra --- arch/x86/include/asm/vdso.h | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/vdso.h b/arch/x86/include/asm/vdso.h index 98aa103eb4ab..97358246e4c7 100644 --- a/arch/x86/include/asm/vdso.h +++ b/arch/x86/include/asm/vdso.h @@ -52,6 +52,24 @@ extern int map_vdso_once(const struct vdso_image *image, unsigned long addr); extern bool fixup_vdso_exception(struct pt_regs *regs, int trapnr, unsigned long error_code, unsigned long fault_addr); -#endif /* __ASSEMBLER__ */ +#else /* __ASSEMBLER__ */ + +/* + * ENDBR is an instruction for the Indirect Branch Tracking (IBT) component + * of CET. IBT prevents attacks by ensuring that (most) indirect branches + * function calls may only land at ENDBR instructions. Branches that don't + * follow the rules will result in control flow (#CF) exceptions. + * ENDBR is a noop when IBT is unsupported or disabled. Most ENDBR + * instructions are inserted automatically by the compiler, but branch + * targets written in assembly must have ENDBR added manually. + */ +#ifdef CONFIG_X86_IBT +#define ENDBR64 endbr64 +#define ENDBR32 endbr32 +#else +#define ENDBR64 +#define ENDBR32 +#endif +#endif /* __ASSEMBLER__ */ #endif /* _ASM_X86_VDSO_H */ From patchwork Mon Aug 30 18:22:20 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yu-cheng Yu X-Patchwork-Id: 12465791 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CA97CC432BE for ; Mon, 30 Aug 2021 18:23:28 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 7D80460243 for ; Mon, 30 Aug 2021 18:23:28 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 7D80460243 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 1380A6B0082; Mon, 30 Aug 2021 14:23:15 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 0C7F4900002; Mon, 30 Aug 2021 14:23:14 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D4DF66B0082; Mon, 30 Aug 2021 14:23:14 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0112.hostedemail.com [216.40.44.112]) by kanga.kvack.org (Postfix) with ESMTP id 8A5306B0082 for ; Mon, 30 Aug 2021 14:23:14 -0400 (EDT) Received: from smtpin02.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 50FF7181AF5C1 for ; Mon, 30 Aug 2021 18:23:14 +0000 (UTC) X-FDA: 78532569108.02.692F140 Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by imf06.hostedemail.com (Postfix) with ESMTP id C43DD801A89B for ; Mon, 30 Aug 2021 18:23:12 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10092"; a="218047646" X-IronPort-AV: E=Sophos;i="5.84,364,1620716400"; d="scan'208";a="218047646" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Aug 2021 11:23:11 -0700 X-IronPort-AV: E=Sophos;i="5.84,364,1620716400"; d="scan'208";a="540650969" Received: from yyu32-desk.sc.intel.com ([143.183.136.146]) by fmsmga002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Aug 2021 11:23:10 -0700 From: Yu-cheng Yu 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 , Oleg Nesterov , Pavel Machek , Peter Zijlstra , Randy Dunlap , "Ravi V. Shankar" , Dave Martin , Weijiang Yang , Pengfei Xu , Haitao Huang , Rick P Edgecombe Cc: Yu-cheng Yu Subject: [PATCH v30 09/10] x86/vdso/32: Add ENDBR to __kernel_vsyscall entry point Date: Mon, 30 Aug 2021 11:22:20 -0700 Message-Id: <20210830182221.3535-10-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20210830182221.3535-1-yu-cheng.yu@intel.com> References: <20210830182221.3535-1-yu-cheng.yu@intel.com> MIME-Version: 1.0 X-Rspamd-Queue-Id: C43DD801A89B Authentication-Results: imf06.hostedemail.com; dkim=none; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=intel.com (policy=none); spf=none (imf06.hostedemail.com: domain of yu-cheng.yu@intel.com has no SPF policy when checking 192.55.52.115) smtp.mailfrom=yu-cheng.yu@intel.com X-Rspamd-Server: rspam01 X-Stat-Signature: 4ua4kh3nz854km47zff4c1gmnp89e4ma X-HE-Tag: 1630347792-952741 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: "H.J. Lu" ENDBR is a special new instruction for the Indirect Branch Tracking (IBT) component of CET. IBT prevents attacks by ensuring that (most) indirect branches and function calls may only land at ENDBR instructions. Branches that don't follow the rules will result in control flow (#CF) exceptions. ENDBR is a noop when IBT is unsupported or disabled. Most ENDBR instructions are inserted automatically by the compiler, but branch targets written in assembly must have ENDBR added manually. Add that to __kernel_vsyscall entry point. Signed-off-by: H.J. Lu Signed-off-by: Yu-cheng Yu Reviewed-by: Kees Cook Cc: Andy Lutomirski --- arch/x86/entry/vdso/vdso32/system_call.S | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/x86/entry/vdso/vdso32/system_call.S b/arch/x86/entry/vdso/vdso32/system_call.S index 6ddd7a937b3e..d321c2ded33a 100644 --- a/arch/x86/entry/vdso/vdso32/system_call.S +++ b/arch/x86/entry/vdso/vdso32/system_call.S @@ -7,6 +7,7 @@ #include #include #include +#include .text .globl __kernel_vsyscall @@ -14,6 +15,7 @@ ALIGN __kernel_vsyscall: CFI_STARTPROC + ENDBR32 /* * Reshuffle regs so that all of any of the entry instructions * will preserve enough state. From patchwork Mon Aug 30 18:22:21 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yu-cheng Yu X-Patchwork-Id: 12465783 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 964FBC4320E for ; Mon, 30 Aug 2021 18:23:20 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 4ACE760FA0 for ; Mon, 30 Aug 2021 18:23:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 4ACE760FA0 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 031468D0002; Mon, 30 Aug 2021 14:23:14 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id F22AD6B0082; Mon, 30 Aug 2021 14:23:13 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id DA98A8D0002; Mon, 30 Aug 2021 14:23:13 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0125.hostedemail.com [216.40.44.125]) by kanga.kvack.org (Postfix) with ESMTP id CAF3E6B0080 for ; Mon, 30 Aug 2021 14:23:13 -0400 (EDT) Received: from smtpin36.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 8147526DF0 for ; Mon, 30 Aug 2021 18:23:13 +0000 (UTC) X-FDA: 78532569066.36.FAB023F Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by imf14.hostedemail.com (Postfix) with ESMTP id A321B6001986 for ; Mon, 30 Aug 2021 18:23:12 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10092"; a="205547535" X-IronPort-AV: E=Sophos;i="5.84,364,1620716400"; d="scan'208";a="205547535" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Aug 2021 11:23:11 -0700 X-IronPort-AV: E=Sophos;i="5.84,364,1620716400"; d="scan'208";a="540650971" Received: from yyu32-desk.sc.intel.com ([143.183.136.146]) by fmsmga002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Aug 2021 11:23:11 -0700 From: Yu-cheng Yu 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 , Oleg Nesterov , Pavel Machek , Peter Zijlstra , Randy Dunlap , "Ravi V. Shankar" , Dave Martin , Weijiang Yang , Pengfei Xu , Haitao Huang , Rick P Edgecombe Cc: Yu-cheng Yu , Jarkko Sakkinen Subject: [PATCH v30 10/10] x86/vdso: Add ENDBR to __vdso_sgx_enter_enclave Date: Mon, 30 Aug 2021 11:22:21 -0700 Message-Id: <20210830182221.3535-11-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20210830182221.3535-1-yu-cheng.yu@intel.com> References: <20210830182221.3535-1-yu-cheng.yu@intel.com> MIME-Version: 1.0 Authentication-Results: imf14.hostedemail.com; dkim=none; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=intel.com (policy=none); spf=none (imf14.hostedemail.com: domain of yu-cheng.yu@intel.com has no SPF policy when checking 134.134.136.20) smtp.mailfrom=yu-cheng.yu@intel.com X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: A321B6001986 X-Stat-Signature: o5gywf9reamxkytof7o3kfyfuwhshdhp X-HE-Tag: 1630347792-991615 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: ENDBR is a special new instruction for the Indirect Branch Tracking (IBT) component of CET. IBT prevents attacks by ensuring that (most) indirect branches and function calls may only land at ENDBR instructions. Branches that don't follow the rules will result in control flow (#CF) exceptions. ENDBR is a noop when IBT is unsupported or disabled. Most ENDBR instructions are inserted automatically by the compiler, but branch targets written in assembly must have ENDBR added manually. Add ENDBR to __vdso_sgx_enter_enclave() indirect branch targets, including EEXIT, which is considered an indirect branch. Signed-off-by: Yu-cheng Yu Reviewed-by: Kees Cook Acked-by: Jarkko Sakkinen Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Dave Hansen Cc: Peter Zijlstra --- v28: - Move ENDBR64 below EEXIT comment (no functional change). - Update change log, state EEXIT is considered an indirect branch. --- arch/x86/entry/vdso/vsgx.S | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/x86/entry/vdso/vsgx.S b/arch/x86/entry/vdso/vsgx.S index 99dafac992e2..d65a7f9dea8b 100644 --- a/arch/x86/entry/vdso/vsgx.S +++ b/arch/x86/entry/vdso/vsgx.S @@ -4,6 +4,7 @@ #include #include #include +#include #include "extable.h" @@ -27,6 +28,7 @@ SYM_FUNC_START(__vdso_sgx_enter_enclave) /* Prolog */ .cfi_startproc + ENDBR64 push %rbp .cfi_adjust_cfa_offset 8 .cfi_rel_offset %rbp, 0 @@ -64,6 +66,7 @@ SYM_FUNC_START(__vdso_sgx_enter_enclave) enclu /* EEXIT jumps here unless the enclave is doing something fancy. */ + ENDBR64 mov SGX_ENCLAVE_OFFSET_OF_RUN(%rbp), %rbx /* Set exit_reason. */ @@ -91,6 +94,7 @@ SYM_FUNC_START(__vdso_sgx_enter_enclave) jmp .Lout .Lhandle_exception: + ENDBR64 mov SGX_ENCLAVE_OFFSET_OF_RUN(%rbp), %rbx /* Set the exception info. */