From patchwork Sun Jan 30 21:18:36 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Edgecombe, Rick P" X-Patchwork-Id: 12730163 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 83F84C433F5 for ; Sun, 30 Jan 2022 21:22:45 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C2F136B00C2; Sun, 30 Jan 2022 16:22:14 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id BDCD96B00C3; Sun, 30 Jan 2022 16:22:14 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A0B146B00C4; Sun, 30 Jan 2022 16:22:14 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0007.hostedemail.com [216.40.44.7]) by kanga.kvack.org (Postfix) with ESMTP id 8E3A66B00C2 for ; Sun, 30 Jan 2022 16:22:14 -0500 (EST) Received: from smtpin09.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 4A363181E7875 for ; Sun, 30 Jan 2022 21:22:14 +0000 (UTC) X-FDA: 79088226588.09.2983769 Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by imf08.hostedemail.com (Postfix) with ESMTP id B1E0E160004 for ; Sun, 30 Jan 2022 21:22:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1643577733; x=1675113733; h=from:to:cc:subject:date:message-id:in-reply-to: references; bh=G4fVgUiNuZ57ki/aV9t4t6lONJ9wFjRKKu+IxwPcJt0=; b=AH5Xkx4kinVdVgP887QGXU3JehV+c3k9QvTfZohb/vUtGfKnHrZhjijE zkOT3vTXmBuwSbB4uwyjj1CiYVb4MzaV5hJrcyYf/tOl7kxmcpGLwveRm MnI7XrlDIoZ74E4x7My/u2jYM5uvBsNUvnmHsEQwaUKES1bq99H/1toi+ CBkwzK0xRMfxE3nsjAXEKF6+ZngRYlzfIrEBgTNQkUlC3EwlBiRJSRo8X e8nW1TBHQMflA0geAcFfRbdS+GACBC7Nl/uDh7dPOkV0A7DzPBGo9QjJS YUPsi46saDzucYCfmqwViLUz30Es35OpjT8LlxpMV657Zpex8Ki291fd7 Q==; X-IronPort-AV: E=McAfee;i="6200,9189,10243"; a="244970236" X-IronPort-AV: E=Sophos;i="5.88,329,1635231600"; d="scan'208";a="244970236" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Jan 2022 13:22:13 -0800 X-IronPort-AV: E=Sophos;i="5.88,329,1635231600"; d="scan'208";a="536857008" Received: from avmallar-mobl1.amr.corp.intel.com (HELO rpedgeco-desk.amr.corp.intel.com) ([10.209.123.171]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Jan 2022 13:22:12 -0800 From: Rick Edgecombe 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 , "Kirill A . Shutemov" , joao.moreira@intel.com, John Allen , kcc@google.com, eranian@google.com Cc: rick.p.edgecombe@intel.com, Yu@kvack.org, Yu-cheng Subject: [PATCH 33/35] selftests/x86: Add map_shadow_stack syscall test Date: Sun, 30 Jan 2022 13:18:36 -0800 Message-Id: <20220130211838.8382-34-rick.p.edgecombe@intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20220130211838.8382-1-rick.p.edgecombe@intel.com> References: <20220130211838.8382-1-rick.p.edgecombe@intel.com> X-Rspamd-Queue-Id: B1E0E160004 X-Rspam-User: nil Authentication-Results: imf08.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=AH5Xkx4k; dmarc=pass (policy=none) header.from=intel.com; spf=none (imf08.hostedemail.com: domain of rick.p.edgecombe@intel.com has no SPF policy when checking 192.55.52.93) smtp.mailfrom=rick.p.edgecombe@intel.com X-Stat-Signature: jz8e7q3z1k56ymy3ndzajaicfwys4ace X-Rspamd-Server: rspam08 X-HE-Tag: 1643577733-253413 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: Add a simple selftest for exercising the new map_shadow_stack syscall. Co-developed-by: Yu, Yu-cheng Signed-off-by: Yu, Yu-cheng Signed-off-by: Rick Edgecombe --- v1: - New patch. tools/testing/selftests/x86/Makefile | 9 ++- .../selftests/x86/test_map_shadow_stack.c | 75 +++++++++++++++++++ 2 files changed, 83 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/x86/test_map_shadow_stack.c diff --git a/tools/testing/selftests/x86/Makefile b/tools/testing/selftests/x86/Makefile index 8a1f62ab3c8e..9114943336f9 100644 --- a/tools/testing/selftests/x86/Makefile +++ b/tools/testing/selftests/x86/Makefile @@ -9,11 +9,13 @@ UNAME_M := $(shell uname -m) CAN_BUILD_I386 := $(shell ./check_cc.sh $(CC) trivial_32bit_program.c -m32) CAN_BUILD_X86_64 := $(shell ./check_cc.sh $(CC) trivial_64bit_program.c) CAN_BUILD_WITH_NOPIE := $(shell ./check_cc.sh $(CC) trivial_program.c -no-pie) +CAN_BUILD_WITH_SHSTK := $(shell ./check_cc.sh $(CC) trivial_program.c -mshstk -fcf-protection) TARGETS_C_BOTHBITS := single_step_syscall sysret_ss_attrs syscall_nt test_mremap_vdso \ check_initial_reg_state sigreturn iopl ioperm \ test_vsyscall mov_ss_trap \ - syscall_arg_fault fsgsbase_restore sigaltstack + syscall_arg_fault fsgsbase_restore sigaltstack \ + test_map_shadow_stack TARGETS_C_32BIT_ONLY := entry_from_vm86 test_syscall_vdso unwind_vdso \ test_FCMOV test_FCOMI test_FISTTP \ vdso_restorer @@ -105,3 +107,8 @@ $(OUTPUT)/test_syscall_vdso_32: thunks_32.S # state. $(OUTPUT)/check_initial_reg_state_32: CFLAGS += -Wl,-ereal_start -static $(OUTPUT)/check_initial_reg_state_64: CFLAGS += -Wl,-ereal_start -static + +ifeq ($(CAN_BUILD_WITH_SHSTK),1) +$(OUTPUT)/test_map_shadow_stack_64: CFLAGS += -mshstk -fcf-protection +$(OUTPUT)/test_map_shadow_stack_32: CFLAGS += -mshstk -fcf-protection +endif \ No newline at end of file diff --git a/tools/testing/selftests/x86/test_map_shadow_stack.c b/tools/testing/selftests/x86/test_map_shadow_stack.c new file mode 100644 index 000000000000..dfd94ef0176d --- /dev/null +++ b/tools/testing/selftests/x86/test_map_shadow_stack.c @@ -0,0 +1,75 @@ +// SPDX-License-Identifier: GPL-2.0 + +#define _GNU_SOURCE + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define SS_SIZE 0x200000 + +void *create_shstk(void) +{ + return (void *)syscall(__NR_map_shadow_stack, SS_SIZE, SHADOW_STACK_SET_TOKEN); +} + +#if (__GNUC__ < 8) || (__GNUC__ == 8 && __GNUC_MINOR__ < 5) +int main(int argc, char *argv[]) +{ + printf("SKIP: compiler does not support CET."); + return 0; +} +#else +void try_shstk(unsigned long new_ssp) +{ + unsigned long ssp0, ssp1; + + printf("pid=%d\n", getpid()); + printf("new_ssp = %lx, *new_ssp = %lx\n", + new_ssp, *((unsigned long *)new_ssp)); + + ssp0 = _get_ssp(); + printf("changing ssp from %lx to %lx\n", ssp0, new_ssp); + + /* Make sure is aligned to 8 bytes */ + if ((ssp0 & 0xf) != 0) + ssp0 &= -8; + + asm volatile("rstorssp (%0)\n":: "r" (new_ssp)); + asm volatile("saveprevssp"); + ssp1 = _get_ssp(); + printf("ssp is now %lx\n", ssp1); + + ssp0 -= 8; + asm volatile("rstorssp (%0)\n":: "r" (ssp0)); + asm volatile("saveprevssp"); +} + +int main(int argc, char *argv[]) +{ + void *shstk; + + if (!_get_ssp()) { + printf("SKIP: shadow stack disabled."); + return 0; + } + + shstk = create_shstk(); + if (shstk == MAP_FAILED) { + printf("FAIL: Error creating shadow stack: %d\n", errno); + return 1; + } + try_shstk((unsigned long)shstk + SS_SIZE - 8); + + printf("PASS.\n"); + return 0; +} +#endif