From patchwork Thu Oct 17 03:03:39 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Christopherson X-Patchwork-Id: 11194711 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 18744139A for ; Thu, 17 Oct 2019 03:03:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EB75E21925 for ; Thu, 17 Oct 2019 03:03:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2392143AbfJQDDr (ORCPT ); Wed, 16 Oct 2019 23:03:47 -0400 Received: from mga01.intel.com ([192.55.52.88]:16893 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2392120AbfJQDDr (ORCPT ); Wed, 16 Oct 2019 23:03:47 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga101.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 16 Oct 2019 20:03:46 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.67,306,1566889200"; d="scan'208";a="195026860" Received: from sjchrist-coffee.jf.intel.com ([10.54.74.41]) by fmsmga008.fm.intel.com with ESMTP; 16 Oct 2019 20:03:46 -0700 From: Sean Christopherson To: Jarkko Sakkinen Cc: linux-sgx@vger.kernel.org, Cedric Xing , Andy Lutomirski Subject: [PATCH for_v2? v2 13/14] selftests/x86/sgx: Add check to verify exit handler stack alignment Date: Wed, 16 Oct 2019 20:03:39 -0700 Message-Id: <20191017030340.18301-14-sean.j.christopherson@intel.com> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20191017030340.18301-1-sean.j.christopherson@intel.com> References: <20191017030340.18301-1-sean.j.christopherson@intel.com> MIME-Version: 1.0 Sender: linux-sgx-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org Add an assembly trampoline to the basic exit handler to snapshot the pre-CALL %rsp. Use the snapshot to verify that the stack is 16-byte aligned as required by the x86_64 ABI. Signed-off-by: Sean Christopherson --- tools/testing/selftests/x86/sgx/defines.h | 1 + tools/testing/selftests/x86/sgx/main.c | 20 +++++++++++++++++--- 2 files changed, 18 insertions(+), 3 deletions(-) diff --git a/tools/testing/selftests/x86/sgx/defines.h b/tools/testing/selftests/x86/sgx/defines.h index b303bcaeb8dd..c4d8b88f3d8a 100644 --- a/tools/testing/selftests/x86/sgx/defines.h +++ b/tools/testing/selftests/x86/sgx/defines.h @@ -15,6 +15,7 @@ typedef uint64_t u64; #define __aligned(x) __attribute__((__aligned__(x))) #define __packed __attribute__((packed)) +#define __used __attribute__((__used__)) /* Derived from asm-generic/bitsperlong.h. */ #if __x86_64__ diff --git a/tools/testing/selftests/x86/sgx/main.c b/tools/testing/selftests/x86/sgx/main.c index 0a4716cef486..5ebe25dc877c 100644 --- a/tools/testing/selftests/x86/sgx/main.c +++ b/tools/testing/selftests/x86/sgx/main.c @@ -342,14 +342,28 @@ static void test_sgx_vdso(struct sgx_secs *secs) EXPECT_EQ(exception.leaf, ENCLU_EENTER); } -static int basic_exit_handler(long rdi, long rsi, long rdx, long ursp, - long r8, long r9, void *tcs, int ret, - struct sgx_enclave_exception *e) +static int __used __basic_exit_handler(long rdi, long rsi, long rdx, long ursp, + long r8, long r9, void *tcs, int ret, + struct sgx_enclave_exception *e) { + ASSERT_RAW(!(r9 & 0xf), "Pre-CALL RSP not 16-byte aligned: %lx\n", r9); ASSERT_EQ(ret, 0); return 0; } +extern void *basic_exit_handler; + +static void __used basic_exit_handler_trampoline(void) +{ + /* Load the pre-CALL %rsp into %r9 to verify correct alignment. */ + asm volatile("1:\n\t" + "lea 0x8(%%rsp), %%r9\n\t" + "jmp __basic_exit_handler\n\t" + "basic_exit_handler: .quad 1b\n\t" + ".global basic_exit_handler" + ::: "memory"); +} + /* * Test the vDSO API, __vdso_sgx_enter_enclave(), with an exit handler. */