From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761168AbbA1ERk (ORCPT ); Tue, 27 Jan 2015 23:17:40 -0500 Received: from mail.kernel.org ([198.145.29.136]:38161 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761139AbbA1ERh (ORCPT ); Tue, 27 Jan 2015 23:17:37 -0500 From: lizf@kernel.org To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Ben Hutchings , Thomas Gleixner , Zefan Li Subject: [PATCH 3.4 044/177] x86: Reject x32 executables if x32 ABI not supported Date: Wed, 28 Jan 2015 12:07:35 +0800 Message-Id: <1422418236-12852-88-git-send-email-lizf@kernel.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1422418050-12581-1-git-send-email-lizf@kernel.org> References: <1422418050-12581-1-git-send-email-lizf@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ben Hutchings 3.4.106-rc1 review patch. If anyone has any objections, please let me know. ------------------ commit 0e6d3112a4e95d55cf6dca88f298d5f4b8f29bd1 upstream. It is currently possible to execve() an x32 executable on an x86_64 kernel that has only ia32 compat enabled. However all its syscalls will fail, even _exit(). This usually causes it to segfault. Change the ELF compat architecture check so that x32 executables are rejected if we don't support the x32 ABI. Signed-off-by: Ben Hutchings Link: http://lkml.kernel.org/r/1410120305.6822.9.camel@decadent.org.uk Signed-off-by: Thomas Gleixner Signed-off-by: Zefan Li --- arch/x86/include/asm/elf.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/elf.h b/arch/x86/include/asm/elf.h index 5939f44..06ec1fe 100644 --- a/arch/x86/include/asm/elf.h +++ b/arch/x86/include/asm/elf.h @@ -155,8 +155,9 @@ do { \ #define elf_check_arch(x) \ ((x)->e_machine == EM_X86_64) -#define compat_elf_check_arch(x) \ - (elf_check_arch_ia32(x) || (x)->e_machine == EM_X86_64) +#define compat_elf_check_arch(x) \ + (elf_check_arch_ia32(x) || \ + (IS_ENABLED(CONFIG_X86_X32_ABI) && (x)->e_machine == EM_X86_64)) #if __USER32_DS != __USER_DS # error "The following code assumes __USER32_DS == __USER_DS" -- 1.9.1