Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751243AbdCHHrz (ORCPT ); Wed, 8 Mar 2017 02:47:55 -0500 Received: from mx1.redhat.com ([209.132.183.28]:37408 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750757AbdCHHrv (ORCPT ); Wed, 8 Mar 2017 02:47:51 -0500 From: Baoquan He To: linux-kernel@vger.kernel.org Cc: linux-efi@vger.kernel.org, thgarnie@google.com, keescook@chromium.org, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, x86@kernel.org, akpm@linux-foundation.org, dyoung@redhat.com, Baoquan He Subject: [PATCH 2/2] x86/mm/KASLR: Correct the upper boundary of KALSR mm regions if adjacent to EFI Date: Wed, 8 Mar 2017 15:47:38 +0800 Message-Id: <1488959258-4731-2-git-send-email-bhe@redhat.com> In-Reply-To: <1488959258-4731-1-git-send-email-bhe@redhat.com> References: <1488959258-4731-1-git-send-email-bhe@redhat.com> X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.25]); Wed, 08 Mar 2017 07:47:49 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1335 Lines: 36 EFI allocates runtime services regions top-down, starting from EFI_VA_START to EFI_VA_END. So EFI_VA_START is bigger than EFI_VA_END and is the end of EFI region. The upper boundary of memory regions randomized by KASLR should be EFI_VA_END if it's adjacent to EFI region, but not EFI_VA_START. Correct it in this patch. Signed-off-by: Baoquan He --- arch/x86/mm/kaslr.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c index 887e571..aed2064 100644 --- a/arch/x86/mm/kaslr.c +++ b/arch/x86/mm/kaslr.c @@ -48,7 +48,7 @@ static const unsigned long vaddr_start = __PAGE_OFFSET_BASE; #if defined(CONFIG_X86_ESPFIX64) static const unsigned long vaddr_end = ESPFIX_BASE_ADDR; #elif defined(CONFIG_EFI) -static const unsigned long vaddr_end = EFI_VA_START; +static const unsigned long vaddr_end = EFI_VA_END; #else static const unsigned long vaddr_end = __START_KERNEL_map; #endif @@ -105,7 +105,7 @@ void __init kernel_randomize_memory(void) */ BUILD_BUG_ON(vaddr_start >= vaddr_end); BUILD_BUG_ON(IS_ENABLED(CONFIG_X86_ESPFIX64) && - vaddr_end >= EFI_VA_START); + vaddr_end >= EFI_VA_END); BUILD_BUG_ON((IS_ENABLED(CONFIG_X86_ESPFIX64) || IS_ENABLED(CONFIG_EFI)) && vaddr_end >= __START_KERNEL_map); -- 2.5.5