From mboxrd@z Thu Jan 1 00:00:00 1970 Reply-To: kernel-hardening@lists.openwall.com From: Thomas Garnier Date: Tue, 9 Aug 2016 10:11:04 -0700 Message-Id: <1470762665-88032-1-git-send-email-thgarnie@google.com> Subject: [kernel-hardening] [PATCH v4 1/2] x86/KASLR: Fix physical memory calculation on KASLR memory randomization To: Thomas Gleixner , Ingo Molnar , "H . Peter Anvin" , Borislav Petkov , Joerg Roedel , Dave Young , "Rafael J . Wysocki" , Lv Zheng , Thomas Garnier , Baoquan He , Dave Hansen , Mark Salter , Aleksey Makarov , Kees Cook , Andrew Morton , Christian Borntraeger , Fabian Frederick , Toshi Kani , Dan Williams Cc: x86@kernel.org, linux-kernel@vger.kernel.org, kernel-hardening@lists.openwall.com List-ID: Initialize KASLR memory randomization after max_pfn is initialized. Also ensure the size is rounded up. It could have create problems on machines with more than 1Tb of memory on certain random addresses. Fixes: 021182e52fe0 ("Enable KASLR for physical mapping memory regions") Signed-off-by: Thomas Garnier --- Based on next-20160805 --- arch/x86/kernel/setup.c | 8 ++++++-- arch/x86/mm/kaslr.c | 2 +- 2 files changed, 7 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index bcabb88..dc50644 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -936,8 +936,6 @@ void __init setup_arch(char **cmdline_p) x86_init.oem.arch_setup(); - kernel_randomize_memory(); - iomem_resource.end = (1ULL << boot_cpu_data.x86_phys_bits) - 1; setup_memory_map(); parse_setup_data(); @@ -1055,6 +1053,12 @@ void __init setup_arch(char **cmdline_p) max_possible_pfn = max_pfn; + /* + * Define random base addresses for memory sections after max_pfn is + * defined and before each memory section base is used. + */ + kernel_randomize_memory(); + #ifdef CONFIG_X86_32 /* max_low_pfn get updated here */ find_low_pfn_range(); diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c index 26dccd6..ec8654f 100644 --- a/arch/x86/mm/kaslr.c +++ b/arch/x86/mm/kaslr.c @@ -97,7 +97,7 @@ void __init kernel_randomize_memory(void) * add padding if needed (especially for memory hotplug support). */ BUG_ON(kaslr_regions[0].base != &page_offset_base); - memory_tb = ((max_pfn << PAGE_SHIFT) >> TB_SHIFT) + + memory_tb = DIV_ROUND_UP(max_pfn << PAGE_SHIFT, 1UL << TB_SHIFT) + CONFIG_RANDOMIZE_MEMORY_PHYSICAL_PADDING; /* Adapt phyiscal memory region size based on available memory */ -- 2.8.0.rc3.226.g39d4020 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932518AbcHIRLg (ORCPT ); Tue, 9 Aug 2016 13:11:36 -0400 Received: from mail-pa0-f49.google.com ([209.85.220.49]:36851 "EHLO mail-pa0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932352AbcHIRLf (ORCPT ); Tue, 9 Aug 2016 13:11:35 -0400 From: Thomas Garnier To: Thomas Gleixner , Ingo Molnar , "H . Peter Anvin" , Borislav Petkov , Joerg Roedel , Dave Young , "Rafael J . Wysocki" , Lv Zheng , Thomas Garnier , Baoquan He , Dave Hansen , Mark Salter , Aleksey Makarov , Kees Cook , Andrew Morton , Christian Borntraeger , Fabian Frederick , Toshi Kani , Dan Williams Cc: x86@kernel.org, linux-kernel@vger.kernel.org, kernel-hardening@lists.openwall.com Subject: [PATCH v4 1/2] x86/KASLR: Fix physical memory calculation on KASLR memory randomization Date: Tue, 9 Aug 2016 10:11:04 -0700 Message-Id: <1470762665-88032-1-git-send-email-thgarnie@google.com> X-Mailer: git-send-email 2.8.0.rc3.226.g39d4020 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Initialize KASLR memory randomization after max_pfn is initialized. Also ensure the size is rounded up. It could have create problems on machines with more than 1Tb of memory on certain random addresses. Fixes: 021182e52fe0 ("Enable KASLR for physical mapping memory regions") Signed-off-by: Thomas Garnier --- Based on next-20160805 --- arch/x86/kernel/setup.c | 8 ++++++-- arch/x86/mm/kaslr.c | 2 +- 2 files changed, 7 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index bcabb88..dc50644 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -936,8 +936,6 @@ void __init setup_arch(char **cmdline_p) x86_init.oem.arch_setup(); - kernel_randomize_memory(); - iomem_resource.end = (1ULL << boot_cpu_data.x86_phys_bits) - 1; setup_memory_map(); parse_setup_data(); @@ -1055,6 +1053,12 @@ void __init setup_arch(char **cmdline_p) max_possible_pfn = max_pfn; + /* + * Define random base addresses for memory sections after max_pfn is + * defined and before each memory section base is used. + */ + kernel_randomize_memory(); + #ifdef CONFIG_X86_32 /* max_low_pfn get updated here */ find_low_pfn_range(); diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c index 26dccd6..ec8654f 100644 --- a/arch/x86/mm/kaslr.c +++ b/arch/x86/mm/kaslr.c @@ -97,7 +97,7 @@ void __init kernel_randomize_memory(void) * add padding if needed (especially for memory hotplug support). */ BUG_ON(kaslr_regions[0].base != &page_offset_base); - memory_tb = ((max_pfn << PAGE_SHIFT) >> TB_SHIFT) + + memory_tb = DIV_ROUND_UP(max_pfn << PAGE_SHIFT, 1UL << TB_SHIFT) + CONFIG_RANDOMIZE_MEMORY_PHYSICAL_PADDING; /* Adapt phyiscal memory region size based on available memory */ -- 2.8.0.rc3.226.g39d4020