From patchwork Tue Mar 13 20:59:40 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Garnier X-Patchwork-Id: 10280807 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id A2883602C2 for ; Tue, 13 Mar 2018 21:06:28 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8FCFA21327 for ; Tue, 13 Mar 2018 21:06:28 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 832FA284C3; Tue, 13 Mar 2018 21:06:28 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.3 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.wl.linuxfoundation.org (Postfix) with SMTP id 58F3C284BD for ; Tue, 13 Mar 2018 21:06:27 +0000 (UTC) Received: (qmail 22266 invoked by uid 550); 13 Mar 2018 21:01:33 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 21897 invoked from network); 13 Mar 2018 21:01:18 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=o8FwWxS6UvZt8S381bV/6SjaKIoBzPvD2Ads8iAWii0=; b=UyjBLQ3fZb0dN20Eumm4a8sQ2rHZ3sKl5TYWP+6KEXMwInVVtVx5BGj3tJjLiodaVi ibyW6gUaEQXpclPm7DeIHf2ZdyhCH/aEd1tdJgZJvR2NFmq5AmUDEZOnndDZyLEo5suA BNet/thF4eD4VuK4lxHxsbwv8SqQOBmnu8YBrFOBIZ+K9l3RH70fIac3NgmbWv4l+AOB W57drKtmf+vDpa7nACbJ+13Rbsr0aYTe+FYB8+uNJLq8CvP+Xj8MHewoHo7KHIKTp29K Gb03nRaQ4In6R3+/Jg67/DJQXGJBGn3ZgwWFJMTwg7uRZTml8ybZZdu2DWLgE717eLL9 pctg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=o8FwWxS6UvZt8S381bV/6SjaKIoBzPvD2Ads8iAWii0=; b=A/Tb1k5u5LwbErZuNJ3mPEB9C1qOg8Higdf7SUt24hznYnQD2et7GUQyPTjkUJGVft pUeKsWMmpDju9Dqlf6BfWM1FSEXXFaIU7RRXRdahEy23cFbLrJ8p+P1lOEodGSxv55fm HccPF+P42v7PaGiPb74oHffpMieIvt+BGDvwR9Am+6785JC7Ukg99PSfQRvaK2OQgQuY OVaUa05wUezXiga6Ra27c3gl9W1BV94fEvDrVkeyRSDNALYCYFQ2sUUCVNUUuDondFDo /H7gLUR3IHITY+46U2ftKlZq3w1LaCM/S+CEWLyPVvDPykiVwRew8OOSuqyLkB6H0uZp KGAA== X-Gm-Message-State: AElRT7FqwnPpwXL7C+6UaviiPJ/llCNfeVCPvGxqIzYSK8N/fD5Y4slB Kz6KP4a9XXhpOmrrEOCL9oULyg== X-Google-Smtp-Source: AG47ELu48sL4zFQSbb2xuKWsZZVeSplhRIfANxIp6XY/jXVjzXRI7TUIPYKzzE8ish9IBl3TlcfJkQ== X-Received: by 2002:a17:902:51ee:: with SMTP id y101-v6mr1728825plh.157.1520974865532; Tue, 13 Mar 2018 14:01:05 -0700 (PDT) From: Thomas Garnier To: Herbert Xu , "David S . Miller" , Thomas Gleixner , Ingo Molnar , "H . Peter Anvin" , Peter Zijlstra , Josh Poimboeuf , Greg Kroah-Hartman , Kate Stewart , Thomas Garnier , Arnd Bergmann , Philippe Ombredanne , Arnaldo Carvalho de Melo , Andrey Ryabinin , Matthias Kaehlcke , Kees Cook , Tom Lendacky , "Kirill A . Shutemov" , Andy Lutomirski , Dominik Brodowski , Borislav Petkov , Borislav Petkov , "Rafael J . Wysocki" , Len Brown , Pavel Machek , Juergen Gross , Alok Kataria , Steven Rostedt , Tejun Heo , Christoph Lameter , Dennis Zhou , Boris Ostrovsky , David Woodhouse , Alexey Dobriyan , "Paul E . McKenney" , Andrew Morton , Nicolas Pitre , Randy Dunlap , "Luis R . Rodriguez" , Christopher Li , Jason Baron , Ashish Kalra , Kyle McMartin , Dou Liyang , Lukas Wunner , Petr Mladek , Sergey Senozhatsky , Masahiro Yamada , Ingo Molnar , Nicholas Piggin , Cao jin , "H . J . Lu" , Paolo Bonzini , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , Joerg Roedel , Dave Hansen , Rik van Riel , Jia Zhang , Jiri Slaby , Kyle Huey , Jonathan Corbet , Matthew Wilcox , Michal Hocko , Rob Landley , Baoquan He , Daniel Micay , =?UTF-8?q?Jan=20H=20=2E=20Sch=C3=B6nherr?= Cc: x86@kernel.org, linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, virtualization@lists.linux-foundation.org, xen-devel@lists.xenproject.org, linux-arch@vger.kernel.org, linux-sparse@vger.kernel.org, kvm@vger.kernel.org, linux-doc@vger.kernel.org, kernel-hardening@lists.openwall.com Subject: [PATCH v2 22/27] x86/modules: Add option to start module section after kernel Date: Tue, 13 Mar 2018 13:59:40 -0700 Message-Id: <20180313205945.245105-23-thgarnie@google.com> X-Mailer: git-send-email 2.16.2.660.g709887971b-goog In-Reply-To: <20180313205945.245105-1-thgarnie@google.com> References: <20180313205945.245105-1-thgarnie@google.com> X-Virus-Scanned: ClamAV using ClamSMTP Add an option so the module section is just after the mapped kernel. It will ensure position independent modules are always at the right distance from the kernel and do not require mcmodule=large. It also optimize the available size for modules by getting rid of the empty space on kernel randomization range. Signed-off-by: Thomas Garnier --- Documentation/x86/x86_64/mm.txt | 3 +++ arch/x86/Kconfig | 4 ++++ arch/x86/include/asm/pgtable_64_types.h | 6 ++++++ arch/x86/kernel/head64.c | 5 ++++- arch/x86/mm/dump_pagetables.c | 3 ++- 5 files changed, 19 insertions(+), 2 deletions(-) diff --git a/Documentation/x86/x86_64/mm.txt b/Documentation/x86/x86_64/mm.txt index ea91cb61a602..ec1dfe4c3cfe 100644 --- a/Documentation/x86/x86_64/mm.txt +++ b/Documentation/x86/x86_64/mm.txt @@ -77,3 +77,6 @@ Their order is preserved but their base will be offset early at boot time. Be very careful vs. KASLR when changing anything here. The KASLR address range must not overlap with anything except the KASAN shadow area, which is correct as KASAN disables KASLR. + +If CONFIG_DYNAMIC_MODULE_BASE is enabled, the module section follows the end of +the mapped kernel. diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 0cb1ae187c3e..df4134fd3247 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2236,6 +2236,10 @@ config RANDOMIZE_MEMORY_PHYSICAL_PADDING If unsure, leave at the default value. +# Module section starts just after the end of the kernel module +config DYNAMIC_MODULE_BASE + bool + config X86_GLOBAL_STACKPROTECTOR bool "Stack cookie using a global variable" depends on CC_STACKPROTECTOR_AUTO diff --git a/arch/x86/include/asm/pgtable_64_types.h b/arch/x86/include/asm/pgtable_64_types.h index d5c21a382475..d4d3b21d5b3d 100644 --- a/arch/x86/include/asm/pgtable_64_types.h +++ b/arch/x86/include/asm/pgtable_64_types.h @@ -7,6 +7,7 @@ #ifndef __ASSEMBLY__ #include #include +#include /* * These are used to make use of C type-checking.. @@ -126,7 +127,12 @@ extern unsigned int ptrs_per_p4d; #define VMALLOC_END (VMALLOC_START + (VMALLOC_SIZE_TB << 40) - 1) +#ifdef CONFIG_DYNAMIC_MODULE_BASE +#define MODULES_VADDR ALIGN(((unsigned long)_end + PAGE_SIZE), PMD_SIZE) +#else #define MODULES_VADDR (__START_KERNEL_map + KERNEL_IMAGE_SIZE) +#endif + /* The module sections ends with the start of the fixmap */ #define MODULES_END _AC(0xffffffffff000000, UL) #define MODULES_LEN (MODULES_END - MODULES_VADDR) diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index 2fe60e661227..ea4c498369d8 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -384,12 +384,15 @@ asmlinkage __visible void __init x86_64_start_kernel(char * real_mode_data) * Build-time sanity checks on the kernel image and module * area mappings. (these are purely build-time and produce no code) */ +#ifndef CONFIG_DYNAMIC_MODULE_BASE BUILD_BUG_ON(MODULES_VADDR < __START_KERNEL_map); BUILD_BUG_ON(MODULES_VADDR - __START_KERNEL_map < KERNEL_IMAGE_SIZE); - BUILD_BUG_ON(MODULES_LEN + KERNEL_IMAGE_SIZE > 2*PUD_SIZE); + BUILD_BUG_ON(!IS_ENABLED(CONFIG_RANDOMIZE_BASE_LARGE) && + MODULES_LEN + KERNEL_IMAGE_SIZE > 2*PUD_SIZE); BUILD_BUG_ON((__START_KERNEL_map & ~PMD_MASK) != 0); BUILD_BUG_ON((MODULES_VADDR & ~PMD_MASK) != 0); BUILD_BUG_ON(!(MODULES_VADDR > __START_KERNEL)); +#endif MAYBE_BUILD_BUG_ON(!(((MODULES_END - 1) & PGDIR_MASK) == (__START_KERNEL & PGDIR_MASK))); BUILD_BUG_ON(__fix_to_virt(__end_of_fixed_addresses) <= MODULES_END); diff --git a/arch/x86/mm/dump_pagetables.c b/arch/x86/mm/dump_pagetables.c index 62a7e9f65dec..6f0b1fa2a71a 100644 --- a/arch/x86/mm/dump_pagetables.c +++ b/arch/x86/mm/dump_pagetables.c @@ -104,7 +104,7 @@ static struct addr_marker address_markers[] = { [EFI_END_NR] = { EFI_VA_END, "EFI Runtime Services" }, #endif [HIGH_KERNEL_NR] = { __START_KERNEL_map, "High Kernel Mapping" }, - [MODULES_VADDR_NR] = { MODULES_VADDR, "Modules" }, + [MODULES_VADDR_NR] = { 0/*MODULES_VADDR*/, "Modules" }, [MODULES_END_NR] = { MODULES_END, "End Modules" }, [FIXADDR_START_NR] = { FIXADDR_START, "Fixmap Area" }, [END_OF_SPACE_NR] = { -1, NULL } @@ -599,6 +599,7 @@ static int __init pt_dump_init(void) address_markers[KASAN_SHADOW_START_NR].start_address = KASAN_SHADOW_START; address_markers[KASAN_SHADOW_END_NR].start_address = KASAN_SHADOW_END; #endif + address_markers[MODULES_VADDR_NR].start_address = MODULES_VADDR; #endif #ifdef CONFIG_X86_32 address_markers[VMALLOC_START_NR].start_address = VMALLOC_START;