From patchwork Wed Oct 4 21:20:00 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Garnier X-Patchwork-Id: 9985625 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 D411560586 for ; Wed, 4 Oct 2017 21:26:21 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C479728B68 for ; Wed, 4 Oct 2017 21:26:21 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B7CC528C2A; Wed, 4 Oct 2017 21:26:21 +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=-4.1 required=2.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, RCVD_IN_DNSWL_MED, T_DKIM_INVALID 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 D838128B68 for ; Wed, 4 Oct 2017 21:26:20 +0000 (UTC) Received: (qmail 17512 invoked by uid 550); 4 Oct 2017 21:21:50 -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 16280 invoked from network); 4 Oct 2017 21:21:42 -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=MdiH8KGLe4SAX82PTINyVHNuKb6EKJodK5xHIAzo4Ec=; b=BamnB9NwoYemWMdWjx3ynCpFzImLMfTMkf0430b3DrC/iIEFixNiXLnHe4misOVqct OXr0Erm3Ax+E2nODdImaN9h3/7R8CRbe4HvozDH1msA+euTbxVBLQ1XSZQtIDZtpsk05 N58uXlnojnb65ykuTz6GISocqRfTlMUCbV4m3cDPFpzIeRlHIEDxYsCg+wXMIwo6SCgH iYpTMdgRZsFfgNcC41lRcU0GuGsiBOFtxM/YwCCu3EinKr7e6w7NQoOtYh06Q1VWALvZ vHnOz3hXIRnzN7YfbIQ5/epdbU5HXqVVv+/CUPYJfTo/DMNdNu67+3itnJIkh3jQ0Y1k g73A== 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=MdiH8KGLe4SAX82PTINyVHNuKb6EKJodK5xHIAzo4Ec=; b=TrXQPPfw/R126qv03DZmlLYgjO/Qbt4Nlrlko1Oeb98zzEGwBcdrAdR1woGoKCLiVv Bgb40akb4iJiNo3fikNbOBgzKl6gzAiUGiwZO4xVLT9owx2AiJtMMoZwPZigW2qIzgR2 fmlXSdsDhD6GDxV0ythpCyI+I5zX627fIwFNrvZuSbu0zic+z12cDU5RKRCajADWb2Ls 1xWdonxxPQ0e+y6IV3s/hczwxy1uGpO+Z6QwwMFnuLpMvY0xZBVQ63AA5Jjm6TuWcd+j dBJj01qXymKDWgTY9fEvE1ZPIPiMgVi0EQRwrQt0vtOv3sCp3N61dyUb8a1LG9nC6Rlf QVFw== X-Gm-Message-State: AHPjjUgzNEE3J+kWP8GpRD+9BmwTk1xRHPc6g333MWMGjB9AnjRvWlDp OZIZ3K56BPltiC+dpB5XSSFWQw== X-Google-Smtp-Source: AOwi7QD1fa6RmP4ptiwgvQ1Srf1bJvX4WrGwqliBdkLyEN4oe3Umlsk/H0eo3QALO5DNDtwX1+npQw== X-Received: by 10.159.208.5 with SMTP id a5mr21449799plp.436.1507152089902; Wed, 04 Oct 2017 14:21:29 -0700 (PDT) From: Thomas Garnier To: Herbert Xu , "David S . Miller" , Thomas Gleixner , Ingo Molnar , "H . Peter Anvin" , Peter Zijlstra , Josh Poimboeuf , Thomas Garnier , Arnd Bergmann , Kees Cook , Matthias Kaehlcke , Tom Lendacky , Andy Lutomirski , "Kirill A . Shutemov" , Borislav Petkov , "Rafael J . Wysocki" , Len Brown , Pavel Machek , Juergen Gross , Chris Wright , Alok Kataria , Rusty Russell , Tejun Heo , Christoph Lameter , Boris Ostrovsky , Alexey Dobriyan , Andrew Morton , Paul Gortmaker , Chris Metcalf , "Paul E . McKenney" , Nicolas Pitre , Borislav Petkov , "Luis R . Rodriguez" , Greg Kroah-Hartman , Christopher Li , Steven Rostedt , Jason Baron , Dou Liyang , "Rafael J . Wysocki" , Mika Westerberg , Lukas Wunner , Masahiro Yamada , Alexei Starovoitov , Daniel Borkmann , Markus Trippelsdorf , Paolo Bonzini , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , Joerg Roedel , Rik van Riel , David Howells , Ard Biesheuvel , Waiman Long , Kyle Huey , Andrey Ryabinin , Jonathan Corbet , Matthew Wilcox , Michal Hocko , Peter Foley , Paul Bolle , Jiri Kosina , Rob Landley , "H . J . Lu" , Baoquan He , =?UTF-8?q?Jan=20H=20=2E=20Sch=C3=B6nherr?= , Daniel Micay 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 Date: Wed, 4 Oct 2017 14:20:00 -0700 Message-Id: <20171004212003.28296-25-thgarnie@google.com> X-Mailer: git-send-email 2.14.2.920.gcf0c67979c-goog In-Reply-To: <20171004212003.28296-1-thgarnie@google.com> References: <20171004212003.28296-1-thgarnie@google.com> Subject: [kernel-hardening] [RFC v3 24/27] x86/mm: Make the x86 GOT read-only X-Virus-Scanned: ClamAV using ClamSMTP The GOT is changed during early boot when relocations are applied. Make it read-only directly. This table exists only for PIE binary. Position Independent Executable (PIE) support will allow to extended the KASLR randomization range below the -2G memory limit. Signed-off-by: Thomas Garnier --- include/asm-generic/vmlinux.lds.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index e549bff87c5b..a2301c292e26 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -279,6 +279,17 @@ VMLINUX_SYMBOL(__end_ro_after_init) = .; #endif +#ifdef CONFIG_X86_PIE +#define RO_GOT_X86 \ + .got : AT(ADDR(.got) - LOAD_OFFSET) { \ + VMLINUX_SYMBOL(__start_got) = .; \ + *(.got); \ + VMLINUX_SYMBOL(__end_got) = .; \ + } +#else +#define RO_GOT_X86 +#endif + /* * Read only Data */ @@ -335,6 +346,7 @@ VMLINUX_SYMBOL(__end_builtin_fw) = .; \ } \ \ + RO_GOT_X86 \ TRACEDATA \ \ /* Kernel symbol table: Normal symbols */ \