From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758115Ab3GMDWE (ORCPT ); Fri, 12 Jul 2013 23:22:04 -0400 Received: from terminus.zytor.com ([198.137.202.10]:43953 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757969Ab3GMDWB (ORCPT ); Fri, 12 Jul 2013 23:22:01 -0400 Date: Fri, 12 Jul 2013 20:21:39 -0700 From: tip-bot for Kees Cook Message-ID: Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@kernel.org, keescook@chromium.org, pageexec@gmail.com, tglx@linutronix.de, hpa@linux.intel.com Reply-To: mingo@kernel.org, hpa@zytor.com, linux-kernel@vger.kernel.org, keescook@chromium.org, pageexec@gmail.com, tglx@linutronix.de, hpa@linux.intel.com In-Reply-To: <20130712225017.GA5366@www.outflux.net> References: <20130712225017.GA5366@www.outflux.net> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/urgent] x86: Make sure IDT is page aligned Git-Commit-ID: c0b3450f101523a49823fa93d155f1d258e5ac6f X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.7 (terminus.zytor.com [127.0.0.1]); Fri, 12 Jul 2013 20:21:45 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: c0b3450f101523a49823fa93d155f1d258e5ac6f Gitweb: http://git.kernel.org/tip/c0b3450f101523a49823fa93d155f1d258e5ac6f Author: Kees Cook AuthorDate: Fri, 12 Jul 2013 15:50:17 -0700 Committer: H. Peter Anvin CommitDate: Fri, 12 Jul 2013 16:14:08 -0700 x86: Make sure IDT is page aligned Since the IDT is referenced from a fixmap, make sure it is page aligned. Merge with 32-bit one, since it was already aligned to deal with F00F bug. This avoids the risk of it ever being moved in the bss and having the mapping be offset, resulting in calling incorrect handlers. [ hpa: It isn't clear that this is a manifest bug in any way, but tagging for -stable because it shouldn't hurt and might avoid some very hard-to-debug breakages due to unrelated changes. ] Signed-off-by: Kees Cook Link: http://lkml.kernel.org/r/20130712225017.GA5366@www.outflux.net Reported-by: PaX Team Cc: stable@vger.kernel.org Signed-off-by: H. Peter Anvin --- arch/x86/kernel/head_64.S | 4 ---- arch/x86/kernel/traps.c | 7 ++----- 2 files changed, 2 insertions(+), 9 deletions(-) diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 5e4d8a8..317b8cc 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -514,10 +514,6 @@ ENTRY(phys_base) .section .bss, "aw", @nobits .align L1_CACHE_BYTES -ENTRY(idt_table) - .skip IDT_ENTRIES * 16 - - .align L1_CACHE_BYTES ENTRY(debug_idt_table) .skip IDT_ENTRIES * 16 diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index b0865e8..0952614 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -68,13 +68,10 @@ #include asmlinkage int system_call(void); +#endif -/* - * The IDT has to be page-aligned to simplify the Pentium - * F0 0F bug workaround. - */ +/* The IDT has to be page-aligned to keep it aligned with its fixmap. */ gate_desc idt_table[NR_VECTORS] __page_aligned_data = { { { { 0, 0 } } }, }; -#endif DECLARE_BITMAP(used_vectors, NR_VECTORS); EXPORT_SYMBOL_GPL(used_vectors);