From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754568AbbHIKXQ (ORCPT ); Sun, 9 Aug 2015 06:23:16 -0400 Received: from terminus.zytor.com ([198.137.202.10]:36009 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754487AbbHIKXL (ORCPT ); Sun, 9 Aug 2015 06:23:11 -0400 Date: Sun, 9 Aug 2015 03:22:20 -0700 From: tip-bot for Juergen Gross Message-ID: Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, tglx@linutronix.de, peterz@infradead.org, jgross@suse.com, torvalds@linux-foundation.org, luto@kernel.org, mingo@kernel.org Reply-To: jgross@suse.com, torvalds@linux-foundation.org, peterz@infradead.org, hpa@zytor.com, tglx@linutronix.de, linux-kernel@vger.kernel.org, mingo@kernel.org, luto@kernel.org In-Reply-To: <1438848278-12906-1-git-send-email-jgross@suse.com> References: <1438848278-12906-1-git-send-email-jgross@suse.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/urgent] x86/ldt: Correct LDT access in single stepping logic Git-Commit-ID: 136d9d83c07c5e30ac49fc83b27e8c4842f108fc 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 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 136d9d83c07c5e30ac49fc83b27e8c4842f108fc Gitweb: http://git.kernel.org/tip/136d9d83c07c5e30ac49fc83b27e8c4842f108fc Author: Juergen Gross AuthorDate: Thu, 6 Aug 2015 10:04:38 +0200 Committer: Ingo Molnar CommitDate: Sat, 8 Aug 2015 10:20:45 +0200 x86/ldt: Correct LDT access in single stepping logic Commit 37868fe113ff ("x86/ldt: Make modify_ldt synchronous") introduced a new struct ldt_struct anchored at mm->context.ldt. convert_ip_to_linear() was changed to reflect this, but indexing into the ldt has to be changed as the pointer is no longer void *. Signed-off-by: Juergen Gross Reviewed-by: Andy Lutomirski Cc: # On top of: 37868fe113ff: x86/ldt: Make modify_ldt synchronous Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: bp@suse.de Link: http://lkml.kernel.org/r/1438848278-12906-1-git-send-email-jgross@suse.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/step.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/step.c b/arch/x86/kernel/step.c index 6273324..0ccb53a 100644 --- a/arch/x86/kernel/step.c +++ b/arch/x86/kernel/step.c @@ -28,11 +28,11 @@ unsigned long convert_ip_to_linear(struct task_struct *child, struct pt_regs *re struct desc_struct *desc; unsigned long base; - seg &= ~7UL; + seg >>= 3; mutex_lock(&child->mm->context.lock); if (unlikely(!child->mm->context.ldt || - (seg >> 3) >= child->mm->context.ldt->size)) + seg >= child->mm->context.ldt->size)) addr = -1L; /* bogus selector, access would fault */ else { desc = &child->mm->context.ldt->entries[seg];