From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751801AbaESW6p (ORCPT ); Mon, 19 May 2014 18:58:45 -0400 Received: from mail-pa0-f43.google.com ([209.85.220.43]:51451 "EHLO mail-pa0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751237AbaESW6m (ORCPT ); Mon, 19 May 2014 18:58:42 -0400 From: Andy Lutomirski To: x86@kernel.org, Andrew Morton , Sasha Levin , "linux-mm@kvack.org" , Dave Jones Cc: LKML , Cyrill Gorcunov , Pavel Emelyanov , "H. Peter Anvin" , Andy Lutomirski , Stefani Seibold Subject: [PATCH 1/4] x86,vdso: Fix an OOPS accessing the hpet mapping w/o an hpet Date: Mon, 19 May 2014 15:58:31 -0700 Message-Id: X-Mailer: git-send-email 1.9.0 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The oops can be triggered in qemu using -no-hpet (but not nohpet) by reading a couple of pages past the end of the vdso text. This should send SIGBUS instead of OOPSing. The bug was introduced by: commit 7a59ed415f5b57469e22e41fc4188d5399e0b194 Author: Stefani Seibold Date: Mon Mar 17 23:22:09 2014 +0100 x86, vdso: Add 32 bit VDSO time support for 32 bit kernel which is new in 3.15. This will be fixed separately in 3.15, but that patch will not apply to tip/x86/vdso. This is the equivalent fix for tip/x86/vdso and, presumably, 3.16. Cc: Stefani Seibold Reported-by: Sasha Levin Signed-off-by: Andy Lutomirski --- arch/x86/vdso/vma.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/vdso/vma.c b/arch/x86/vdso/vma.c index e915eae..8ad0081 100644 --- a/arch/x86/vdso/vma.c +++ b/arch/x86/vdso/vma.c @@ -90,6 +90,7 @@ static int map_vdso(const struct vdso_image *image, bool calculate_addr) struct vm_area_struct *vma; unsigned long addr; int ret = 0; + static struct page *no_pages[] = {NULL}; if (calculate_addr) { addr = vdso_addr(current->mm->start_stack, @@ -125,7 +126,7 @@ static int map_vdso(const struct vdso_image *image, bool calculate_addr) addr + image->size, image->sym_end_mapping - image->size, VM_READ, - NULL); + no_pages); if (IS_ERR(vma)) { ret = PTR_ERR(vma); -- 1.9.0 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f43.google.com (mail-pa0-f43.google.com [209.85.220.43]) by kanga.kvack.org (Postfix) with ESMTP id 4747D6B0037 for ; Mon, 19 May 2014 18:58:43 -0400 (EDT) Received: by mail-pa0-f43.google.com with SMTP id hz1so6435716pad.30 for ; Mon, 19 May 2014 15:58:42 -0700 (PDT) Received: from mail-pa0-f41.google.com (mail-pa0-f41.google.com [209.85.220.41]) by mx.google.com with ESMTPS id gl4si4839583pbb.46.2014.05.19.15.58.42 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Mon, 19 May 2014 15:58:42 -0700 (PDT) Received: by mail-pa0-f41.google.com with SMTP id lj1so6406065pab.14 for ; Mon, 19 May 2014 15:58:42 -0700 (PDT) From: Andy Lutomirski Subject: [PATCH 1/4] x86,vdso: Fix an OOPS accessing the hpet mapping w/o an hpet Date: Mon, 19 May 2014 15:58:31 -0700 Message-Id: In-Reply-To: References: In-Reply-To: References: Sender: owner-linux-mm@kvack.org List-ID: To: x86@kernel.org, Andrew Morton , Sasha Levin , "linux-mm@kvack.org" , Dave Jones Cc: LKML , Cyrill Gorcunov , Pavel Emelyanov , "H. Peter Anvin" , Andy Lutomirski , Stefani Seibold The oops can be triggered in qemu using -no-hpet (but not nohpet) by reading a couple of pages past the end of the vdso text. This should send SIGBUS instead of OOPSing. The bug was introduced by: commit 7a59ed415f5b57469e22e41fc4188d5399e0b194 Author: Stefani Seibold Date: Mon Mar 17 23:22:09 2014 +0100 x86, vdso: Add 32 bit VDSO time support for 32 bit kernel which is new in 3.15. This will be fixed separately in 3.15, but that patch will not apply to tip/x86/vdso. This is the equivalent fix for tip/x86/vdso and, presumably, 3.16. Cc: Stefani Seibold Reported-by: Sasha Levin Signed-off-by: Andy Lutomirski --- arch/x86/vdso/vma.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/vdso/vma.c b/arch/x86/vdso/vma.c index e915eae..8ad0081 100644 --- a/arch/x86/vdso/vma.c +++ b/arch/x86/vdso/vma.c @@ -90,6 +90,7 @@ static int map_vdso(const struct vdso_image *image, bool calculate_addr) struct vm_area_struct *vma; unsigned long addr; int ret = 0; + static struct page *no_pages[] = {NULL}; if (calculate_addr) { addr = vdso_addr(current->mm->start_stack, @@ -125,7 +126,7 @@ static int map_vdso(const struct vdso_image *image, bool calculate_addr) addr + image->size, image->sym_end_mapping - image->size, VM_READ, - NULL); + no_pages); if (IS_ERR(vma)) { ret = PTR_ERR(vma); -- 1.9.0 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org