Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936133AbZLQBsj (ORCPT ); Wed, 16 Dec 2009 20:48:39 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S936119AbZLQBs3 (ORCPT ); Wed, 16 Dec 2009 20:48:29 -0500 Received: from kroah.org ([198.145.64.141]:47761 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1763579AbZLQBTy (ORCPT ); Wed, 16 Dec 2009 20:19:54 -0500 X-Mailbox-Line: From gregkh@mini.kroah.org Wed Dec 16 17:15:59 2009 Message-Id: <20091217011559.279090025@mini.kroah.org> User-Agent: quilt/0.48-1 Date: Wed, 16 Dec 2009 17:14:22 -0800 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Andi Kleen , Andrew Morton , Nick Piggin , Darren Hart , Peter Zijlstra , Thomas Gleixner Subject: [11/90] futex: Take mmap_sem for get_user_pages in fault_in_user_writeable In-Reply-To: <20091217011835.GA20434@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1447 Lines: 43 2.6.31-stable review patch. If anyone has any objections, please let us know. ------------------ From: Andi Kleen commit 722d0172377a5697919b9f7e5beb95165b1dec4e upstream. get_user_pages() must be called with mmap_sem held. Signed-off-by: Andi Kleen Cc: Andrew Morton Cc: Nick Piggin Cc: Darren Hart Cc: Peter Zijlstra LKML-Reference: <20091208121942.GA21298@basil.fritz.box> Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman --- kernel/futex.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) --- a/kernel/futex.c +++ b/kernel/futex.c @@ -303,8 +303,14 @@ void put_futex_key(int fshared, union fu */ static int fault_in_user_writeable(u32 __user *uaddr) { - int ret = get_user_pages(current, current->mm, (unsigned long)uaddr, - 1, 1, 0, NULL, NULL); + struct mm_struct *mm = current->mm; + int ret; + + down_read(&mm->mmap_sem); + ret = get_user_pages(current, mm, (unsigned long)uaddr, + 1, 1, 0, NULL, NULL); + up_read(&mm->mmap_sem); + return ret < 0 ? ret : 0; } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/