From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936165Ab2C3V6y (ORCPT ); Fri, 30 Mar 2012 17:58:54 -0400 Received: from mail-yw0-f46.google.com ([209.85.213.46]:50387 "EHLO mail-yw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965585Ab2C3VSE (ORCPT ); Fri, 30 Mar 2012 17:18:04 -0400 Message-Id: <20120330194829.803471367@linuxfoundation.org> User-Agent: quilt/0.60-19.1 Date: Fri, 30 Mar 2012 12:48:52 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Thomas Gleixner , Peter Zijlstra , Darren Hart Subject: [ 027/175] futex: Cover all PI opcodes with cmpxchg enabled check In-Reply-To: <20120330195801.GA31806@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.3-stable review patch. If anyone has any objections, please let me know. ------------------ From: Thomas Gleixner commit 59263b513c11398cd66a52d4c5b2b118ce1e0359 upstream. Some of the newer futex PI opcodes do not check the cmpxchg enabled variable and call unconditionally into the handling functions. Cover all PI opcodes in a separate check. Signed-off-by: Thomas Gleixner Cc: Peter Zijlstra Cc: Darren Hart Signed-off-by: Greg Kroah-Hartman --- kernel/futex.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-) --- a/kernel/futex.c +++ b/kernel/futex.c @@ -2641,6 +2641,16 @@ long do_futex(u32 __user *uaddr, int op, } switch (cmd) { + case FUTEX_LOCK_PI: + case FUTEX_UNLOCK_PI: + case FUTEX_TRYLOCK_PI: + case FUTEX_WAIT_REQUEUE_PI: + case FUTEX_CMP_REQUEUE_PI: + if (!futex_cmpxchg_enabled) + return -ENOSYS; + } + + switch (cmd) { case FUTEX_WAIT: val3 = FUTEX_BITSET_MATCH_ANY; case FUTEX_WAIT_BITSET: @@ -2661,16 +2671,13 @@ long do_futex(u32 __user *uaddr, int op, ret = futex_wake_op(uaddr, flags, uaddr2, val, val2, val3); break; case FUTEX_LOCK_PI: - if (futex_cmpxchg_enabled) - ret = futex_lock_pi(uaddr, flags, val, timeout, 0); + ret = futex_lock_pi(uaddr, flags, val, timeout, 0); break; case FUTEX_UNLOCK_PI: - if (futex_cmpxchg_enabled) - ret = futex_unlock_pi(uaddr, flags); + ret = futex_unlock_pi(uaddr, flags); break; case FUTEX_TRYLOCK_PI: - if (futex_cmpxchg_enabled) - ret = futex_lock_pi(uaddr, flags, 0, timeout, 1); + ret = futex_lock_pi(uaddr, flags, 0, timeout, 1); break; case FUTEX_WAIT_REQUEUE_PI: val3 = FUTEX_BITSET_MATCH_ANY;