From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934642Ab1KCBli (ORCPT ); Wed, 2 Nov 2011 21:41:38 -0400 Received: from cantor2.suse.de ([195.135.220.15]:51316 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934598Ab1KCBlb (ORCPT ); Wed, 2 Nov 2011 21:41:31 -0400 X-Mailbox-Line: From gregkh@clark.kroah.org Wed Nov 2 15:27:45 2011 Message-Id: <20111102222745.512746709@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Wed, 02 Nov 2011 15:26:47 -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, Serge Hallyn Subject: [063/101] USB: pid_ns: ensure pid is not freed during kill_pid_info_as_uid In-Reply-To: <20111102222755.GA10893@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.33-longterm review patch. If anyone has any objections, please let us know. ------------------ From: Serge Hallyn commit aec01c5895051849ed842dc5b8794017a7751f28 upstream. Alan Stern points out that after spin_unlock(&ps->lock) there is no guarantee that ps->pid won't be freed. Since kill_pid_info_as_uid() is called after the spin_unlock(), the pid passed to it must be pinned. Reported-by: Alan Stern Signed-off-by: Serge Hallyn Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/devio.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/drivers/usb/core/devio.c +++ b/drivers/usb/core/devio.c @@ -403,7 +403,7 @@ static void async_completed(struct urb * sinfo.si_errno = as->status; sinfo.si_code = SI_ASYNCIO; sinfo.si_addr = as->userurb; - pid = as->pid; + pid = get_pid(as->pid); uid = as->uid; euid = as->euid; secid = as->secid; @@ -416,9 +416,11 @@ static void async_completed(struct urb * cancel_bulk_urbs(ps, as->bulk_addr); spin_unlock(&ps->lock); - if (signr) + if (signr) { kill_pid_info_as_uid(sinfo.si_signo, &sinfo, pid, uid, euid, secid); + put_pid(pid); + } wake_up(&ps->wait); }