From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752096AbeC0Dra (ORCPT ); Mon, 26 Mar 2018 23:47:30 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:40334 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751765AbeC0Dr3 (ORCPT ); Mon, 26 Mar 2018 23:47:29 -0400 From: Jason Wang To: mst@redhat.com, jasowang@redhat.com Cc: kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH net] vhost: correctly remove wait queue during poll failure Date: Tue, 27 Mar 2018 11:47:22 +0800 Message-Id: <1522122442-30317-1-git-send-email-jasowang@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org We tried to remove vq poll from wait queue, but do not check whether or not it was in a list before. This will lead double free. Fixing this by checking poll->wqh to make sure it was in a list. Reported-by: syzbot+c0272972b01b872e604a@syzkaller.appspotmail.com Fixes: 2b8b328b61c79 ("vhost_net: handle polling errors when setting backend") Signed-off-by: Jason Wang --- drivers/vhost/vhost.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 1b3e8d2d..5d5a9d9 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -212,8 +212,7 @@ int vhost_poll_start(struct vhost_poll *poll, struct file *file) if (mask) vhost_poll_wakeup(&poll->wait, 0, 0, poll_to_key(mask)); if (mask & EPOLLERR) { - if (poll->wqh) - remove_wait_queue(poll->wqh, &poll->wait); + vhost_poll_stop(poll); ret = -EINVAL; } -- 2.7.4