From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932834AbeD0QFu (ORCPT ); Fri, 27 Apr 2018 12:05:50 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:43186 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1758629AbeD0QFq (ORCPT ); Fri, 27 Apr 2018 12:05:46 -0400 Date: Fri, 27 Apr 2018 19:05:45 +0300 From: "Michael S. Tsirkin" To: Kevin Easton Cc: Jason Wang , kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Subject: Re: [PATCH net] vhost: Use kzalloc() to allocate vhost_msg_node Message-ID: <20180427185501-mutt-send-email-mst@kernel.org> References: <000000000000a5b2b1056a86e98c@google.com> <20180427154502.GA22544@la.guarana.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180427154502.GA22544@la.guarana.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Apr 27, 2018 at 11:45:02AM -0400, Kevin Easton wrote: > The struct vhost_msg within struct vhost_msg_node is copied to userspace, > so it should be allocated with kzalloc() to ensure all structure padding > is zeroed. > > Signed-off-by: Kevin Easton > Reported-by: syzbot+87cfa083e727a224754b@syzkaller.appspotmail.com Does it help if a patch naming the padding is applied, and then we init just the relevant field? Just curious. > --- > drivers/vhost/vhost.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c > index f3bd8e9..1b84dcff 100644 > --- a/drivers/vhost/vhost.c > +++ b/drivers/vhost/vhost.c > @@ -2339,7 +2339,7 @@ EXPORT_SYMBOL_GPL(vhost_disable_notify); > /* Create a new message. */ > struct vhost_msg_node *vhost_new_msg(struct vhost_virtqueue *vq, int type) > { > - struct vhost_msg_node *node = kmalloc(sizeof *node, GFP_KERNEL); > + struct vhost_msg_node *node = kzalloc(sizeof *node, GFP_KERNEL); > if (!node) > return NULL; > node->vq = vq; > -- > 2.8.1