From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A9490C43140 for ; Thu, 21 Jun 2018 05:11:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5D50720883 for ; Thu, 21 Jun 2018 05:11:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5D50720883 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932620AbeFUFLj (ORCPT ); Thu, 21 Jun 2018 01:11:39 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:47004 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932278AbeFUFLh (ORCPT ); Thu, 21 Jun 2018 01:11:37 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 3A76D81A4EB6; Thu, 21 Jun 2018 05:11:37 +0000 (UTC) Received: from jason-ThinkPad-T450s.redhat.com (ovpn-12-33.pek2.redhat.com [10.72.12.33]) by smtp.corp.redhat.com (Postfix) with ESMTP id 27BEE2156880; Thu, 21 Jun 2018 05:11:33 +0000 (UTC) From: Jason Wang To: mst@redhat.com, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: dan.carpenter@oracle.com, Jason Wang Subject: [PATCH net] vhost_net: validate sock before trying to put its fd Date: Thu, 21 Jun 2018 13:11:31 +0800 Message-Id: <1529557891-4828-1-git-send-email-jasowang@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.6 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.8]); Thu, 21 Jun 2018 05:11:37 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.8]); Thu, 21 Jun 2018 05:11:37 +0000 (UTC) for IP:'10.11.54.6' DOMAIN:'int-mx06.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'jasowang@redhat.com' RCPT:'' Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Sock will be NULL if we pass -1 to vhost_net_set_backend(), but when we meet errors during ubuf allocation, the code does not check for NULL before calling sockfd_put(), this will lead NULL dereferencing. Fixing by checking sock pointer before. Fixes: bab632d69ee4 ("vhost: vhost TX zero-copy support") Reported-by: Dan Carpenter Signed-off-by: Jason Wang --- drivers/vhost/net.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index 986058a..b97a994 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -1208,7 +1208,8 @@ static long vhost_net_set_backend(struct vhost_net *n, unsigned index, int fd) if (ubufs) vhost_net_ubuf_put_wait_and_free(ubufs); err_ubufs: - sockfd_put(sock); + if (sock) + sockfd_put(sock); err_vq: mutex_unlock(&vq->mutex); err: -- 2.7.4