From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752878AbcDRLhW (ORCPT ); Mon, 18 Apr 2016 07:37:22 -0400 Received: from forward-corp1f.mail.yandex.net ([95.108.130.40]:59380 "EHLO forward-corp1f.mail.yandex.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751535AbcDRLhU (ORCPT ); Mon, 18 Apr 2016 07:37:20 -0400 Authentication-Results: smtpcorp1m.mail.yandex.net; dkim=pass header.i=@yandex-team.ru Subject: [PATCH] cls_cgroup: get sk_classid only from full sockets From: Konstantin Khlebnikov To: netdev@vger.kernel.org, "David S. Miller" Cc: cgroups@vger.kernel.org, linux-kernel@vger.kernel.org Date: Mon, 18 Apr 2016 14:37:10 +0300 Message-ID: <146097943086.15300.8997345346172526153.stgit@buzz> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org skb->sk could point to timewait or request socket which has no sk_classid. Detected as "BUG: KASAN: slab-out-of-bounds in cls_cgroup_classify". Signed-off-by: Konstantin Khlebnikov --- include/net/cls_cgroup.h | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/include/net/cls_cgroup.h b/include/net/cls_cgroup.h index c0a92e2c286d..74c9693d4941 100644 --- a/include/net/cls_cgroup.h +++ b/include/net/cls_cgroup.h @@ -17,6 +17,7 @@ #include #include #include +#include #ifdef CONFIG_CGROUP_NET_CLASSID struct cgroup_cls_state { @@ -63,11 +64,13 @@ static inline u32 task_get_classid(const struct sk_buff *skb) * softirqs always disables bh. */ if (in_serving_softirq()) { + struct sock *sk = skb_to_full_sk(skb); + /* If there is an sock_cgroup_classid we'll use that. */ - if (!skb->sk) + if (!sk || !sk_fullsock(sk)) return 0; - classid = sock_cgroup_classid(&skb->sk->sk_cgrp_data); + classid = sock_cgroup_classid(&sk->sk_cgrp_data); } return classid;