From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964945AbbCXREg (ORCPT ); Tue, 24 Mar 2015 13:04:36 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:33458 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964900AbbCXREX (ORCPT ); Tue, 24 Mar 2015 13:04:23 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jamal Hadi Salim , John Fastabend , Cong Wang , Eric Dumazet , "David S. Miller" Subject: [PATCH 3.19 006/123] net_sched: fix struct tc_u_hnode layout in u32 Date: Tue, 24 Mar 2015 16:45:15 +0100 Message-Id: <20150324154424.031798199@linuxfoundation.org> X-Mailer: git-send-email 2.3.3 In-Reply-To: <20150324154423.655554012@linuxfoundation.org> References: <20150324154423.655554012@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: WANG Cong [ Upstream commit 5778d39d070b4ac5f889928175b7f2d53ae7504e ] We dynamically allocate divisor+1 entries for ->ht[] in tc_u_hnode: ht = kzalloc(sizeof(*ht) + divisor*sizeof(void *), GFP_KERNEL); So ->ht is supposed to be the last field of this struct, however this is broken, since an rcu head is appended after it. Fixes: 1ce87720d456 ("net: sched: make cls_u32 lockless") Cc: Jamal Hadi Salim Cc: John Fastabend Signed-off-by: Cong Wang Acked-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/sched/cls_u32.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) --- a/net/sched/cls_u32.c +++ b/net/sched/cls_u32.c @@ -78,8 +78,11 @@ struct tc_u_hnode { struct tc_u_common *tp_c; int refcnt; unsigned int divisor; - struct tc_u_knode __rcu *ht[1]; struct rcu_head rcu; + /* The 'ht' field MUST be the last field in structure to allow for + * more entries allocated at end of structure. + */ + struct tc_u_knode __rcu *ht[1]; }; struct tc_u_common {