From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:52294 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752783AbdLRNz0 (ORCPT ); Mon, 18 Dec 2017 08:55:26 -0500 Subject: Patch "netfilter: bridge: honor frag_max_size when refragmenting" has been added to the 4.4-stable tree To: fw@strlen.de, alexander.levin@verizon.com, gregkh@linuxfoundation.org, pablo@netfilter.org Cc: , From: Date: Mon, 18 Dec 2017 14:54:33 +0100 Message-ID: <1513605273165220@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled netfilter: bridge: honor frag_max_size when refragmenting to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: netfilter-bridge-honor-frag_max_size-when-refragmenting.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From foo@baz Mon Dec 18 14:47:43 CET 2017 From: Florian Westphal Date: Thu, 9 Mar 2017 23:22:30 +0100 Subject: netfilter: bridge: honor frag_max_size when refragmenting From: Florian Westphal [ Upstream commit 4ca60d08cbe65f501baad64af50fceba79c19fbb ] consider a bridge with mtu 9000, but end host sending smaller packets to another host with mtu < 9000. In this case, after reassembly, bridge+defrag would refragment, and then attempt to send the reassembled packet as long as it was below 9k. Instead we have to cap by the largest fragment size seen. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- net/bridge/br_netfilter_hooks.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) --- a/net/bridge/br_netfilter_hooks.c +++ b/net/bridge/br_netfilter_hooks.c @@ -701,18 +701,20 @@ static unsigned int nf_bridge_mtu_reduct static int br_nf_dev_queue_xmit(struct net *net, struct sock *sk, struct sk_buff *skb) { - struct nf_bridge_info *nf_bridge; - unsigned int mtu_reserved; + struct nf_bridge_info *nf_bridge = nf_bridge_info_get(skb); + unsigned int mtu, mtu_reserved; mtu_reserved = nf_bridge_mtu_reduction(skb); + mtu = skb->dev->mtu; - if (skb_is_gso(skb) || skb->len + mtu_reserved <= skb->dev->mtu) { + if (nf_bridge->frag_max_size && nf_bridge->frag_max_size < mtu) + mtu = nf_bridge->frag_max_size; + + if (skb_is_gso(skb) || skb->len + mtu_reserved <= mtu) { nf_bridge_info_free(skb); return br_dev_queue_push_xmit(net, sk, skb); } - nf_bridge = nf_bridge_info_get(skb); - /* This is wrong! We should preserve the original fragment * boundaries by preserving frag_list rather than refragmenting. */ Patches currently in stable-queue which might be from fw@strlen.de are queue-4.4/netfilter-bridge-honor-frag_max_size-when-refragmenting.patch