From mboxrd@z Thu Jan 1 00:00:00 1970 From: Willem de Bruijn Subject: [PATCH net-next 3/3] ipv6: on reassembly, record frag_max_size Date: Wed, 2 Nov 2016 11:02:18 -0400 Message-ID: <1478098938-124108-4-git-send-email-willemdebruijn.kernel@gmail.com> References: <1478098938-124108-1-git-send-email-willemdebruijn.kernel@gmail.com> Cc: jdorfman@google.com, eric.dumazet@gmail.com, davem@davemloft.net, Willem de Bruijn To: netdev@vger.kernel.org Return-path: Received: from mail-qk0-f193.google.com ([209.85.220.193]:33926 "EHLO mail-qk0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755430AbcKBPC3 (ORCPT ); Wed, 2 Nov 2016 11:02:29 -0400 Received: by mail-qk0-f193.google.com with SMTP id o68so1407610qkf.1 for ; Wed, 02 Nov 2016 08:02:28 -0700 (PDT) In-Reply-To: <1478098938-124108-1-git-send-email-willemdebruijn.kernel@gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Willem de Bruijn IP6CB and IPCB have a frag_max_size field. In IPv6 this field is filled in when packets are reassembled by the connection tracking code. Also fill in when reassembling in the input path, to expose it through cmsg IPV6_RECVFRAGSIZE in all cases. Signed-off-by: Willem de Bruijn --- net/ipv6/reassembly.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/net/ipv6/reassembly.c b/net/ipv6/reassembly.c index 3815e85..e1da5b8 100644 --- a/net/ipv6/reassembly.c +++ b/net/ipv6/reassembly.c @@ -211,7 +211,7 @@ static int ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb, { struct sk_buff *prev, *next; struct net_device *dev; - int offset, end; + int offset, end, fragsize; struct net *net = dev_net(skb_dst(skb)->dev); u8 ecn; @@ -336,6 +336,10 @@ static int ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb, fq->ecn |= ecn; add_frag_mem_limit(fq->q.net, skb->truesize); + fragsize = -skb_network_offset(skb) + skb->len; + if (fragsize > fq->q.max_size) + fq->q.max_size = fragsize; + /* The first fragment. * nhoffset is obtained from the first fragment, of course. */ @@ -495,6 +499,7 @@ static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff *prev, ipv6_change_dsfield(ipv6_hdr(head), 0xff, ecn); IP6CB(head)->nhoff = nhoff; IP6CB(head)->flags |= IP6SKB_FRAGMENTED; + IP6CB(head)->frag_max_size = fq->q.max_size; /* Yes, and fold redundant checksum back. 8) */ skb_postpush_rcsum(head, skb_network_header(head), -- 2.8.0.rc3.226.g39d4020