From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.toke.dk (mail.toke.dk [IPv6:2001:470:dc45:1000::1]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 649F03BA8E for ; Tue, 11 Sep 2018 18:19:34 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=toke.dk; s=20161023; t=1536704373; bh=O4Y7eqIdEXaAty7Hnl2Yto4Gh8vwlVXVvbF9s15//Zs=; h=Subject:From:To:Cc:Date:From; b=HF6ElTHuD7XFKE9LJQkdz7GYkP0zxgPtnjtZTmqcQE/pbelK62SjK8UH1Fb83xgxf 3cS4L3lFOC0OKsuYHfEGU+5+IkFwjWskr1Cv4V/lixg2SNhdFkuf9Nf1mQmsRshDdo e5kziJNClQDwbRNmaPCrxH9zOx2seltV8TKMWKzBNhAO1pTDfe7Zw9HpWSc6RbSC/x 9nsifGr7xjZDc2bNtj/XSsI8EZqcXe8gGkWlJx4zuFutWIWPB0J7BxT3dPhXN4Mbdp lFCUWdQhSzils7ESZW4CJGpaL3no5BmgSlbgGWhp9k+f8qsrSMg2dNR6Hi6den4Z99 qV3+SgEJDuLRA== From: Toke =?utf-8?q?H=C3=B8iland-J=C3=B8rgensen?= To: netdev@vger.kernel.org Cc: cake@lists.bufferbloat.net, Eric Dumazet Date: Wed, 12 Sep 2018 00:19:32 +0200 X-Clacks-Overhead: GNU Terry Pratchett Message-ID: <153670437243.12756.693381878569982309.stgit@alrua-kau> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Subject: [Cake] [PATCH net] gso_segment: Reset skb->mac_len after modifying network header X-BeenThere: cake@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: Cake - FQ_codel the next generation List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 11 Sep 2018 22:19:34 -0000 When splitting a GSO segment that consists of encapsulated packets, the skb->mac_len of the segments can end up being set wrong, causing packet drops in particular when using act_mirred and ifb interfaces in combination with a qdisc that splits GSO packets. This happens because at the time skb_segment() is called, network_header will point to the inner header, throwing off the calculation in skb_reset_mac_len(). The network_header is subsequently adjust by the outer IP gso_segment handlers, but they don't set the mac_len. Fix this by adding skb_reset_mac_len() calls to both the IPv4 and IPv6 gso_segment handlers, after they modify the network_header. Signed-off-by: Toke Høiland-Jørgensen --- net/ipv4/af_inet.c | 1 + net/ipv6/ip6_offload.c | 1 + 2 files changed, 2 insertions(+) diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index 20fda8fb8ffd..1fbe2f815474 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -1377,6 +1377,7 @@ struct sk_buff *inet_gso_segment(struct sk_buff *skb, if (encap) skb_reset_inner_headers(skb); skb->network_header = (u8 *)iph - skb->head; + skb_reset_mac_len(skb); } while ((skb = skb->next)); out: diff --git a/net/ipv6/ip6_offload.c b/net/ipv6/ip6_offload.c index 37ff4805b20c..c7e495f12011 100644 --- a/net/ipv6/ip6_offload.c +++ b/net/ipv6/ip6_offload.c @@ -115,6 +115,7 @@ static struct sk_buff *ipv6_gso_segment(struct sk_buff *skb, payload_len = skb->len - nhoff - sizeof(*ipv6h); ipv6h->payload_len = htons(payload_len); skb->network_header = (u8 *)ipv6h - skb->head; + skb_reset_mac_len(skb); if (udpfrag) { int err = ip6_find_1stfragopt(skb, &prevhdr);