From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 236C5C433F5 for ; Fri, 11 Feb 2022 07:13:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347600AbiBKHNL (ORCPT ); Fri, 11 Feb 2022 02:13:11 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:36416 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347598AbiBKHNJ (ORCPT ); Fri, 11 Feb 2022 02:13:09 -0500 Received: from mx0b-00082601.pphosted.com (mx0b-00082601.pphosted.com [67.231.153.30]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 808F11111 for ; Thu, 10 Feb 2022 23:13:06 -0800 (PST) Received: from pps.filterd (m0109332.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.1.2/8.16.1.2) with ESMTP id 21ANrI5h013553 for ; Thu, 10 Feb 2022 23:13:05 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : content-type : content-transfer-encoding : mime-version; s=facebook; bh=NkytTpRrUG56ut/EYoku5/SNA6tMzAT7dNYLvc4tjn0=; b=cPcXD175TTVNoUBzfADiQ2vHrsqNZMuVYDE4p5KM4JHQh176hNnLm9MQZy9t3VtDqhU2 0KBxdbRYpySazcM3J7qydycJQznyK/uV2cU3X/4qjJbRes6GsolVTZK3oV+PrejO8cUD 0wltAGiLIhJLKwFD2LrwBfROGDwlMwimIvo= Received: from mail.thefacebook.com ([163.114.132.120]) by mx0a-00082601.pphosted.com (PPS) with ESMTPS id 3e58e1kxj6-2 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Thu, 10 Feb 2022 23:13:05 -0800 Received: from twshared12416.02.ash9.facebook.com (2620:10d:c085:108::4) by mail.thefacebook.com (2620:10d:c085:21d::4) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Thu, 10 Feb 2022 23:13:04 -0800 Received: by devbig005.ftw2.facebook.com (Postfix, from userid 6611) id 7575D6C75963; Thu, 10 Feb 2022 23:12:57 -0800 (PST) From: Martin KaFai Lau To: , CC: Alexei Starovoitov , Andrii Nakryiko , Daniel Borkmann , David Miller , Eric Dumazet , Jakub Kicinski , , Willem de Bruijn Subject: [PATCH v4 net-next 4/8] net: Postpone skb_clear_delivery_time() until knowing the skb is delivered locally Date: Thu, 10 Feb 2022 23:12:57 -0800 Message-ID: <20220211071257.888905-1-kafai@fb.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220211071232.885225-1-kafai@fb.com> References: <20220211071232.885225-1-kafai@fb.com> X-FB-Internal: Safe Content-Type: text/plain X-Proofpoint-GUID: -jRb_ll-KXHlM7IFSwR-Si_ynJjtXLLH X-Proofpoint-ORIG-GUID: -jRb_ll-KXHlM7IFSwR-Si_ynJjtXLLH Content-Transfer-Encoding: quoted-printable X-Proofpoint-UnRewURL: 0 URL was un-rewritten MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.816,Hydra:6.0.425,FMLib:17.11.62.513 definitions=2022-02-11_02,2022-02-09_01,2021-12-02_01 X-Proofpoint-Spam-Details: rule=fb_outbound_notspam policy=fb_outbound score=0 phishscore=0 malwarescore=0 clxscore=1015 bulkscore=0 mlxlogscore=999 impostorscore=0 mlxscore=0 lowpriorityscore=0 adultscore=0 suspectscore=0 priorityscore=1501 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2201110000 definitions=main-2202110039 X-FB-Internal: deliver Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org This patch postpones the delivery_time clearing until the stack knows the skb is being delivered locally. That will allow other kernel forwarding path (e.g. ip[6]_forward) to keep the delivery_time also. An earlier attempt was to do skb_clear_delivery_time() in ip_local_deliver() and ip6_input(). The discussion [0] requested to move it one step later into ip_local_deliver_finish() and ip6_input_finish() so that the delivery_time can be kept for the ip_vs forwarding path also. To do that, this patch also needs to take care of the (rcv) timestamp usecase in ip_is_fragment(). It needs to expect delivery_time in the skb->tstamp, so it needs to save the mono_delivery_time bit in inet_frag_queue such that the delivery_time (if any) can be restored in the final defragmented skb. The ipv6 defrag is done in ip6_protocol_deliver_rcu() when figuring out how to handle nexthdr and IPPROTO_FRAGMENT (44) is one of the ipv6 extension header. ip6_protocol_deliver_rcu() is after ip6_input_finish() where the skb_clear_delivery_time() has already been done, so change is not needed. [0]: https://lore.kernel.org/netdev/ca728d81-80e8-3767-d5e-d44f6ad96e43@ssi= .bg/ Signed-off-by: Martin KaFai Lau --- include/net/inet_frag.h | 1 + net/core/dev.c | 1 - net/ipv4/inet_fragment.c | 1 + net/ipv4/ip_fragment.c | 1 + net/ipv4/ip_input.c | 1 + net/ipv6/ip6_input.c | 1 + 6 files changed, 5 insertions(+), 1 deletion(-) diff --git a/include/net/inet_frag.h b/include/net/inet_frag.h index 63540be0fc34..c0e517f31d82 100644 --- a/include/net/inet_frag.h +++ b/include/net/inet_frag.h @@ -90,6 +90,7 @@ struct inet_frag_queue { ktime_t stamp; int len; int meat; + bool mono_delivery_time; __u8 flags; u16 max_size; struct fqdir *fqdir; diff --git a/net/core/dev.c b/net/core/dev.c index f41707ab2fb9..041cef7473fd 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -5222,7 +5222,6 @@ static int __netif_receive_skb_core(struct sk_buff **= pskb, bool pfmemalloc, goto out; } #endif - skb_clear_delivery_time(skb); skb_reset_redirect(skb); skip_classify: if (pfmemalloc && !skb_pfmemalloc_protocol(skb)) diff --git a/net/ipv4/inet_fragment.c b/net/ipv4/inet_fragment.c index 341096807100..63948f6aeca0 100644 --- a/net/ipv4/inet_fragment.c +++ b/net/ipv4/inet_fragment.c @@ -572,6 +572,7 @@ void inet_frag_reasm_finish(struct inet_frag_queue *q, = struct sk_buff *head, skb_mark_not_on_list(head); head->prev =3D NULL; head->tstamp =3D q->stamp; + head->mono_delivery_time =3D q->mono_delivery_time; } EXPORT_SYMBOL(inet_frag_reasm_finish); =20 diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c index fad803d2d711..fb153569889e 100644 --- a/net/ipv4/ip_fragment.c +++ b/net/ipv4/ip_fragment.c @@ -349,6 +349,7 @@ static int ip_frag_queue(struct ipq *qp, struct sk_buff= *skb) qp->iif =3D dev->ifindex; =20 qp->q.stamp =3D skb->tstamp; + qp->q.mono_delivery_time =3D skb->mono_delivery_time; qp->q.meat +=3D skb->len; qp->ecn |=3D ecn; add_frag_mem_limit(qp->q.fqdir, skb->truesize); diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c index d94f9f7e60c3..95f7bb052784 100644 --- a/net/ipv4/ip_input.c +++ b/net/ipv4/ip_input.c @@ -226,6 +226,7 @@ void ip_protocol_deliver_rcu(struct net *net, struct sk= _buff *skb, int protocol) =20 static int ip_local_deliver_finish(struct net *net, struct sock *sk, struc= t sk_buff *skb) { + skb_clear_delivery_time(skb); __skb_pull(skb, skb_network_header_len(skb)); =20 rcu_read_lock(); diff --git a/net/ipv6/ip6_input.c b/net/ipv6/ip6_input.c index d4b1e2c5aa76..5b5ea35635f9 100644 --- a/net/ipv6/ip6_input.c +++ b/net/ipv6/ip6_input.c @@ -459,6 +459,7 @@ void ip6_protocol_deliver_rcu(struct net *net, struct s= k_buff *skb, int nexthdr, =20 static int ip6_input_finish(struct net *net, struct sock *sk, struct sk_bu= ff *skb) { + skb_clear_delivery_time(skb); rcu_read_lock(); ip6_protocol_deliver_rcu(net, skb, 0, false); rcu_read_unlock(); --=20 2.30.2