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 47C04C05027 for ; Thu, 9 Feb 2023 01:34:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231366AbjBIBeW (ORCPT ); Wed, 8 Feb 2023 20:34:22 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59296 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229911AbjBIBeU (ORCPT ); Wed, 8 Feb 2023 20:34:20 -0500 Received: from smtp-fw-80006.amazon.com (smtp-fw-80006.amazon.com [99.78.197.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 22E3221A29 for ; Wed, 8 Feb 2023 17:34:20 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1675906460; x=1707442460; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=F9V+IpLBdXpKunFdHkg28X7ZjkxBYgMLhpvTdEEYXf8=; b=cIGmegpe8wouIosdeFZB3NCMRAwjoI4jZLlm6URXoUXAfDi9Uhu5q0AI g+3R/oSzqfNrqu0cx7YW3bMjxjAG2Z9cQhpuoczHNmmYIoq4RVra1EglT uTK7RsTW3GFalkwhfbpGxQtzZ8cr/wLeAdEnnHLLTgEk21eZy2Beh1v3R c=; X-IronPort-AV: E=Sophos;i="5.97,281,1669075200"; d="scan'208";a="179932228" Received: from pdx4-co-svc-p1-lb2-vlan2.amazon.com (HELO email-inbound-relay-pdx-2c-m6i4x-e7094f15.us-west-2.amazon.com) ([10.25.36.210]) by smtp-border-fw-80006.pdx80.corp.amazon.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Feb 2023 01:34:18 +0000 Received: from EX13MTAUWB002.ant.amazon.com (pdx1-ws-svc-p6-lb9-vlan3.pdx.amazon.com [10.236.137.198]) by email-inbound-relay-pdx-2c-m6i4x-e7094f15.us-west-2.amazon.com (Postfix) with ESMTPS id EA719414F7; Thu, 9 Feb 2023 01:34:15 +0000 (UTC) Received: from EX19D004ANA001.ant.amazon.com (10.37.240.138) by EX13MTAUWB002.ant.amazon.com (10.43.161.202) with Microsoft SMTP Server (TLS) id 15.0.1497.45; Thu, 9 Feb 2023 01:34:15 +0000 Received: from 88665a182662.ant.amazon.com (10.43.161.198) by EX19D004ANA001.ant.amazon.com (10.37.240.138) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA) id 15.2.1118.24; Thu, 9 Feb 2023 01:34:12 +0000 From: Kuniyuki Iwashima To: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni CC: Kuniyuki Iwashima , Kuniyuki Iwashima , , Andrii , Arnaldo Carvalho de Melo Subject: [PATCH v2 net 1/2] dccp/tcp: Avoid negative sk_forward_alloc by ipv6_pinfo.pktoptions. Date: Wed, 8 Feb 2023 17:33:28 -0800 Message-ID: <20230209013329.87879-2-kuniyu@amazon.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20230209013329.87879-1-kuniyu@amazon.com> References: <20230209013329.87879-1-kuniyu@amazon.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-Originating-IP: [10.43.161.198] X-ClientProxiedBy: EX13D37UWC001.ant.amazon.com (10.43.162.33) To EX19D004ANA001.ant.amazon.com (10.37.240.138) Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Eric Dumazet pointed out [0] that when we call skb_set_owner_r() for ipv6_pinfo.pktoptions, sk_rmem_schedule() has not been called, resulting in a negative sk_forward_alloc. Note that in (dccp|tcp)_v6_do_rcv(), we call sk_rmem_schedule() just after skb_clone() instead of after ipv6_opt_accepted(). This is because tcp_send_synack() can make sk_forward_alloc negative before ipv6_opt_accepted() in the crossed SYN-ACK or self-connect() cases. [0]: https://lore.kernel.org/netdev/CANn89iK9oc20Jdi_41jb9URdF210r7d1Y-+uypbMSbOfY6jqrg@mail.gmail.com/ Fixes: 323fbd0edf3f ("net: dccp: Add handling of IPV6_PKTOPTIONS to dccp_v6_do_rcv()") Fixes: 3df80d9320bc ("[DCCP]: Introduce DCCPv6") Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima --- Cc: Andrii Cc: Arnaldo Carvalho de Melo --- net/dccp/ipv6.c | 23 +++++++++++++++++++---- net/ipv6/tcp_ipv6.c | 22 ++++++++++++++++++---- 2 files changed, 37 insertions(+), 8 deletions(-) diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c index 4260fe466993..2687e7ef5b5d 100644 --- a/net/dccp/ipv6.c +++ b/net/dccp/ipv6.c @@ -554,8 +554,15 @@ static struct sock *dccp_v6_request_recv_sock(const struct sock *sk, newnp->pktoptions = skb_clone(ireq->pktopts, GFP_ATOMIC); consume_skb(ireq->pktopts); ireq->pktopts = NULL; - if (newnp->pktoptions) - skb_set_owner_r(newnp->pktoptions, newsk); + if (newnp->pktoptions) { + if (sk_rmem_schedule(newsk, newnp->pktoptions, + newnp->pktoptions->truesize)) { + skb_set_owner_r(newnp->pktoptions, newsk); + } else { + __kfree_skb(newnp->pktoptions); + newnp->pktoptions = NULL; + } + } } return newsk; @@ -614,8 +621,17 @@ static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) by tcp. Feel free to propose better solution. --ANK (980728) */ - if (np->rxopt.all) + if (np->rxopt.all) { opt_skb = skb_clone(skb, GFP_ATOMIC); + if (opt_skb) { + if (sk_rmem_schedule(sk, opt_skb, opt_skb->truesize)) { + skb_set_owner_r(opt_skb, sk); + } else { + __kfree_skb(opt_skb); + opt_skb = NULL; + } + } + } if (sk->sk_state == DCCP_OPEN) { /* Fast path */ if (dccp_rcv_established(sk, skb, dccp_hdr(skb), skb->len)) @@ -679,7 +695,6 @@ static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) np->flow_label = ip6_flowlabel(ipv6_hdr(opt_skb)); if (ipv6_opt_accepted(sk, opt_skb, &DCCP_SKB_CB(opt_skb)->header.h6)) { - skb_set_owner_r(opt_skb, sk); memmove(IP6CB(opt_skb), &DCCP_SKB_CB(opt_skb)->header.h6, sizeof(struct inet6_skb_parm)); diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 11b736a76bd7..95c1078aba5a 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -1392,8 +1392,14 @@ static struct sock *tcp_v6_syn_recv_sock(const struct sock *sk, struct sk_buff * consume_skb(ireq->pktopts); ireq->pktopts = NULL; if (newnp->pktoptions) { - tcp_v6_restore_cb(newnp->pktoptions); - skb_set_owner_r(newnp->pktoptions, newsk); + if (sk_rmem_schedule(newsk, newnp->pktoptions, + newnp->pktoptions->truesize)) { + tcp_v6_restore_cb(newnp->pktoptions); + skb_set_owner_r(newnp->pktoptions, newsk); + } else { + __kfree_skb(newnp->pktoptions); + newnp->pktoptions = NULL; + } } } } else { @@ -1465,8 +1471,17 @@ int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) by tcp. Feel free to propose better solution. --ANK (980728) */ - if (np->rxopt.all) + if (np->rxopt.all) { opt_skb = skb_clone(skb, sk_gfp_mask(sk, GFP_ATOMIC)); + if (opt_skb) { + if (sk_rmem_schedule(sk, opt_skb, opt_skb->truesize)) { + skb_set_owner_r(opt_skb, sk); + } else { + __kfree_skb(opt_skb); + opt_skb = NULL; + } + } + } reason = SKB_DROP_REASON_NOT_SPECIFIED; if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */ @@ -1552,7 +1567,6 @@ int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) if (np->repflow) np->flow_label = ip6_flowlabel(ipv6_hdr(opt_skb)); if (ipv6_opt_accepted(sk, opt_skb, &TCP_SKB_CB(opt_skb)->header.h6)) { - skb_set_owner_r(opt_skb, sk); tcp_v6_restore_cb(opt_skb); opt_skb = xchg(&np->pktoptions, opt_skb); } else { -- 2.30.2