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 26AA1C636D6 for ; Fri, 10 Feb 2023 00:22:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229881AbjBJAWp (ORCPT ); Thu, 9 Feb 2023 19:22:45 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48396 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229518AbjBJAWo (ORCPT ); Thu, 9 Feb 2023 19:22:44 -0500 Received: from smtp-fw-6001.amazon.com (smtp-fw-6001.amazon.com [52.95.48.154]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5A6C35FE5F for ; Thu, 9 Feb 2023 16:22:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1675988564; x=1707524564; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=Y60shk4m74PZQTdTIbDPOSADnNuZpjEfERsvgHgFlWo=; b=hklUTmuUc6Xue2Cp1bdzkD+gnWWBg7KpgiA4v2AtglmRlF4F6BCoOoCN Ta4kdhU2nFir4BOnajpEgS2Ef92/ZZS4ufiYFy+GgSJKR5L/7jBlgLTDe wTnBdeOYqmkoGNAVCICqnOcs5VyR0Vi5P/gfE5m7QHQjFOuU5cWA/ltMa k=; X-IronPort-AV: E=Sophos;i="5.97,285,1669075200"; d="scan'208";a="297234904" Received: from iad12-co-svc-p1-lb1-vlan2.amazon.com (HELO email-inbound-relay-pdx-2b-m6i4x-32fb4f1a.us-west-2.amazon.com) ([10.43.8.2]) by smtp-border-fw-6001.iad6.amazon.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Feb 2023 00:22:42 +0000 Received: from EX13MTAUWB001.ant.amazon.com (pdx1-ws-svc-p6-lb9-vlan2.pdx.amazon.com [10.236.137.194]) by email-inbound-relay-pdx-2b-m6i4x-32fb4f1a.us-west-2.amazon.com (Postfix) with ESMTPS id D22C4C3036; Fri, 10 Feb 2023 00:22:40 +0000 (UTC) Received: from EX19D004ANA001.ant.amazon.com (10.37.240.138) by EX13MTAUWB001.ant.amazon.com (10.43.161.249) with Microsoft SMTP Server (TLS) id 15.0.1497.45; Fri, 10 Feb 2023 00:22:39 +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; Fri, 10 Feb 2023 00:22:37 +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 v3 net 1/2] dccp/tcp: Avoid negative sk_forward_alloc by ipv6_pinfo.pktoptions. Date: Thu, 9 Feb 2023 16:22:01 -0800 Message-ID: <20230210002202.81442-2-kuniyu@amazon.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20230210002202.81442-1-kuniyu@amazon.com> References: <20230210002202.81442-1-kuniyu@amazon.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-Originating-IP: [10.43.161.198] X-ClientProxiedBy: EX13D37UWC003.ant.amazon.com (10.43.162.183) 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. We add a new helper which clones a skb and sets its owner only when sk_rmem_schedule() succeeds. Note that we move skb_set_owner_r() forward in (dccp|tcp)_v6_do_rcv() 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 --- include/net/sock.h | 13 +++++++++++++ net/dccp/ipv6.c | 7 ++----- net/ipv6/tcp_ipv6.c | 10 +++------- 3 files changed, 18 insertions(+), 12 deletions(-) diff --git a/include/net/sock.h b/include/net/sock.h index dcd72e6285b2..556209727633 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -2434,6 +2434,19 @@ static inline __must_check bool skb_set_owner_sk_safe(struct sk_buff *skb, struc return false; } +static inline struct sk_buff *skb_clone_and_charge_r(struct sk_buff *skb, struct sock *sk) +{ + skb = skb_clone(skb, sk_gfp_mask(sk, GFP_ATOMIC)); + if (skb) { + if (sk_rmem_schedule(sk, skb, skb->truesize)) { + skb_set_owner_r(skb, sk); + return skb; + } + __kfree_skb(skb); + } + return NULL; +} + static inline void skb_prepare_for_gro(struct sk_buff *skb) { if (skb->destructor != sock_wfree) { diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c index 4260fe466993..b9d7c3dd1cb3 100644 --- a/net/dccp/ipv6.c +++ b/net/dccp/ipv6.c @@ -551,11 +551,9 @@ static struct sock *dccp_v6_request_recv_sock(const struct sock *sk, *own_req = inet_ehash_nolisten(newsk, req_to_sk(req_unhash), NULL); /* Clone pktoptions received with SYN, if we own the req */ if (*own_req && ireq->pktopts) { - newnp->pktoptions = skb_clone(ireq->pktopts, GFP_ATOMIC); + newnp->pktoptions = skb_clone_and_charge_r(ireq->pktopts, newsk); consume_skb(ireq->pktopts); ireq->pktopts = NULL; - if (newnp->pktoptions) - skb_set_owner_r(newnp->pktoptions, newsk); } return newsk; @@ -615,7 +613,7 @@ static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) --ANK (980728) */ if (np->rxopt.all) - opt_skb = skb_clone(skb, GFP_ATOMIC); + opt_skb = skb_clone_and_charge_r(skb, sk); if (sk->sk_state == DCCP_OPEN) { /* Fast path */ if (dccp_rcv_established(sk, skb, dccp_hdr(skb), skb->len)) @@ -679,7 +677,6 @@ 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..b681644547d0 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -1387,14 +1387,11 @@ static struct sock *tcp_v6_syn_recv_sock(const struct sock *sk, struct sk_buff * /* Clone pktoptions received with SYN, if we own the req */ if (ireq->pktopts) { - newnp->pktoptions = skb_clone(ireq->pktopts, - sk_gfp_mask(sk, GFP_ATOMIC)); + newnp->pktoptions = skb_clone_and_charge_r(ireq->pktopts, newsk); consume_skb(ireq->pktopts); ireq->pktopts = NULL; - if (newnp->pktoptions) { + if (newnp->pktoptions) tcp_v6_restore_cb(newnp->pktoptions); - skb_set_owner_r(newnp->pktoptions, newsk); - } } } else { if (!req_unhash && found_dup_sk) { @@ -1466,7 +1463,7 @@ int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) --ANK (980728) */ if (np->rxopt.all) - opt_skb = skb_clone(skb, sk_gfp_mask(sk, GFP_ATOMIC)); + opt_skb = skb_clone_and_charge_r(skb, sk); reason = SKB_DROP_REASON_NOT_SPECIFIED; if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */ @@ -1552,7 +1549,6 @@ 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