From patchwork Tue Jul 13 20:58:42 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vasily Averin X-Patchwork-Id: 12375047 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0682EC07E95 for ; Tue, 13 Jul 2021 20:58:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E4F1A61152 for ; Tue, 13 Jul 2021 20:58:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236098AbhGMVBg (ORCPT ); Tue, 13 Jul 2021 17:01:36 -0400 Received: from relay.sw.ru ([185.231.240.75]:56872 "EHLO relay.sw.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235060AbhGMVBf (ORCPT ); Tue, 13 Jul 2021 17:01:35 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=virtuozzo.com; s=relay; h=Content-Type:MIME-Version:Date:Message-ID:Subject :From; bh=Zrmp38HLQSSBOIHCzrhOGN2I10/GGB7t9iYmdElr2i4=; b=oMb4Zx3XkPrKaEbUyM5 Wje5X6G4fTPCuW8lq2suLGXW4TgOCp3OBmHH00y2+c8S2v3SusR25Qn+9XuCa5+lRKj94uTuhRNP/ iXlyHbEjI3G1wn0S0pYAjM0i8kU7eYZurzXkFfp9sddH2FQI/V2+x06yB+T2hZ8RISMH1qTvwjw=; Received: from [10.93.0.56] by relay.sw.ru with esmtp (Exim 4.94.2) (envelope-from ) id 1m3PUJ-003san-IH; Tue, 13 Jul 2021 23:58:43 +0300 From: Vasily Averin Subject: [PATCH NET v2 7/7] bpf: use skb_expand_head in bpf_out_neigh_v4/6 To: "David S. Miller" , Hideaki YOSHIFUJI , David Ahern , Jakub Kicinski , Eric Dumazet Cc: netdev@vger.kernel.org, Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , KP Singh , bpf@vger.kernel.org, linux-kernel@vger.kernel.org References: <55c9e2ae-b060-baa2-460c-90eb3e9ded5c@virtuozzo.com> Message-ID: <47012e92-9978-cab1-68e4-9565ebe96994@virtuozzo.com> Date: Tue, 13 Jul 2021 23:58:42 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org Unlike skb_realloc_headroom, new helper skb_expand_head does not allocate a new skb if possible. Additionally this patch replaces commonly used dereferencing with variables. Signed-off-by: Vasily Averin --- net/core/filter.c | 27 +++++---------------------- 1 file changed, 5 insertions(+), 22 deletions(-) diff --git a/net/core/filter.c b/net/core/filter.c index 65ab4e2..25a6950 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -2179,17 +2179,9 @@ static int bpf_out_neigh_v6(struct net *net, struct sk_buff *skb, skb->tstamp = 0; if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) { - struct sk_buff *skb2; - - skb2 = skb_realloc_headroom(skb, hh_len); - if (unlikely(!skb2)) { - kfree_skb(skb); + skb = skb_expand_head(skb, hh_len); + if (!skb) return -ENOMEM; - } - if (skb->sk) - skb_set_owner_w(skb2, skb->sk); - consume_skb(skb); - skb = skb2; } rcu_read_lock_bh(); @@ -2213,8 +2205,7 @@ static int bpf_out_neigh_v6(struct net *net, struct sk_buff *skb, } rcu_read_unlock_bh(); if (dst) - IP6_INC_STATS(dev_net(dst->dev), - ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES); + IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES); out_drop: kfree_skb(skb); return -ENETDOWN; @@ -2286,17 +2277,9 @@ static int bpf_out_neigh_v4(struct net *net, struct sk_buff *skb, skb->tstamp = 0; if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) { - struct sk_buff *skb2; - - skb2 = skb_realloc_headroom(skb, hh_len); - if (unlikely(!skb2)) { - kfree_skb(skb); + skb = skb_expand_head(skb, hh_len); + if (!skb) return -ENOMEM; - } - if (skb->sk) - skb_set_owner_w(skb2, skb->sk); - consume_skb(skb); - skb = skb2; } rcu_read_lock_bh();