From patchwork Fri Apr 3 21:16:24 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexei Starovoitov X-Patchwork-Id: 458068 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 586211400B7 for ; Sat, 4 Apr 2015 08:16:37 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752318AbbDCVQd (ORCPT ); Fri, 3 Apr 2015 17:16:33 -0400 Received: from mail-pa0-f43.google.com ([209.85.220.43]:34292 "EHLO mail-pa0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752056AbbDCVQc (ORCPT ); Fri, 3 Apr 2015 17:16:32 -0400 Received: by pactp5 with SMTP id tp5so126930224pac.1 for ; Fri, 03 Apr 2015 14:16:31 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=jjAAEiK1PihcqWhrHq8dadLRtTSULhNARcifKVUignY=; b=bwNo308zh3f17LIBTC5jMNNAKk5wsdFMVoJW0S1HxCuxpL1qJXCNbKe2+WO+ILq/Xd dBRH/mPxWFPPNBwujviBs1Y1VeVf555jftxUBmijGu6bBh12uIeuEauqJPT/DggfBRAX bQxDDJFb+48fCCzQ6s03xY2e+T5YfyoaILI3StKshDFyoVp6OHE/qnRtjXRVOMEaKrIT CAFCC6Pzxk4dEGA6oXw62Iz/+Ho7r/vv4eOSVZ77TVvXEscIqXr2Chybbhh/krNHwYX7 lPBfjzINHQaA5R0bZrHx8VBZdAaUgxzACBBm0taiRUOcEnyDGcUU/6gKQcC7D2BE5yGo yy4g== X-Gm-Message-State: ALoCoQmNEfxczDqCaN0u9B5QnPgK7GC9lnNYaQqTcFh6tKyvXzYH17e8CMr9TY/ztQ9EmA0LPjyx X-Received: by 10.66.141.171 with SMTP id rp11mr6101778pab.44.1428095791533; Fri, 03 Apr 2015 14:16:31 -0700 (PDT) Received: from localhost.localdomain ([12.229.56.227]) by mx.google.com with ESMTPSA id oo3sm5716087pdb.26.2015.04.03.14.16.30 (version=TLSv1.1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 03 Apr 2015 14:16:30 -0700 (PDT) From: Alexei Starovoitov To: "David S. Miller" Cc: Daniel Borkmann , Jiri Pirko , Jamal Hadi Salim , linux-api@vger.kernel.org, netdev@vger.kernel.org Subject: [PATCH net-next] tc: cls_bpf: make ingress and egress qdiscs consistent Date: Fri, 3 Apr 2015 14:16:24 -0700 Message-Id: <1428095784-7091-1-git-send-email-ast@plumgrid.com> X-Mailer: git-send-email 1.7.9.5 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org BPF programs attached to ingress and egress qdiscs see inconsistent skb->data. For ingress L2 header is already pulled, whereas for egress it's present. That makes writing programs more difficult. Make them consistent by pushing L2 before running the programs and pulling it back afterwards. Similar approach is taken by skb_defer_rx_timestamp() which does push/pull before calling ptp_classify_raw()->BPF_PROG_RUN(). Signed-off-by: Alexei Starovoitov --- Looks like noone has tried bpf with ingress qdisc before, otherwise this problem would have been found sooner. This patch is probably not needed for 'net', since tc+bpf infra only starting to come alive. net/sched/cls_bpf.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/net/sched/cls_bpf.c b/net/sched/cls_bpf.c index 5c4171c5d2bd..b1cefd2037c9 100644 --- a/net/sched/cls_bpf.c +++ b/net/sched/cls_bpf.c @@ -66,6 +66,12 @@ static int cls_bpf_classify(struct sk_buff *skb, const struct tcf_proto *tp, struct cls_bpf_prog *prog; int ret = -1; + if (tp->q->flags & TCQ_F_INGRESS) { + if (skb_headroom(skb) < ETH_HLEN) + return -1; + __skb_push(skb, ETH_HLEN); + } + /* Needed here for accessing maps. */ rcu_read_lock(); list_for_each_entry_rcu(prog, &head->plist, link) { @@ -86,6 +92,9 @@ static int cls_bpf_classify(struct sk_buff *skb, const struct tcf_proto *tp, } rcu_read_unlock(); + if (tp->q->flags & TCQ_F_INGRESS) + __skb_pull(skb, ETH_HLEN); + return ret; }