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 31932C433FE for ; Fri, 26 Nov 2021 15:27:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1378024AbhKZPaV (ORCPT ); Fri, 26 Nov 2021 10:30:21 -0500 Received: from mga04.intel.com ([192.55.52.120]:57026 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1350039AbhKZP2U (ORCPT ); Fri, 26 Nov 2021 10:28:20 -0500 X-IronPort-AV: E=McAfee;i="6200,9189,10180"; a="234409781" X-IronPort-AV: E=Sophos;i="5.87,266,1631602800"; d="scan'208";a="234409781" Received: from orsmga007.jf.intel.com ([10.7.209.58]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Nov 2021 07:25:07 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.87,266,1631602800"; d="scan'208";a="498435813" Received: from boxer.igk.intel.com (HELO boxer) ([10.102.20.173]) by orsmga007.jf.intel.com with ESMTP; 26 Nov 2021 07:25:05 -0800 Date: Fri, 26 Nov 2021 16:25:04 +0100 From: Maciej Fijalkowski To: Jesper Dangaard Brouer Cc: netdev@vger.kernel.org, intel-wired-lan@lists.osuosl.org, bjorn@kernel.org, Jakub Kicinski , bpf@vger.kernel.org, Daniel Borkmann , "David S. Miller" , magnus.karlsson@intel.com Subject: Re: [Intel-wired-lan] [PATCH net-next 1/2] igc: AF_XDP zero-copy metadata adjust breaks SKBs on XDP_PASS Message-ID: References: <163700856423.565980.10162564921347693758.stgit@firesoul> <163700858579.565980.15265721798644582439.stgit@firesoul> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <163700858579.565980.15265721798644582439.stgit@firesoul> Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Mon, Nov 15, 2021 at 09:36:25PM +0100, Jesper Dangaard Brouer wrote: > Driver already implicitly supports XDP metadata access in AF_XDP > zero-copy mode, as xsk_buff_pool's xp_alloc() naturally set xdp_buff > data_meta equal data. > > This works fine for XDP and AF_XDP, but if a BPF-prog adjust via > bpf_xdp_adjust_meta() and choose to call XDP_PASS, then igc function > igc_construct_skb_zc() will construct an invalid SKB packet. The > function correctly include the xdp->data_meta area in the memcpy, but > forgot to pull header to take metasize into account. > > Fixes: fc9df2a0b520 ("igc: Enable RX via AF_XDP zero-copy") > Signed-off-by: Jesper Dangaard Brouer Acked-by: Maciej Fijalkowski Great catch. Will take a look at other ZC enabled Intel drivers if they are affected as well. Thanks! > --- > drivers/net/ethernet/intel/igc/igc_main.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c > index 8e448288ee26..76b0a7311369 100644 > --- a/drivers/net/ethernet/intel/igc/igc_main.c > +++ b/drivers/net/ethernet/intel/igc/igc_main.c > @@ -2448,8 +2448,10 @@ static struct sk_buff *igc_construct_skb_zc(struct igc_ring *ring, > > skb_reserve(skb, xdp->data_meta - xdp->data_hard_start); > memcpy(__skb_put(skb, totalsize), xdp->data_meta, totalsize); > - if (metasize) > + if (metasize) { > skb_metadata_set(skb, metasize); > + __skb_pull(skb, metasize); > + } > > return skb; > } > > > _______________________________________________ > Intel-wired-lan mailing list > Intel-wired-lan@osuosl.org > https://lists.osuosl.org/mailman/listinfo/intel-wired-lan