XDP Newbie developer discussions
 help / color / mirror / Atom feed
From: Jakub Kicinski <jakub.kicinski@netronome.com>
To: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: netdev@vger.kernel.org, "David S. Miller" <davem@davemloft.net>,
	xdp-newbies@vger.kernel.org,
	Daniel Borkmann <borkmann@iogearbox.net>,
	brandon.cazander@multapplied.net,
	Alexei Starovoitov <alexei.starovoitov@gmail.com>
Subject: Re: [net v1 PATCH 4/4] net: fix bpf_xdp_adjust_head regression for generic-XDP
Date: Thu, 1 Aug 2019 17:44:06 -0700	[thread overview]
Message-ID: <20190801174406.0b554bb9@cakuba.netronome.com> (raw)
In-Reply-To: <156468243184.27559.7002090473019021952.stgit@firesoul>

On Thu, 01 Aug 2019 20:00:31 +0200, Jesper Dangaard Brouer wrote:
> When generic-XDP was moved to a later processing step by commit
> 458bf2f224f0 ("net: core: support XDP generic on stacked devices.")
> a regression was introduced when using bpf_xdp_adjust_head.
> 
> The issue is that after this commit the skb->network_header is now
> changed prior to calling generic XDP and not after. Thus, if the header
> is changed by XDP (via bpf_xdp_adjust_head), then skb->network_header
> also need to be updated again.  Fix by calling skb_reset_network_header().
> 
> Fixes: 458bf2f224f0 ("net: core: support XDP generic on stacked devices.")
> Reported-by: Brandon Cazander <brandon.cazander@multapplied.net>
> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>

Out of curiosity what was your conclusion regarding resetting the
transport header as well?

  reply	other threads:[~2019-08-02  0:44 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-07-31 21:12 xdpgeneric, XDP_PASS, and bpf_xdp_adjust_head decapsulation dropping packets Brandon Cazander
2019-08-01  8:18 ` Jesper Dangaard Brouer
2019-08-01 14:54   ` Jesper Dangaard Brouer
2019-08-01 16:05     ` Jesper Dangaard Brouer
2019-08-01 17:33   ` Brandon Cazander
2019-08-01 18:16     ` Jesper Dangaard Brouer
2019-08-01 18:53       ` Brandon Cazander
2019-08-01 18:00 ` [net v1 PATCH 0/4] net: fix regressions for generic-XDP Jesper Dangaard Brouer
2019-08-01 18:00   ` [net v1 PATCH 1/4] bpf: fix XDP vlan selftests test_xdp_vlan.sh Jesper Dangaard Brouer
2019-08-01 18:00   ` [net v1 PATCH 2/4] selftests/bpf: add wrapper scripts for test_xdp_vlan.sh Jesper Dangaard Brouer
2019-08-01 18:00   ` [net v1 PATCH 3/4] selftests/bpf: reduce time to execute test_xdp_vlan.sh Jesper Dangaard Brouer
2019-08-01 18:00   ` [net v1 PATCH 4/4] net: fix bpf_xdp_adjust_head regression for generic-XDP Jesper Dangaard Brouer
2019-08-02  0:44     ` Jakub Kicinski [this message]
2019-08-02  7:53       ` Jesper Dangaard Brouer
2019-08-02 17:08         ` Jakub Kicinski
2019-08-05 18:19   ` [net v1 PATCH 0/4] net: fix regressions " David Miller

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20190801174406.0b554bb9@cakuba.netronome.com \
    --to=jakub.kicinski@netronome.com \
    --cc=alexei.starovoitov@gmail.com \
    --cc=borkmann@iogearbox.net \
    --cc=brandon.cazander@multapplied.net \
    --cc=brouer@redhat.com \
    --cc=davem@davemloft.net \
    --cc=netdev@vger.kernel.org \
    --cc=xdp-newbies@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox