1 From 5142239a22219921a7863cf00c9ab853c00689d8 Mon Sep 17 00:00:00 2001
2 From: Lorenzo Bianconi <lorenzo@kernel.org>
3 Date: Fri, 11 Mar 2022 10:14:18 +0100
4 Subject: [PATCH] net: veth: Account total xdp_frame len running ndo_xdp_xmit
6 Even if this is a theoretical issue since it is not possible to perform
7 XDP_REDIRECT on a non-linear xdp_frame, veth driver does not account
8 paged area in ndo_xdp_xmit function pointer.
9 Introduce xdp_get_frame_len utility routine to get the xdp_frame full
10 length and account total frame size running XDP_REDIRECT of a
11 non-linear xdp frame into a veth device.
13 Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
14 Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
15 Acked-by: Toke Hoiland-Jorgensen <toke@redhat.com>
16 Acked-by: John Fastabend <john.fastabend@gmail.com>
17 Link: https://lore.kernel.org/bpf/54f9fd3bb65d190daf2c0bbae2f852ff16cfbaa0.1646989407.git.lorenzo@kernel.org
19 drivers/net/veth.c | 4 ++--
20 include/net/xdp.h | 14 ++++++++++++++
21 2 files changed, 16 insertions(+), 2 deletions(-)
23 diff --git a/drivers/net/veth.c b/drivers/net/veth.c
24 index 58b20ea171dd..b77ce3fdcfe8 100644
25 --- a/drivers/net/veth.c
26 +++ b/drivers/net/veth.c
27 @@ -501,7 +501,7 @@ static int veth_xdp_xmit(struct net_devi
28 struct xdp_frame *frame = frames[i];
29 void *ptr = veth_xdp_to_ptr(frame);
31 - if (unlikely(frame->len > max_len ||
32 + if (unlikely(xdp_get_frame_len(frame) > max_len ||
33 __ptr_ring_produce(&rq->xdp_ring, ptr)))
36 @@ -862,7 +862,7 @@ static int veth_xdp_rcv(struct veth_rq *
38 struct xdp_frame *frame = veth_ptr_to_xdp(ptr);
40 - stats->xdp_bytes += frame->len;
41 + stats->xdp_bytes += xdp_get_frame_len(frame);
42 frame = veth_xdp_rcv_one(rq, frame, bq, stats);
45 --- a/include/net/xdp.h
46 +++ b/include/net/xdp.h
47 @@ -295,6 +295,20 @@ out:
48 __xdp_release_frame(xdpf->data, mem);
51 +static __always_inline unsigned int xdp_get_frame_len(struct xdp_frame *xdpf)
53 + struct skb_shared_info *sinfo;
54 + unsigned int len = xdpf->len;
56 + if (likely(!xdp_frame_has_frags(xdpf)))
59 + sinfo = xdp_get_shared_info_from_frame(xdpf);
60 + len += sinfo->xdp_frags_size;
65 int xdp_rxq_info_reg(struct xdp_rxq_info *xdp_rxq,
66 struct net_device *dev, u32 queue_index, unsigned int napi_id);
67 void xdp_rxq_info_unreg(struct xdp_rxq_info *xdp_rxq);