Commit 5142239a authored by Lorenzo Bianconi's avatar Lorenzo Bianconi Committed by Daniel Borkmann
Browse files

net: veth: Account total xdp_frame len running ndo_xdp_xmit 



Even if this is a theoretical issue since it is not possible to perform
XDP_REDIRECT on a non-linear xdp_frame, veth driver does not account
paged area in ndo_xdp_xmit function pointer.
Introduce xdp_get_frame_len utility routine to get the xdp_frame full
length and account total frame size running XDP_REDIRECT of a
non-linear xdp frame into a veth device.

Signed-off-by: default avatarLorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Acked-by: default avatarToke Hoiland-Jorgensen <toke@redhat.com>
Acked-by: default avatarJohn Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/54f9fd3bb65d190daf2c0bbae2f852ff16cfbaa0.1646989407.git.lorenzo@kernel.org
parent ad13baf4

drivers/net/veth.c

+2 −2
Original line number Diff line number Diff line
@@ -494,7 +494,7 @@ static int veth_xdp_xmit(struct net_device *dev, int n, 
		struct xdp_frame *frame = frames[i];

		void *ptr = veth_xdp_to_ptr(frame);



		if (unlikely(frame->len > max_len ||

		if (unlikely(xdp_get_frame_len(frame) > max_len ||

			     __ptr_ring_produce(&rq->xdp_ring, ptr)))

			break;

		nxmit++;
@@ -855,7 +855,7 @@ static int veth_xdp_rcv(struct veth_rq *rq, int budget, 
			/* ndo_xdp_xmit */

			struct xdp_frame *frame = veth_ptr_to_xdp(ptr);



			stats->xdp_bytes += frame->len;

			stats->xdp_bytes += xdp_get_frame_len(frame);

			frame = veth_xdp_rcv_one(rq, frame, bq, stats);

			if (frame) {

				/* XDP_PASS */

include/net/xdp.h

+14 −0
Original line number Diff line number Diff line
@@ -343,6 +343,20 @@ static inline void xdp_release_frame(struct xdp_frame *xdpf) 
	__xdp_release_frame(xdpf->data, mem);

}



static __always_inline unsigned int xdp_get_frame_len(struct xdp_frame *xdpf)

{

	struct skb_shared_info *sinfo;

	unsigned int len = xdpf->len;



	if (likely(!xdp_frame_has_frags(xdpf)))

		goto out;



	sinfo = xdp_get_shared_info_from_frame(xdpf);

	len += sinfo->xdp_frags_size;

out:

	return len;

}



int __xdp_rxq_info_reg(struct xdp_rxq_info *xdp_rxq,

		       struct net_device *dev, u32 queue_index,

		       unsigned int napi_id, u32 frag_size);