[PATCH v3 2/5] net: tun: don't assume IFF_VNET_HDR in tun_xdp_one() tx path
From: David Woodhouse <dwmw2@infradead.org>
Date: 2021-06-24 12:30:53
Subsystem:
networking drivers, the rest, tun/tap driver · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, Willem de Bruijn, Jason Wang
From: David Woodhouse <redacted>
Sometimes it's just a data packet. The virtio_net_hdr processing should be
conditional on IFF_VNET_HDR, just as it is in tun_get_user().
Fixes: 043d222f93ab ("tuntap: accept an array of XDP buffs through sendmsg()")
Signed-off-by: David Woodhouse <redacted>
---
drivers/net/tun.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 67b406fa0881..9acd448e6dfc 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c@@ -2331,7 +2331,7 @@ static int tun_xdp_one(struct tun_struct *tun, { unsigned int datasize = xdp->data_end - xdp->data; struct tun_xdp_hdr *hdr = xdp->data_hard_start; - struct virtio_net_hdr *gso = &hdr->gso; + struct virtio_net_hdr *gso = NULL; struct bpf_prog *xdp_prog; struct sk_buff *skb = NULL; u32 rxhash = 0, act;
@@ -2340,9 +2340,12 @@ static int tun_xdp_one(struct tun_struct *tun, bool skb_xdp = false; struct page *page; + if (tun->flags & IFF_VNET_HDR) + gso = &hdr->gso; + xdp_prog = rcu_dereference(tun->xdp_prog); if (xdp_prog) { - if (gso->gso_type) { + if (gso && gso->gso_type) { skb_xdp = true; goto build; }
@@ -2388,7 +2391,7 @@ static int tun_xdp_one(struct tun_struct *tun, skb_reserve(skb, xdp->data - xdp->data_hard_start); skb_put(skb, xdp->data_end - xdp->data); - if (virtio_net_hdr_to_skb(skb, gso, tun_is_little_endian(tun))) { + if (gso && virtio_net_hdr_to_skb(skb, gso, tun_is_little_endian(tun))) { atomic_long_inc(&tun->rx_frame_errors); kfree_skb(skb); err = -EINVAL;
--
2.31.1