From: Jason Wang <jasowang@redhat.com>
Date: Tue, 22 May 2018 03:44:28 +0000 (+0800)
Subject: virtio-net: correctly redirect linearized packet
X-Git-Tag: v4.16.15~6
X-Git-Url: http://git.hungrycats.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ad9168674dc5b2ec77095cccd1c2fda04d084b51;p=linux

virtio-net: correctly redirect linearized packet

[ Upstream commit 6890418bbb780f0ee9cf124055afa79777f1b4f1 ]

After a linearized packet was redirected by XDP, we should not go for
the err path which will try to pop buffers for the next packet and
increase the drop counter. Fixing this by just drop the page refcnt
for the original page.

Fixes: 186b3c998c50 ("virtio-net: support XDP_REDIRECT")
Reported-by: David Ahern <dsahern@gmail.com>
Tested-by: David Ahern <dsahern@gmail.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 64e7a32098be..8911e3466e61 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -786,7 +786,7 @@ static struct sk_buff *receive_mergeable(struct net_device *dev,
 			}
 			*xdp_xmit = true;
 			if (unlikely(xdp_page != page))
-				goto err_xdp;
+				put_page(page);
 			rcu_read_unlock();
 			goto xdp_xmit;
 		default: