virtio-net: fix pages leaking when building skb in big mode

We try to use build_skb() if we had sufficient tailroom. But we forget
to release the unused pages chained via private in big mode which will
leak pages. Fixing this by release the pages after building the skb in
big mode.

Cc: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Fixes: e5080fbc9738 ("virtio-net: page_to_skb() use build_skb when there's sufficient tailroom")
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 271d38c1d9f80673cf90cf2077461042a5f74179..79bd2585ec6b2d16d76280d189d775313ccfd530 100644 (file)
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -423,6 +423,10 @@ static struct sk_buff *page_to_skb(struct virtnet_info *vi,
 
                skb_reserve(skb, p - buf);
                skb_put(skb, len);
+
+               page = (struct page *)page->private;
+               if (page)
+                       give_pages(rq, page);
                goto ok;
        }