[PATCH net 4/4] virito-net: fix leaking page for gso packet during mergeable XDP
From: Jason Wang <hidden>
Date: 2018-05-21 08:35:06
Subsystem:
networking drivers, the rest, virtio net driver · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, "Michael S. Tsirkin", Jason Wang
Possibly related (same subject, not in this thread)
- 2018-05-22 · Re: [PATCH net 4/4] virito-net: fix leaking page for gso packet during mergeable XDP · Jason Wang <hidden>
- 2018-05-21 · Re: [PATCH net 4/4] virito-net: fix leaking page for gso packet during mergeable XDP · "Michael S. Tsirkin" <mst@redhat.com>
We need to drop refcnt to xdp_page if we see a gso packet. Otherwise
it will be leaked. Fixing this by moving the check of gso packet above
the linearizing logic.
Cc: John Fastabend <john.fastabend@gmail.com>
Fixes: 72979a6c3590 ("virtio_net: xdp, add slowpath case for non contiguous buffers")
Signed-off-by: Jason Wang <redacted>
---
drivers/net/virtio_net.c | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 165a922..f8db809 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c@@ -707,6 +707,14 @@ static struct sk_buff *receive_mergeable(struct net_device *dev, void *data; u32 act; + /* Transient failure which in theory could occur if + * in-flight packets from before XDP was enabled reach + * the receive path after XDP is loaded. In practice I + * was not able to create this condition. + */ + if (unlikely(hdr->hdr.gso_type)) + goto err_xdp; + /* This happens when rx buffer size is underestimated * or headroom is not enough because of the buffer * was refilled before XDP is set. This should only
@@ -728,14 +736,6 @@ static struct sk_buff *receive_mergeable(struct net_device *dev, xdp_page = page; } - /* Transient failure which in theory could occur if - * in-flight packets from before XDP was enabled reach - * the receive path after XDP is loaded. In practice I - * was not able to create this condition. - */ - if (unlikely(hdr->hdr.gso_type)) - goto err_xdp; - /* Allow consuming headroom but reserve enough space to push * the descriptor on if we get an XDP_TX return code. */
--
2.7.4