6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Marco Pinna <marco.pinn95@xxxxxxxxx>
commit b32a09ea7c38849ff925489a6bf5bd8914bc45df upstream.
Commit 82dfb540aeb2 ("VSOCK: Add virtio vsock vsockmon hooks") added
virtio_transport_deliver_tap_pkt() for handing packets to the
vsockmon device. However, in virtio_transport_send_pkt_work(),
the function is called before actually sending the packet (i.e.
before placing it in the virtqueue with virtqueue_add_sgs() and checking
whether it returned successfully).
Queuing the packet in the virtqueue can fail even multiple times.
However, in virtio_transport_deliver_tap_pkt() we deliver the packet
to the monitoring tap interface only the first time we call it.
This certainly avoids seeing the same packet replicated multiple times
in the monitoring interface, but it can show the packet sent with the
wrong timestamp or even before we succeed to queue it in the virtqueue.
Move virtio_transport_deliver_tap_pkt() after calling virtqueue_add_sgs()
and making sure it returned successfully.
Fixes: 82dfb540aeb2 ("VSOCK: Add virtio vsock vsockmon hooks")
Cc: stable@xxxxxxxxxxxxxx
Signed-off-by: Marco Pinna <marco.pinn95@xxxxxxxxx>
Reviewed-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20240329161259.411751-1-marco.pinn95@xxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/vmw_vsock/virtio_transport.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/net/vmw_vsock/virtio_transport.c
+++ b/net/vmw_vsock/virtio_transport.c
@@ -109,7 +109,6 @@ virtio_transport_send_pkt_work(struct wo
if (!skb)
break;
- virtio_transport_deliver_tap_pkt(skb);
reply = virtio_vsock_skb_reply(skb);
sg_init_one(&hdr, virtio_vsock_hdr(skb), sizeof(*virtio_vsock_hdr(skb)));
@@ -128,6 +127,8 @@ virtio_transport_send_pkt_work(struct wo
break;
}
+ virtio_transport_deliver_tap_pkt(skb);
+
if (reply) {
struct virtqueue *rx_vq = vsock->vqs[VSOCK_VQ_RX];
int val;
