On Thu, Oct 23, 2025 at 11:27:45AM -0700, Bobby Eshleman wrote:
From: Bobby Eshleman bobbyeshleman@meta.com
Enable network namespace support in the virtio-vsock common transport layer by declaring namespace pointers in the transmit and receive paths.
The changes include:
- Add a 'net' field to virtio_vsock_pkt_info to carry the namespace
pointer for outgoing packets. 2. Store the namespace and namespace mode in the skb control buffer when allocating packets (except for VIRTIO_VSOCK_OP_RST packets which do not have an associated socket). 3. Retrieve namespace information from skbs on the receive path for lookups using vsock_find_connected_socket_net() and vsock_find_bound_socket_net().
This allows users of virtio transport common code (vhost-vsock/virtio-vsock) to later enable namespace support.
Signed-off-by: Bobby Eshleman bobbyeshleman@meta.com
Changes in v7:
- add comment explaining the !vsk case in virtio_transport_alloc_skb()
include/linux/virtio_vsock.h | 1 + net/vmw_vsock/virtio_transport_common.c | 21 +++++++++++++++++++-- 2 files changed, 20 insertions(+), 2 deletions(-)
diff --git a/include/linux/virtio_vsock.h b/include/linux/virtio_vsock.h index 29290395054c..f90646f82993 100644 --- a/include/linux/virtio_vsock.h +++ b/include/linux/virtio_vsock.h @@ -217,6 +217,7 @@ struct virtio_vsock_pkt_info { u32 remote_cid, remote_port; struct vsock_sock *vsk; struct msghdr *msg;
- struct net *net; u32 pkt_len; u16 type; u16 op;
diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c index dcc8a1d5851e..b8e52c71920a 100644 --- a/net/vmw_vsock/virtio_transport_common.c +++ b/net/vmw_vsock/virtio_transport_common.c @@ -316,6 +316,15 @@ static struct sk_buff *virtio_transport_alloc_skb(struct virtio_vsock_pkt_info * info->flags, zcopy);
- /*
* If there is no corresponding socket, then we don't have a* corresponding namespace. This only happens For VIRTIO_VSOCK_OP_RST.*/
So, in virtio_transport_recv_pkt() should we check that `net` is not set?
Should we set it to NULL here?
- if (vsk) {
virtio_vsock_skb_set_net(skb, info->net);
Ditto here about the net refcnt, can the net disappear? Should we use get_net() in some way, or the socket will prevent that?
virtio_vsock_skb_set_net_mode(skb, vsk->net_mode);- }
- return skb;
out: kfree_skb(skb); @@ -527,6 +536,7 @@ static int virtio_transport_send_credit_update(struct vsock_sock *vsk) struct virtio_vsock_pkt_info info = { .op = VIRTIO_VSOCK_OP_CREDIT_UPDATE, .vsk = vsk,
.net = sock_net(sk_vsock(vsk)),};
return virtio_transport_send_pkt_info(vsk, &info);
@@ -1067,6 +1077,7 @@ int virtio_transport_connect(struct vsock_sock *vsk) struct virtio_vsock_pkt_info info = { .op = VIRTIO_VSOCK_OP_REQUEST, .vsk = vsk,
.net = sock_net(sk_vsock(vsk)),};
return virtio_transport_send_pkt_info(vsk, &info);
@@ -1082,6 +1093,7 @@ int virtio_transport_shutdown(struct vsock_sock *vsk, int mode) (mode & SEND_SHUTDOWN ? VIRTIO_VSOCK_SHUTDOWN_SEND : 0), .vsk = vsk,
.net = sock_net(sk_vsock(vsk)),};
return virtio_transport_send_pkt_info(vsk, &info);
@@ -1108,6 +1120,7 @@ virtio_transport_stream_enqueue(struct vsock_sock *vsk, .msg = msg, .pkt_len = len, .vsk = vsk,
.net = sock_net(sk_vsock(vsk)),};
return virtio_transport_send_pkt_info(vsk, &info);
@@ -1145,6 +1158,7 @@ static int virtio_transport_reset(struct vsock_sock *vsk, .op = VIRTIO_VSOCK_OP_RST, .reply = !!skb, .vsk = vsk,
.net = sock_net(sk_vsock(vsk)),};
/* Send RST only if the original pkt is not a RST pkt */
@@ -1465,6 +1479,7 @@ virtio_transport_send_response(struct vsock_sock *vsk, .remote_port = le32_to_cpu(hdr->src_port), .reply = true, .vsk = vsk,
.net = sock_net(sk_vsock(vsk)),};
return virtio_transport_send_pkt_info(vsk, &info);
@@ -1578,7 +1593,9 @@ static bool virtio_transport_valid_type(u16 type) void virtio_transport_recv_pkt(struct virtio_transport *t, struct sk_buff *skb) {
- enum vsock_net_mode net_mode = virtio_vsock_skb_net_mode(skb); struct virtio_vsock_hdr *hdr = virtio_vsock_hdr(skb);
- struct net *net = virtio_vsock_skb_net(skb);
Okay, so this is where the skb net is read, so why we touch the virtio-vsock driver (virtio_transport.c) in the other patch where we changed just af_vsock.c?
IMO we should move that change here, or in a separate commit. Or maybe I missed some dependency :-)
Thanks, Stefano
struct sockaddr_vm src, dst; struct vsock_sock *vsk; struct sock *sk; @@ -1606,9 +1623,9 @@ void virtio_transport_recv_pkt(struct virtio_transport *t, /* The socket must be in connected or bound table * otherwise send reset back */
- sk = vsock_find_connected_socket(&src, &dst);
- sk = vsock_find_connected_socket_net(&src, &dst, net, net_mode); if (!sk) {
sk = vsock_find_bound_socket(&dst);
sk = vsock_find_bound_socket_net(&dst, net, net_mode);-- 2.47.3