Split virtio_transport_recv_pkt() so socket lookup is separate from receive state machine processing under the socket lock. This prepares the receive path to keep a looked-up socket across multiple packets in a later change.
Keep virtio_transport_recv_pkt() on its existing per-packet locking path. The locked helper obtains packet-specific addresses from the skb and uses the matched socket namespace for reset replies. Preserve source validation and failure handling. No functional change intended. Signed-off-by: Jia Jia <[email protected]> --- net/vmw_vsock/virtio_transport_common.c | 128 ++++++++++++++---------- 1 file changed, 75 insertions(+), 53 deletions(-) diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c index f225f53ed4bab..61ee3bc205d5d 100644 --- a/net/vmw_vsock/virtio_transport_common.c +++ b/net/vmw_vsock/virtio_transport_common.c @@ -1774,81 +1774,60 @@ static bool virtio_transport_valid_type(u16 type) (type == VIRTIO_VSOCK_TYPE_SEQPACKET); } -/* We are under the virtio-vsock's vsock->rx_lock or vhost-vsock's vq->mutex - * lock. - */ -void virtio_transport_recv_pkt(struct virtio_transport *t, - struct sk_buff *skb, struct net *net) +static struct sock * +virtio_transport_find_socket(struct sk_buff *skb, struct sockaddr_vm *src, + struct sockaddr_vm *dst, struct net *net) { struct virtio_vsock_hdr *hdr = virtio_vsock_hdr(skb); - struct sockaddr_vm src, dst; - struct vsock_sock *vsk; struct sock *sk; - bool space_available; - - vsock_addr_init(&src, le64_to_cpu(hdr->src_cid), - le32_to_cpu(hdr->src_port)); - vsock_addr_init(&dst, le64_to_cpu(hdr->dst_cid), - le32_to_cpu(hdr->dst_port)); - - trace_virtio_transport_recv_pkt(src.svm_cid, src.svm_port, - dst.svm_cid, dst.svm_port, - le32_to_cpu(hdr->len), - le16_to_cpu(hdr->type), - le16_to_cpu(hdr->op), - le32_to_cpu(hdr->flags), - le32_to_cpu(hdr->buf_alloc), - le32_to_cpu(hdr->fwd_cnt)); - if (!virtio_transport_valid_type(le16_to_cpu(hdr->type))) { - (void)virtio_transport_reset_no_sock(t, skb, net); - goto free_pkt; - } + if (!virtio_transport_valid_type(le16_to_cpu(hdr->type))) + return NULL; - /* The socket must be in connected or bound table - * otherwise send reset back - */ - sk = vsock_find_connected_socket_net(&src, &dst, net); - if (!sk) { - sk = vsock_find_bound_socket_net(&dst, net); - if (!sk) { - (void)virtio_transport_reset_no_sock(t, skb, net); - goto free_pkt; - } - } + sk = vsock_find_connected_socket_net(src, dst, net); + if (!sk) + sk = vsock_find_bound_socket_net(dst, net); + if (!sk) + return NULL; if (virtio_transport_get_type(sk) != le16_to_cpu(hdr->type)) { - (void)virtio_transport_reset_no_sock(t, skb, net); sock_put(sk); - goto free_pkt; + return NULL; } - if (!skb_set_owner_sk_safe(skb, sk)) { - WARN_ONCE(1, "receiving vsock socket has sk_refcnt == 0\n"); - goto free_pkt; - } + return sk; +} - vsk = vsock_sk(sk); +/* + * The caller holds sk's socket lock and must free skb if this returns true. + */ +static bool +virtio_transport_recv_pkt_locked(struct virtio_transport *t, + struct sk_buff *skb, struct sock *sk) +{ + struct virtio_vsock_hdr *hdr = virtio_vsock_hdr(skb); + struct sockaddr_vm src; + struct vsock_sock *vsk = vsock_sk(sk); + bool space_available; - lock_sock(sk); + vsock_addr_init(&src, le64_to_cpu(hdr->src_cid), + le32_to_cpu(hdr->src_port)); - /* Check if sk has been closed or assigned to another transport before - * lock_sock (note: listener sockets are not assigned to any transport) + /* Listener sockets accept packets from any source and are not assigned to + * a transport. */ if (sock_flag(sk, SOCK_DONE) || (sk->sk_state != TCP_LISTEN && !vsock_check_source(vsk, &t->transport, &src))) { - (void)virtio_transport_reset_no_sock(t, skb, net); - release_sock(sk); - sock_put(sk); - goto free_pkt; + (void)virtio_transport_reset_no_sock(t, skb, sock_net(sk)); + return true; } space_available = virtio_transport_space_update(sk, skb); /* Update CID in case it has changed after a transport reset event */ if (vsk->local_addr.svm_cid != VMADDR_CID_ANY) - vsk->local_addr.svm_cid = dst.svm_cid; + vsk->local_addr.svm_cid = le64_to_cpu(hdr->dst_cid); if (space_available) sk->sk_write_space(sk); @@ -1870,17 +1849,60 @@ void virtio_transport_recv_pkt(struct virtio_transport *t, kfree_skb(skb); break; default: - (void)virtio_transport_reset_no_sock(t, skb, net); + (void)virtio_transport_reset_no_sock(t, skb, sock_net(sk)); kfree_skb(skb); break; } + return false; +} + +/* We are under the virtio-vsock's vsock->rx_lock or vhost-vsock's vq->mutex + * lock. + */ +void virtio_transport_recv_pkt(struct virtio_transport *t, + struct sk_buff *skb, struct net *net) +{ + struct virtio_vsock_hdr *hdr = virtio_vsock_hdr(skb); + struct sockaddr_vm src, dst; + struct sock *sk; + bool free_pkt; + + vsock_addr_init(&src, le64_to_cpu(hdr->src_cid), + le32_to_cpu(hdr->src_port)); + vsock_addr_init(&dst, le64_to_cpu(hdr->dst_cid), + le32_to_cpu(hdr->dst_port)); + + trace_virtio_transport_recv_pkt(src.svm_cid, src.svm_port, + dst.svm_cid, dst.svm_port, + le32_to_cpu(hdr->len), + le16_to_cpu(hdr->type), + le16_to_cpu(hdr->op), + le32_to_cpu(hdr->flags), + le32_to_cpu(hdr->buf_alloc), + le32_to_cpu(hdr->fwd_cnt)); + + sk = virtio_transport_find_socket(skb, &src, &dst, net); + if (!sk) { + (void)virtio_transport_reset_no_sock(t, skb, net); + goto free_pkt; + } + + if (!skb_set_owner_sk_safe(skb, sk)) { + WARN_ONCE(1, "receiving vsock socket has sk_refcnt == 0\n"); + goto free_pkt; + } + + lock_sock(sk); + free_pkt = virtio_transport_recv_pkt_locked(t, skb, sk); release_sock(sk); /* Release refcnt obtained when we fetched this socket out of the * bound or connected list. */ sock_put(sk); + if (free_pkt) + kfree_skb(skb); return; free_pkt: -- 2.53.0
