From fd51e810affa38d735d04261e673b2a5fe9c8665 Mon Sep 17 00:00:00 2001 From: Dudu Lu Date: Mon, 13 Apr 2026 21:14:09 +0800 Subject: [PATCH] vsock/virtio: fix accept queue count leak on transport mismatch commit 52bcb57a4e8a0865a76c587c2451906342ae1b2d upstream. virtio_transport_recv_listen() calls sk_acceptq_added() before vsock_assign_transport(). If vsock_assign_transport() fails or selects a different transport, the error path returns without calling sk_acceptq_removed(), permanently incrementing sk_ack_backlog. After approximately backlog+1 such failures, sk_acceptq_is_full() returns true, causing the listener to reject all new connections. Fix by moving sk_acceptq_added() to after the transport validation, matching the pattern used by vmci_transport and hyperv_transport. Fixes: c0cfa2d8a788 ("vsock: add multi-transports support") Signed-off-by: Dudu Lu Reviewed-by: Bobby Eshleman Reviewed-by: Luigi Leonardi Reviewed-by: Stefano Garzarella Acked-by: Michael S. Tsirkin Link: https://patch.msgid.link/20260413131409.19022-1-phx0fer@gmail.com Signed-off-by: Paolo Abeni Signed-off-by: Luigi Leonardi Signed-off-by: Greg Kroah-Hartman --- net/vmw_vsock/virtio_transport_common.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c index ffd4db198bdf..12eb365c1603 100644 --- a/net/vmw_vsock/virtio_transport_common.c +++ b/net/vmw_vsock/virtio_transport_common.c @@ -1223,8 +1223,6 @@ virtio_transport_recv_listen(struct sock *sk, struct virtio_vsock_pkt *pkt, return -ENOMEM; } - sk_acceptq_added(sk); - lock_sock_nested(child, SINGLE_DEPTH_NESTING); child->sk_state = TCP_ESTABLISHED; @@ -1246,6 +1244,7 @@ virtio_transport_recv_listen(struct sock *sk, struct virtio_vsock_pkt *pkt, return ret; } + sk_acceptq_added(sk); if (virtio_transport_space_update(child, pkt)) child->sk_write_space(child);