From a6650e78c428841da5d68904475c5d177f3d11ee Mon Sep 17 00:00:00 2001 From: Bobby Eshleman Date: Wed, 29 Mar 2023 16:51:58 +0000 Subject: [PATCH] virtio/vsock: fix leaks due to missing skb owner commit f9d2b1e146e0f82f3d04629afd92698522058361 upstream. This patch sets the skb owner in the recv and send path for virtio. For the send path, this solves the leak caused when virtio_transport_purge_skbs() finds skb->sk is always NULL and therefore never matches it with the current socket. Setting the owner upon allocation fixes this. For the recv path, this ensures correctness of accounting and also correct transfer of ownership in vsock_loopback (when skbs are sent from one socket and received by another). Fixes: 71dc9ec9ac7d ("virtio/vsock: replace virtio_vsock_pkt with sk_buff") Signed-off-by: Bobby Eshleman Reported-by: Cong Wang Link: https://lore.kernel.org/all/ZCCbATwov4U+GBUv@pop-os.localdomain/ Reviewed-by: Stefano Garzarella Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/vmw_vsock/virtio_transport_common.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c index 2b5ca5f18483..0762634dbaee 100644 --- a/net/vmw_vsock/virtio_transport_common.c +++ b/net/vmw_vsock/virtio_transport_common.c @@ -94,6 +94,11 @@ virtio_transport_alloc_skb(struct virtio_vsock_pkt_info *info, info->op, info->flags); + if (info->vsk && !skb_set_owner_sk_safe(skb, sk_vsock(info->vsk))) { + WARN_ONCE(1, "failed to allocate skb on vsock socket with sk_refcnt == 0\n"); + goto out; + } + return skb; out: @@ -1302,6 +1307,11 @@ void virtio_transport_recv_pkt(struct virtio_transport *t, 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; + } + vsk = vsock_sk(sk); lock_sock(sk); -- 2.34.1