From c025081b57df63f5a0b92ab57855904108c059d7 Mon Sep 17 00:00:00 2001 From: Stefano Garzarella Date: Mon, 8 Feb 2021 15:44:54 +0100 Subject: [PATCH] vsock/virtio: update credit only if socket is not closed commit ce7536bc7398e2ae552d2fabb7e0e371a9f1fe46 upstream. If the socket is closed or is being released, some resources used by virtio_transport_space_update() such as 'vsk->trans' may be released. To avoid a use after free bug we should only update the available credit when we are sure the socket is still open and we have the lock held. Fixes: 06a8fc78367d ("VSOCK: Introduce virtio_vsock_common.ko") Signed-off-by: Stefano Garzarella Acked-by: Michael S. Tsirkin Link: https://lore.kernel.org/r/20210208144454.84438-1-sgarzare@redhat.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- net/vmw_vsock/virtio_transport_common.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c index efbb521bff13..dde16a033a09 100644 --- a/net/vmw_vsock/virtio_transport_common.c +++ b/net/vmw_vsock/virtio_transport_common.c @@ -1100,10 +1100,10 @@ void virtio_transport_recv_pkt(struct virtio_transport *t, vsk = vsock_sk(sk); - space_available = virtio_transport_space_update(sk, pkt); - lock_sock(sk); + space_available = virtio_transport_space_update(sk, pkt); + /* Update CID in case it has changed after a transport reset event */ vsk->local_addr.svm_cid = dst.svm_cid;