| From ce7536bc7398e2ae552d2fabb7e0e371a9f1fe46 Mon Sep 17 00:00:00 2001 |
| From: Stefano Garzarella <sgarzare@redhat.com> |
| Date: Mon, 8 Feb 2021 15:44:54 +0100 |
| Subject: vsock/virtio: update credit only if socket is not closed |
| |
| From: Stefano Garzarella <sgarzare@redhat.com> |
| |
| 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 <sgarzare@redhat.com> |
| Acked-by: Michael S. Tsirkin <mst@redhat.com> |
| Link: https://lore.kernel.org/r/20210208144454.84438-1-sgarzare@redhat.com |
| Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| net/vmw_vsock/virtio_transport_common.c | 4 ++-- |
| 1 file changed, 2 insertions(+), 2 deletions(-) |
| |
| --- a/net/vmw_vsock/virtio_transport_common.c |
| +++ b/net/vmw_vsock/virtio_transport_common.c |
| @@ -1033,10 +1033,10 @@ void virtio_transport_recv_pkt(struct vi |
| |
| 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; |
| |
