From: Stefano Garzarella Date: Mon, 8 Feb 2021 14:44:54 +0000 (+0100) Subject: vsock/virtio: update credit only if socket is not closed X-Git-Tag: v4.14.222~21 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e3bb32acc6f51fe0c41513e7ca1f4baba92f8fb7;p=thirdparty%2Fkernel%2Fstable.git 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 --- diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c index 8e4c13cc61ba8..349311f6d1958 100644 --- a/net/vmw_vsock/virtio_transport_common.c +++ b/net/vmw_vsock/virtio_transport_common.c @@ -1029,10 +1029,10 @@ 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;