From: YueHaibing <yuehaibing@xxxxxxxxxx> commit 80a316ff16276b36d0392a8f8b2f63259857ae98 upstream. If xenbus_register_frontend() fails in p9_trans_xen_init, we should call v9fs_unregister_trans() to do cleanup. Link: http://lkml.kernel.org/r/20190430143933.19368-1-yuehaibing@xxxxxxxxxx Cc: stable@xxxxxxxxxxxxxxx Fixes: 868eb122739a ("xen/9pfs: introduce Xen 9pfs transport driver") Signed-off-by: YueHaibing <yuehaibing@xxxxxxxxxx> Signed-off-by: Dominique Martinet <dominique.martinet@xxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/9p/trans_xen.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) --- a/net/9p/trans_xen.c +++ b/net/9p/trans_xen.c @@ -530,13 +530,19 @@ static struct xenbus_driver xen_9pfs_fro static int p9_trans_xen_init(void) { + int rc; + if (!xen_domain()) return -ENODEV; pr_info("Initialising Xen transport for 9pfs\n"); v9fs_register_trans(&p9_xen_trans); - return xenbus_register_frontend(&xen_9pfs_front_driver); + rc = xenbus_register_frontend(&xen_9pfs_front_driver); + if (rc) + v9fs_unregister_trans(&p9_xen_trans); + + return rc; } module_init(p9_trans_xen_init);