RDMA/ucma: ucma_context reference leak in error path

RDMA/ucma: ucma_context reference leak in error path

commit ef95a90ae6f4f21990e1f7ced6719784a409e811 upstream.

Validating input parameters should be done before getting the cm_id
otherwise it can leak a cm_id reference.

Fixes: 6a21dfc0d0db ("RDMA/ucma: Limit possible option size")
Signed-off-by: Shamir Rabinovitch <shamir.rabinovitch@oracle.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
[iwamatsu: Backported to 4.4, 4.9 and 4.14: adjust context]
Signed-off-by: Nobuhiro Iwamatsu (CIP) <nobuhiro1.iwamatsu@toshiba.co.jp>
Signed-off-by: Sasha Levin <sashal@kernel.org>