nexthop_init() ignores errors from register_pernet_subsys() and
register_netdevice_notifier(), so a partial initialization can appear
successful.
Check those steps and unwind prior registrations on failure.
Do not check rtnl_register_many(): for built-in code it panics on
failure, so the call cannot return an error to nexthop_init().
Cc: stable+noautosel@kernel.org # untested fix to unlikely error path
Signed-off-by: Minhong He <heminhong@kylinos.cn>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260731025249.80026-1-heminhong@kylinos.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
c0fd47726c