commit 1e4b50f06d970d8da3474d2a0354450416710bda upstream. In order to have the padding fields actually usable in the future, there have to be checks that user space doesn't supply non-zero garbage there. It is also worth setting these padding fields to zero, unless it is known that they have been already zeroed. Cc: stable@vger.kernel.org # v5.15 Fixes: 5a20dd46b8b84593 ("mctp: Be explicit about struct sockaddr_mctp padding") Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com> Acked-by: Jeremy Kerr <jk@codeconstruct.com.au> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>