IB/mlx5: Fix leaking stack memory to userspace

mlx5_ib_create_qp_resp was never initialized and only the first 4 bytes
were written.

Fixes: 41d902cb7c32 ("RDMA/mlx5: Fix definition of mlx5_ib_create_qp_resp")
Cc: <stable@vger.kernel.org>
Acked-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
static int set_psv_wr(struct ib_sig_domain *domain,
		      u32 psv_idx, void **seg, int *size)
{
	struct mlx5_seg_set_psv *psv_seg = *seg;

	memset(psv_seg, 0, sizeof(*psv_seg));
	psv_seg->psv_num = cpu_to_be32(psv_idx);
	switch (domain->sig_type) {
	case IB_SIG_TYPE_NONE:
		break;
	case IB_SIG_TYPE_T10_DIF:
		psv_seg->transient_sig = cpu_to_be32(domain->sig.dif.bg << 16 |
						     domain->sig.dif.app_tag);
		psv_seg->ref_tag = cpu_to_be32(domain->sig.dif.ref_tag);
		break;
	default:
		pr_err("Bad signature type (%d) is given.\n",
		       domain->sig_type);
		return -EINVAL;
	}

	*seg += sizeof(*psv_seg);
	*size += sizeof(*psv_seg) / 16;

	return 0;
}

static int set_psv_wr(struct ib_sig_domain *domain,
		      u32 psv_idx, void **seg, int *size)
{
	struct mlx5_seg_set_psv *psv_seg = *seg;

	memset(psv_seg, 0, sizeof(*psv_seg));
	psv_seg->psv_num = cpu_to_be32(psv_idx);
	switch (domain->sig_type) {
	case IB_SIG_TYPE_NONE:
		break;
	case IB_SIG_TYPE_T10_DIF:
		psv_seg->transient_sig = cpu_to_be32(domain->sig.dif.bg << 16 |
						     domain->sig.dif.app_tag);
		psv_seg->ref_tag = cpu_to_be32(domain->sig.dif.ref_tag);
		break;
	default:
		pr_err("Bad signature type (%d) is given.\n",
		       domain->sig_type);
		return -EINVAL;
	}

	*seg += sizeof(*psv_seg);
	*size += sizeof(*psv_seg) / 16;

	return 0;
}
