IB/mlx5: Fix overflow check in IB_WR_FAST_REG_MR

Make sure not to overflow when reading the page list from struct
ib_fast_reg_page_list.

Signed-off-by: Eli Cohen <eli@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

diff --git a/drivers/infiniband/hw/mlx5/qp.c b/drivers/infiniband/hw/mlx5/qp.c
index e388143..8a36fd7 100644 (file)
--- a/drivers/infiniband/hw/mlx5/qp.c
+++ b/drivers/infiniband/hw/mlx5/qp.c
@@ -1915,6 +1915,10 @@ static int set_frwr_li_wr(void **seg, struct ib_send_wr *wr, int *size,
        if (unlikely((*seg == qp->sq.qend)))
                *seg = mlx5_get_send_wqe(qp, 0);
        if (!li) {
+               if (unlikely(wr->wr.fast_reg.page_list_len >
+                            wr->wr.fast_reg.page_list->max_page_list_len))
+                       return  -ENOMEM;
+
                set_frwr_pages(*seg, wr, mdev, pd, writ);
                *seg += sizeof(struct mlx5_wqe_data_seg);
                *size += (sizeof(struct mlx5_wqe_data_seg) / 16);