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>

1 files changed, 4 insertions, 0 deletions

diff --git a/drivers/infiniband/hw/mlx5/qp.c b/drivers/infiniband/hw/mlx5/qp.c
index e3881433f5d7..8a36fd78c89f 100644
--- 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);