IB/mlx5: Skip non-ODP MR when handling a page fault

It is possible that we call pagefault_single_data_segment() with a MKey
that belongs to a memory region which is not on demand (i.e. pinned
pages). This can happen if, for instance, a WQE that points to multiple
MRs where some of them are ODP MRs and some are not.  In this case we
don't need to handle this MR in the ODP context besides reporting success.

Otherwise the code will call pagefault_mr() which will do to_ib_umem_odp()
on a non-ODP MR and thus access out of bounds.

Fixes: 7bdf65d4 ("IB/mlx5: Handle page faults")
Signed-off-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/hw/mlx5/odp.c

@@ -674,6 +674,14 @@ static int pagefault_single_data_segment(struct mlx5_ib_dev *dev,
 			goto srcu_unlock;
 		}
 
+		if (!mr->umem->is_odp) {
+			mlx5_ib_dbg(dev, "skipping non ODP MR (lkey=0x%06x) in page fault handler.\n",
+				    key);
+			if (bytes_mapped)
+				*bytes_mapped += bcnt;
+			goto srcu_unlock;
+		}
+
 		ret = pagefault_mr(dev, mr, io_virt, bcnt, bytes_mapped);
 		if (ret < 0)
 			goto srcu_unlock;