RDMA/bnxt_re: Add check for path mtu in modify_qp

When RDMA app configures path MTU, add a check in modify_qp verb
to make sure that it doesn't go beyond interface MTU. If this
check fails, driver will fail the modify_qp verb.

Fixes: 1ac5a4047975 ("RDMA/bnxt_re: Add bnxt_re RoCE driver")
Reviewed-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Signed-off-by: Saravanan Vajravel <saravanan.vajravel@broadcom.com>
Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
Link: https://patch.msgid.link/20241211083931.968831-3-kalesh-anakkur.purayil@broadcom.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>

diff --git a/drivers/infiniband/hw/bnxt_re/ib_verbs.c b/drivers/infiniband/hw/bnxt_re/ib_verbs.c
index 215074c0860b865b0e68fc42ba8842800b97f70c..a609e1635a3d403e1335126f6a8d3d14a040c97c 100644 (file)
--- a/drivers/infiniband/hw/bnxt_re/ib_verbs.c
+++ b/drivers/infiniband/hw/bnxt_re/ib_verbs.c
@@ -2162,18 +2162,20 @@ int bnxt_re_modify_qp(struct ib_qp *ib_qp, struct ib_qp_attr *qp_attr,
                }
        }
 
-       if (qp_attr_mask & IB_QP_PATH_MTU) {
-               qp->qplib_qp.modify_flags |=
-                               CMDQ_MODIFY_QP_MODIFY_MASK_PATH_MTU;
-               qp->qplib_qp.path_mtu = __from_ib_mtu(qp_attr->path_mtu);
-               qp->qplib_qp.mtu = ib_mtu_enum_to_int(qp_attr->path_mtu);
-       } else if (qp_attr->qp_state == IB_QPS_RTR) {
-               qp->qplib_qp.modify_flags |=
-                       CMDQ_MODIFY_QP_MODIFY_MASK_PATH_MTU;
-               qp->qplib_qp.path_mtu =
-                       __from_ib_mtu(iboe_get_mtu(rdev->netdev->mtu));
-               qp->qplib_qp.mtu =
-                       ib_mtu_enum_to_int(iboe_get_mtu(rdev->netdev->mtu));
+       if (qp_attr->qp_state == IB_QPS_RTR) {
+               enum ib_mtu qpmtu;
+
+               qpmtu = iboe_get_mtu(rdev->netdev->mtu);
+               if (qp_attr_mask & IB_QP_PATH_MTU) {
+                       if (ib_mtu_enum_to_int(qp_attr->path_mtu) >
+                           ib_mtu_enum_to_int(qpmtu))
+                               return -EINVAL;
+                       qpmtu = qp_attr->path_mtu;
+               }
+
+               qp->qplib_qp.modify_flags |= CMDQ_MODIFY_QP_MODIFY_MASK_PATH_MTU;
+               qp->qplib_qp.path_mtu = __from_ib_mtu(qpmtu);
+               qp->qplib_qp.mtu = ib_mtu_enum_to_int(qpmtu);
        }
 
        if (qp_attr_mask & IB_QP_TIMEOUT) {