IB/mthca: check RDMA limits

Add limit checking on rd_atomic and dest_rd_atomic attributes:
especially for max_dest_rd_atomic, a value that is larger than HCA
capability can cause RDB overflow and corruption of another QP.

Signed-off-by: Jack Morgenstein <jackm@mellanox.co.il>
Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 14 insertions, 0 deletions

diff --git a/drivers/infiniband/hw/mthca/mthca_qp.c b/drivers/infiniband/hw/mthca/mthca_qp.c
index 7450550db736..c5c3d0edbbf5 100644
--- a/drivers/infiniband/hw/mthca/mthca_qp.c
+++ b/drivers/infiniband/hw/mthca/mthca_qp.c
@@ -591,6 +591,20 @@ int mthca_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr, int attr_mask)
                 return -EINVAL;
         }
 
+        if (attr_mask & IB_QP_MAX_QP_RD_ATOMIC &&
+            attr->max_rd_atomic > dev->limits.max_qp_init_rdma) {
+                mthca_dbg(dev, "Max rdma_atomic as initiator %u too large (max is %d)\n",
+                          attr->max_rd_atomic, dev->limits.max_qp_init_rdma);
+                return -EINVAL;
+        }
+
+        if (attr_mask & IB_QP_MAX_DEST_RD_ATOMIC &&
+            attr->max_dest_rd_atomic > 1 << dev->qp_table.rdb_shift) {
+                mthca_dbg(dev, "Max rdma_atomic as responder %u too large (max %d)\n",
+                          attr->max_dest_rd_atomic, 1 << dev->qp_table.rdb_shift);
+                return -EINVAL;
+        }
+
         mailbox = mthca_alloc_mailbox(dev, GFP_KERNEL);
         if (IS_ERR(mailbox))
                 return PTR_ERR(mailbox);