IB/core: Validate route when we init ah

In order to make sure API users don't try to use SGIDs which don't
conform to the routing table, validate the route before searching
the RoCE GID table.

Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

1 files changed, 35 insertions, 13 deletions

diff --git a/drivers/infiniband/core/verbs.c b/drivers/infiniband/core/verbs.c
index b25e5fbac5a4..063210be26ed 100644
--- a/drivers/infiniband/core/verbs.c
+++ b/drivers/infiniband/core/verbs.c
@@ -451,30 +451,52 @@ int ib_init_ah_from_wc(struct ib_device *device, u8 port_num,
 		return ret;
 
 	if (rdma_protocol_roce(device, port_num)) {
+		int if_index = 0;
 		u16 vlan_id = wc->wc_flags & IB_WC_WITH_VLAN ?
 				wc->vlan_id : 0xffff;
+		struct net_device *idev;
+		struct net_device *resolved_dev;
 
 		if (!(wc->wc_flags & IB_WC_GRH))
 			return -EPROTOTYPE;
 
-		if (!(wc->wc_flags & IB_WC_WITH_SMAC) ||
-		    !(wc->wc_flags & IB_WC_WITH_VLAN)) {
-			ret = rdma_addr_find_dmac_by_grh(&dgid, &sgid,
-							 ah_attr->dmac,
-							 wc->wc_flags & IB_WC_WITH_VLAN ?
-							 NULL : &vlan_id,
-							 0);
-			if (ret)
-				return ret;
+		if (!device->get_netdev)
+			return -EOPNOTSUPP;
+
+		idev = device->get_netdev(device, port_num);
+		if (!idev)
+			return -ENODEV;
+
+		ret = rdma_addr_find_dmac_by_grh(&dgid, &sgid,
+						 ah_attr->dmac,
+						 wc->wc_flags & IB_WC_WITH_VLAN ?
+						 NULL : &vlan_id,
+						 &if_index);
+		if (ret) {
+			dev_put(idev);
+			return ret;
 		}
 
+		resolved_dev = dev_get_by_index(&init_net, if_index);
+		if (resolved_dev->flags & IFF_LOOPBACK) {
+			dev_put(resolved_dev);
+			resolved_dev = idev;
+			dev_hold(resolved_dev);
+		}
+		rcu_read_lock();
+		if (resolved_dev != idev && !rdma_is_upper_dev_rcu(idev,
+								   resolved_dev))
+			ret = -EHOSTUNREACH;
+		rcu_read_unlock();
+		dev_put(idev);
+		dev_put(resolved_dev);
+		if (ret)
+			return ret;
+
 		ret = get_sgid_index_from_eth(device, port_num, vlan_id,
 					      &dgid, gid_type, &gid_index);
 		if (ret)
 			return ret;
-
-		if (wc->wc_flags & IB_WC_WITH_SMAC)
-			memcpy(ah_attr->dmac, wc->smac, ETH_ALEN);
 	}
 
 	ah_attr->dlid = wc->slid;
@@ -1139,7 +1161,7 @@ int ib_resolve_eth_dmac(struct ib_qp *qp,
 			ret = rdma_addr_find_dmac_by_grh(&sgid,
 							 &qp_attr->ah_attr.grh.dgid,
 							 qp_attr->ah_attr.dmac,
-							 NULL, ifindex);
+							 NULL, &ifindex);
 
 			dev_put(sgid_attr.ndev);
 		}