IB/core: For multicast functions, verify that LIDs are multicast LIDs

The Infiniband spec defines "A multicast address is defined by a
MGID and a MLID" (section 10.5).  Currently the MLID value is not
validated.

Add check to verify that the MLID value is in the correct address
range.

Fixes: 0c33aee ("[IB] Add checks to multicast attach and detach")
Cc: [email protected]
Reviewed-by: Ira Weiny <[email protected]>
Reviewed-by: Dasaratharaman Chandramouli <[email protected]>
Signed-off-by: Michael J. Ruhl <[email protected]>
Signed-off-by: Dennis Dalessandro <[email protected]>
Reviewed-by: Leon Romanovsky <[email protected]>
Signed-off-by: Doug Ledford <[email protected]>

Author: mjruhl

drivers/infiniband/core/verbs.c

@@ -1519,7 +1519,9 @@ int ib_attach_mcast(struct ib_qp *qp, union ib_gid *gid, u16 lid)
 
 	if (!qp->device->attach_mcast)
 		return -ENOSYS;
-	if (gid->raw[0] != 0xff || qp->qp_type != IB_QPT_UD)
+	if (gid->raw[0] != 0xff || qp->qp_type != IB_QPT_UD ||
+	    lid < be16_to_cpu(IB_MULTICAST_LID_BASE) ||
+	    lid == be16_to_cpu(IB_LID_PERMISSIVE))
 		return -EINVAL;
 
 	ret = qp->device->attach_mcast(qp, gid, lid);
@@ -1535,7 +1537,9 @@ int ib_detach_mcast(struct ib_qp *qp, union ib_gid *gid, u16 lid)
 
 	if (!qp->device->detach_mcast)
 		return -ENOSYS;
-	if (gid->raw[0] != 0xff || qp->qp_type != IB_QPT_UD)
+	if (gid->raw[0] != 0xff || qp->qp_type != IB_QPT_UD ||
+	    lid < be16_to_cpu(IB_MULTICAST_LID_BASE) ||
+	    lid == be16_to_cpu(IB_LID_PERMISSIVE))
 		return -EINVAL;
 
 	ret = qp->device->detach_mcast(qp, gid, lid);