diff --git a/drivers/scsi/pmcraid.c b/drivers/scsi/pmcraid.c
index fca6a89..d079f9a 100644
--- a/drivers/scsi/pmcraid.c
+++ b/drivers/scsi/pmcraid.c
@@ -3871,6 +3871,9 @@
 			pmcraid_err("couldn't build passthrough ioadls\n");
 			goto out_free_buffer;
 		}
+	} else if (request_size < 0) {
+		rc = -EINVAL;
+		goto out_free_buffer;
 	}
 
 	/* If data is being written into the device, copy the data from user