Index: head/sys/dev/mpr/mpr_sas.c
===================================================================
--- head/sys/dev/mpr/mpr_sas.c
+++ head/sys/dev/mpr/mpr_sas.c
@@ -1846,8 +1846,12 @@
 
 	if (csio->ccb_h.flags & CAM_CDB_POINTER)
 		bcopy(csio->cdb_io.cdb_ptr, &req->CDB.CDB32[0], csio->cdb_len);
-	else
+	else {
+		KASSERT(csio->cdb_len <= IOCDBLEN,
+		    ("cdb_len %d is greater than IOCDBLEN but CAM_CDB_POINTER is not set",
+		     csio->cdb_len));
 		bcopy(csio->cdb_io.cdb_bytes, &req->CDB.CDB32[0],csio->cdb_len);
+	}
 	req->IoFlags = htole16(csio->cdb_len);
 
 	/*
@@ -2429,6 +2433,7 @@
 		 * driver is being shutdown.
 		 */
 		if ((csio->cdb_io.cdb_bytes[0] == INQUIRY) &&
+		    (csio->data_ptr != NULL) &&
 		    ((csio->data_ptr[0] & 0x1f) == T_DIRECT) &&
 		    (sc->mapping_table[target_id].device_info &
 		    MPI2_SAS_DEVICE_INFO_SATA_DEVICE) &&
Index: head/sys/dev/mpr/mpr_sas_lsi.c
===================================================================
--- head/sys/dev/mpr/mpr_sas_lsi.c
+++ head/sys/dev/mpr/mpr_sas_lsi.c
@@ -1074,6 +1074,7 @@
 		mpr_free_command(sc, cm);
 	else if (error == 0)
 		error = EWOULDBLOCK;
+	cm->cm_data = NULL;
 	free(buffer, M_MPR);
 	return (error);
 }
@@ -1214,18 +1215,18 @@
 			continue;
 		}
 
-		ccb = xpt_alloc_ccb_nowait();
-		if (ccb == NULL) {
-			mpr_dprint(sc, MPR_FAULT, "Unable to alloc CCB to stop "
-			    "unit.\n");
-			return;
-		}
-
 		/*
 		 * The stop_at_shutdown flag will be set if this device is
 		 * a SATA direct-access end device.
 		 */
 		if (target->stop_at_shutdown) {
+			ccb = xpt_alloc_ccb_nowait();
+			if (ccb == NULL) {
+				mpr_dprint(sc, MPR_FAULT, "Unable to alloc CCB to stop "
+				    "unit.\n");
+				return;
+			}
+
 			if (xpt_create_path(&ccb->ccb_h.path, xpt_periph,
 			    pathid, targetid, CAM_LUN_WILDCARD) !=
 			    CAM_REQ_CMP) {