diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
index 5cbc51899de0..d73e506e9ba5 100644
--- a/drivers/scsi/libiscsi.c
+++ b/drivers/scsi/libiscsi.c
@@ -1191,7 +1191,7 @@ struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *conn, itt_t itt)
 		session->tt->parse_pdu_itt(conn, itt, &i, NULL);
 	else
 		i = get_itt(itt);
-	if (i >= session->cmds_max)
+	if (i < 0 || i >= session->cmds_max)
 		return NULL;
 
 	return session->cmds[i];
@@ -1384,7 +1384,7 @@ int iscsi_verify_itt(struct iscsi_conn *conn, itt_t itt)
 		return ISCSI_ERR_BAD_ITT;
 	}
 
-	if (i >= session->cmds_max) {
+	if (i < 0 || i >= session->cmds_max) {
 		iscsi_conn_printk(KERN_ERR, conn,
 				  "received invalid itt index %u (max cmds "
 				   "%u.\n", i, session->cmds_max);