scsi: iscsi: Fix completion check during abort races

We have a ref to the task being aborted, so SCp.ptr will never be NULL. We
need to use iscsi_task_is_completed to check for the completed state.

Link: https://lore.kernel.org/r/20210525181821.7617-16-michael.christie@oracle.com
Reviewed-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/libiscsi.c

@@ -2338,7 +2338,7 @@ int iscsi_eh_abort(struct scsi_cmnd *sc)
 		iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
 		goto failed_unlocked;
 	case TMF_NOT_FOUND:
-		if (!sc->SCp.ptr) {
+		if (iscsi_task_is_completed(task)) {
 			session->tmf_state = TMF_INITIAL;
 			memset(hdr, 0, sizeof(*hdr));
 			/* task completed before tmf abort response */