*** a/src/backend/access/transam/xlog.c
--- b/src/backend/access/transam/xlog.c
***************
*** 8057,8063 **** pg_stop_backup(PG_FUNCTION_ARGS)
  	 */
  	RequestXLogSwitch();
  
! 	XLByteToSeg(stoppoint, _logId, _logSeg);
  	XLogFileName(stopxlogfilename, ThisTimeLineID, _logId, _logSeg);
  
  	/* Use the log timezone here, not the session timezone */
--- 8057,8078 ----
  	 */
  	RequestXLogSwitch();
  
! 	if (stoppoint.xrecoff >= XLogSegSize)
! 	{
! 		XLogRecPtr	recptr = stoppoint;
! 
! 		/*
! 		 * Since xlog segment file name is calculated by using XLByteToSeg,
! 		 * it might indicate a nonexistent file (i.e., which ends in "FF")
! 		 * when we are crossing a logid boundary. In this case, we use the
! 		 * next reasonable file name instead of nonexistent one.
! 		 */
! 		recptr.xlogid += 1;
! 		recptr.xrecoff = XLOG_BLCKSZ;
! 		XLByteToSeg(recptr, _logId, _logSeg);
! 	}
! 	else
! 		XLByteToSeg(stoppoint, _logId, _logSeg);
  	XLogFileName(stopxlogfilename, ThisTimeLineID, _logId, _logSeg);
  
  	/* Use the log timezone here, not the session timezone */