Commit 344c24d3 authored by monty@mashka.mysql.fi's avatar monty@mashka.mysql.fi
Browse files

Fixed core dump bug in ORDER BY ... LIMIT

parent 75a39efa

Docs/manual.texi

+2 −0
Original line number Diff line number Diff line
@@ -46929,6 +46929,8 @@ not yet 100% confident in this code. 
@appendixsubsec Changes in release 3.23.53

@itemize @bullet

@item

Fixed unlikely core dump with @code{SELECT ... ORDER BY ... LIMIT}.

@item

Changed @code{AND/OR} to report that they can return NULL. This fixes a

bug in @code{GROUP BY} on @code{AND/OR} expression that return

@code{NULL}.

sql/filesort.cc

+7 −2
Original line number Diff line number Diff line
@@ -378,13 +378,18 @@ static ha_rows find_all_keys(SORTPARAM *param, SQL_SELECT *select, 
	if (indexpos >= *maxbuffer ||

	    write_keys(param,sort_keys,idx,buffpek+indexpos,tempfile))

	      DBUG_RETURN(HA_POS_ERROR);

	idx=0; indexpos++;

	idx=0;

	if (param->ref_length == param->sort_length &&

	    my_b_tell(tempfile)/param->sort_length >= param->max_rows)

	{

	  /*

	    We are writing the result index file and have found all

	    rows that we need.  Abort the sort and return the result.

	  */

	  error=HA_ERR_END_OF_FILE;

	  break;			/* Found enough records */

	}

	indexpos++;

      }

      make_sortkey(param,sort_keys[idx++],ref_pos);

    }
@@ -399,7 +404,7 @@ static ha_rows find_all_keys(SORTPARAM *param, SQL_SELECT *select, 
    file->print_error(error,MYF(ME_ERROR | ME_WAITTANG)); /* purecov: inspected */

    DBUG_RETURN(HA_POS_ERROR);			/* purecov: inspected */

  }

  if (indexpos)

  if (indexpos && idx)

    if (indexpos >= *maxbuffer ||

	write_keys(param,sort_keys,idx,buffpek+indexpos,tempfile))

      DBUG_RETURN(HA_POS_ERROR);		/* purecov: inspected */