From 172af3722ef34876f5e33bdf63c10d46573a2864 Mon Sep 17 00:00:00 2001 From: Ramil Kalimullin Date: Fri, 29 Jan 2010 13:17:57 +0400 Subject: Fix for bug#49897: crash in ptr_compare when char(0) NOT NULL column is used for ORDER BY Problem: filesort isn't meant for null length sort data (e.g. char(0)), that leads to a server crash. Fix: disregard sort order if sort data record length is 0 (nothing to sort). mysql-test/r/select.result: Fix for bug#49897: crash in ptr_compare when char(0) NOT NULL column is used for ORDER BY - test result. mysql-test/t/select.test: Fix for bug#49897: crash in ptr_compare when char(0) NOT NULL column is used for ORDER BY - test case. sql/filesort.cc: Fix for bug#49897: crash in ptr_compare when char(0) NOT NULL column is used for ORDER BY - assert added as filesort cannot handle null length sort data. sql/sql_select.cc: Fix for bug#49897: crash in ptr_compare when char(0) NOT NULL column is used for ORDER BY - don't sort null length data e.g. in case of ORDER BY CHAR(0). --- sql/filesort.cc | 2 ++ 1 file changed, 2 insertions(+) (limited to 'sql/filesort.cc') diff --git a/sql/filesort.cc b/sql/filesort.cc index f56e5b3a771..11be5d7f672 100644 --- a/sql/filesort.cc +++ b/sql/filesort.cc @@ -134,6 +134,8 @@ ha_rows filesort(THD *thd, TABLE *table, SORT_FIELD *sortorder, uint s_length, error= 1; bzero((char*) ¶m,sizeof(param)); param.sort_length= sortlength(thd, sortorder, s_length, &multi_byte_charset); + /* filesort cannot handle zero-length records. */ + DBUG_ASSERT(param.sort_length); param.ref_length= table->file->ref_length; param.addon_field= 0; param.addon_length= 0; -- cgit v1.2.1