[#MDEV-3908] crash in multi-table delete and mdl

will crash the server when the client disconnects. Crash happens when trying to free THD::st_transaction::mem_root, because mem_root->free->next pointer is corrupted. It's corrupted in here

#0  0x00007ffff602e660 in __stpcpy_sse2_unaligned () from /lib64/libc.so.6

#1  0x00000000006c3ace in MDL_key::mdl_key_init (this=0x7fffdc0067f8,

    mdl_namespace=MDL_key::TABLE, db=0x7fffdc006990 'Z' <repeats 6778 times>,

    name=0x7fffdc00ecb8 'Z' <repeats 10000 times>, "ROM")

    at /home/serg/Abk/mysql/5.5/sql/mdl.h:246

#2  0x000000000071b7af in MDL_request::init (this=0x7fffdc0067d8,

    mdl_namespace=MDL_key::TABLE,

    db_arg=0x7fffdc006990 'Z' <repeats 6778 times>,

    name_arg=0x7fffdc00ecb8 'Z' <repeats 10000 times>, "ROM",

    mdl_type_arg=MDL_SHARED_WRITE, mdl_duration_arg=MDL_TRANSACTION)

    at /home/serg/Abk/mysql/5.5/sql/mdl.cc:1003

#3  0x000000000062834c in st_select_lex::add_table_to_list (this=0x1e0cfe8,

    thd=0x1e0a4e0, table=0x7fffdc0063a0, alias=0x0, table_options=9,

    lock_type=TL_WRITE_DEFAULT, mdl_type=MDL_SHARED_WRITE,

    index_hints_arg=0x0, option=0x0)

    at /home/serg/Abk/mysql/5.5/sql/sql_parse.cc:6114

#4  0x000000000077a4a5 in MYSQLparse (yythd=0x1e0a4e0)

    at /home/serg/Abk/mysql/5.5/sql/sql_yacc.yy:11216

[MDEV-3908] crash in multi-table delete and mdl Created: 2012-12-02 Updated: 2013-01-18 Resolved: 2013-01-17
Status:	Closed
Project:	MariaDB Server
Component/s:	None
Affects Version/s:	5.5.28a
Fix Version/s:	5.5.29

[MDEV-3908] crash in multi-table delete and mdl Created: 2012-12-02 Updated: 2013-01-18 Resolved: 2013-01-17