Buffer overflow on instant ADD/DROP of generated column

CREATE TABLE v0 ( v1 TIME NOT NULL PRIMARY KEY ) ;

 ALTER TABLE v0 ADD COLUMN v0 INT GENERATED ALWAYS AS ( lpad ( 'x' , NULL = 32 , 'x' ) ) STORED ;

 SHOW LOCAL STATUS WHERE COALESCE ( 27 , 51 - 39 ) = 'x' ;

 DELETE FROM v0 WHERE 44707452.000000 ;

 ALTER TABLE v0 ADD COLUMN v0 INT GENERATED ALWAYS AS ( v1 + v1 ) , DROP COLUMN v0 ;

 SELECT COUNT ( * ) FROM v0 WHERE v1 = -128 AND v1 = 'x' ;

2021-08-16 14:41:38 0 [Note] InnoDB: Compressed tables use zlib 1.2.11

2021-08-16 14:41:38 0 [Note] InnoDB: Number of pools: 1

2021-08-16 14:41:38 0 [Note] InnoDB: Using crc32 + pclmulqdq instructions

2021-08-16 14:41:38 0 [Note] mysqld: O_TMPFILE is not supported on /tmp (disabling future attempts)

2021-08-16 14:41:38 0 [Note] InnoDB: Using liburing

2021-08-16 14:41:38 0 [Note] InnoDB: Initializing buffer pool, total size = 134217728, chunk size = 134217728

2021-08-16 14:41:38 0 [Note] InnoDB: Completed initialization of buffer pool

2021-08-16 14:41:38 0 [Note] InnoDB: 128 rollback segments are active.

2021-08-16 14:41:38 0 [Note] InnoDB: Creating shared tablespace for temporary tables

2021-08-16 14:41:38 0 [Note] InnoDB: Setting file './ibtmp1' size to 12 MB. Physically writing the file full; Please wait ...

2021-08-16 14:41:38 0 [Note] InnoDB: File './ibtmp1' size is now 12 MB.

2021-08-16 14:41:38 0 [Note] InnoDB: 10.7.0 started; log sequence number 42161; transaction id 14

2021-08-16 14:41:38 0 [Note] InnoDB: Loading buffer pool(s) from /home/fuboat/mariadb-tmp/mysql-default-data/ib_buffer_pool

2021-08-16 14:41:38 0 [Note] Plugin 'FEEDBACK' is disabled.

2021-08-16 14:41:38 0 [Note] InnoDB: Buffer pool(s) load completed at 210816 14:41:38

2021-08-16 14:41:38 0 [Note] Server socket created on IP: '0.0.0.0'.

2021-08-16 14:41:38 0 [Note] Server socket created on IP: '::'.

2021-08-16 14:41:38 0 [Note] /usr/local/mysql/bin//mysqld: ready for connections.

Version: '10.7.0-MariaDB'  socket: '/tmp/0.socket'  port: 3306  Source distribution

2021-08-16 14:41:39 0 [Note] /usr/local/mysql/bin//mysqld (initiated by: root[root] @ localhost []): Normal shutdown

2021-08-16 14:41:39 0 [Note] InnoDB: FTS optimize thread exiting.

2021-08-16 14:41:39 0 [Note] InnoDB: Starting shutdown...

2021-08-16 14:41:39 0 [Note] InnoDB: Dumping buffer pool(s) to /home/fuboat/mariadb-tmp/mysql-default-data/ib_buffer_pool

2021-08-16 14:41:39 0 [Note] InnoDB: Buffer pool(s) dump completed at 210816 14:41:39

2021-08-16 14:41:39 0 [Note] InnoDB: Removed temporary tablespace data file: "./ibtmp1"

2021-08-16 14:41:39 0 [Note] InnoDB: Shutdown completed; log sequence number 42173; transaction id 15

2021-08-16 14:41:39 0 [Note] /usr/local/mysql/bin//mysqld: Shutdown complete

2021-08-16 14:49:19 0 [Note] InnoDB: Compressed tables use zlib 1.2.11

2021-08-16 14:49:19 0 [Note] InnoDB: Number of pools: 1

2021-08-16 14:49:19 0 [Note] InnoDB: Using crc32 + pclmulqdq instructions

2021-08-16 14:49:19 0 [Note] mysqld: O_TMPFILE is not supported on /tmp (disabling future attempts)

2021-08-16 14:49:19 0 [Note] InnoDB: Using liburing

2021-08-16 14:49:19 0 [Note] InnoDB: Initializing buffer pool, total size = 134217728, chunk size = 134217728

2021-08-16 14:49:19 0 [Note] InnoDB: Completed initialization of buffer pool

2021-08-16 14:49:26 0 [Note] InnoDB: 128 rollback segments are active.

2021-08-16 14:49:26 0 [Note] InnoDB: Creating shared tablespace for temporary tables

2021-08-16 14:49:26 0 [Note] InnoDB: Setting file './ibtmp1' size to 12 MB. Physically writing the file full; Please wait ...

2021-08-16 14:49:26 0 [Note] InnoDB: File './ibtmp1' size is now 12 MB.

2021-08-16 14:49:26 0 [Note] InnoDB: 10.7.0 started; log sequence number 42173; transaction id 14

2021-08-16 14:49:26 0 [Note] InnoDB: Loading buffer pool(s) from /home/fuboat/mariadb-tmp/19/ib_buffer_pool

2021-08-16 14:49:26 0 [Note] Plugin 'FEEDBACK' is disabled.

2021-08-16 14:49:27 0 [Note] Server socket created on IP: '0.0.0.0'.

2021-08-16 14:49:27 0 [Note] Server socket created on IP: '::'.

2021-08-16 14:49:28 0 [Note] InnoDB: Buffer pool(s) load completed at 210816 14:49:28

2021-08-16 14:49:28 0 [Note] /usr/local/mysql/bin//mysqld: ready for connections.

Version: '10.7.0-MariaDB'  socket: '/tmp/19.socket'  port: 10019  Source distribution

=================================================================

==2119277==ERROR: AddressSanitizer: use-after-poison on address 0x6190000d6d60 at pc 0x55a3184baacf bp 0x7f47ed829920 sp 0x7f47ed829910

WRITE of size 64 at 0x6190000d6d60 thread T14

    #0 0x55a3184baace in prepare_inplace_add_virtual /experiment/mariadb-server/sql/field.h:1395

    #1 0x55a3184cc1db in prepare_inplace_alter_table_dict /experiment/mariadb-server/storage/innobase/handler/handler0alter.cc:6206

    #2 0x55a3184d9f06 in ha_innobase::prepare_inplace_alter_table(TABLE*, Alter_inplace_info*) /experiment/mariadb-server/storage/innobase/handler/handler0alter.cc:8270

    #3 0x55a3176a67d2 in mysql_inplace_alter_table /experiment/mariadb-server/sql/sql_table.cc:7326

    #4 0x55a3176a67d2 in mysql_alter_table(THD*, st_mysql_const_lex_string const*, st_mysql_const_lex_string const*, HA_CREATE_INFO*, TABLE_LIST*, Alter_info*, unsigned int, st_order*, bool, bool) /experiment/mariadb-server/sql/sql_table.cc:10205

    #5 0x55a3177fcf99 in Sql_cmd_alter_table::execute(THD*) /experiment/mariadb-server/sql/sql_alter.cc:550

    #6 0x55a31741717f in mysql_execute_command(THD*, bool) /experiment/mariadb-server/sql/sql_parse.cc:5997

    #7 0x55a3174245a0 in mysql_parse(THD*, char*, unsigned int, Parser_state*) /experiment/mariadb-server/sql/sql_parse.cc:8030

    #8 0x55a31742a60b in dispatch_command(enum_server_command, THD*, char*, unsigned int, bool) /experiment/mariadb-server/sql/sql_parse.cc:1896

    #9 0x55a31742f73c in do_command(THD*, bool) /experiment/mariadb-server/sql/sql_parse.cc:1404

    #10 0x55a3177eae56 in do_handle_one_connection(CONNECT*, bool) /experiment/mariadb-server/sql/sql_connect.cc:1418

    #11 0x55a3177eb33c in handle_one_connection /experiment/mariadb-server/sql/sql_connect.cc:1312

    #12 0x55a31827bc2b in pfs_spawn_thread /experiment/mariadb-server/storage/perfschema/pfs.cc:2201

    #13 0x7f4812443258 in start_thread (/usr/lib/libpthread.so.0+0x9258)

    #14 0x7f4811fee5e2 in __GI___clone (/usr/lib/libc.so.6+0xfe5e2)

0x6190000d6d60 is located 480 bytes inside of 1152-byte region [0x6190000d6b80,0x6190000d7000)

allocated by thread T14 here:

    #0 0x7f4812ad5279 in __interceptor_malloc /build/gcc/src/gcc/libsanitizer/asan/asan_malloc_linux.cpp:145

    #1 0x55a3185c76c0 in ut_allocator<unsigned char, true>::allocate(unsigned long, unsigned char const*, unsigned int, bool, bool) /experiment/mariadb-server/storage/innobase/include/ut0new.h:375

    #2 0x55a3185c76c0 in mem_heap_create_block_func(mem_block_info_t*, unsigned long, unsigned long) /experiment/mariadb-server/storage/innobase/mem/mem0mem.cc:277

    #3 0x55a3184da801 in mem_heap_create_func /experiment/mariadb-server/storage/innobase/include/mem0mem.ic:377

    #4 0x55a3184da801 in ha_innobase::prepare_inplace_alter_table(TABLE*, Alter_inplace_info*) /experiment/mariadb-server/storage/innobase/handler/handler0alter.cc:7816

    #5 0x55a3176a67d2 in mysql_inplace_alter_table /experiment/mariadb-server/sql/sql_table.cc:7326

    #6 0x55a3176a67d2 in mysql_alter_table(THD*, st_mysql_const_lex_string const*, st_mysql_const_lex_string const*, HA_CREATE_INFO*, TABLE_LIST*, Alter_info*, unsigned int, st_order*, bool, bool) /experiment/mariadb-server/sql/sql_table.cc:10205

    #7 0x55a3177fcf99 in Sql_cmd_alter_table::execute(THD*) /experiment/mariadb-server/sql/sql_alter.cc:550

    #8 0x55a31741717f in mysql_execute_command(THD*, bool) /experiment/mariadb-server/sql/sql_parse.cc:5997

    #9 0x55a3174245a0 in mysql_parse(THD*, char*, unsigned int, Parser_state*) /experiment/mariadb-server/sql/sql_parse.cc:8030

    #10 0x55a31742a60b in dispatch_command(enum_server_command, THD*, char*, unsigned int, bool) /experiment/mariadb-server/sql/sql_parse.cc:1896

    #11 0x55a31742f73c in do_command(THD*, bool) /experiment/mariadb-server/sql/sql_parse.cc:1404

    #12 0x55a3177eae56 in do_handle_one_connection(CONNECT*, bool) /experiment/mariadb-server/sql/sql_connect.cc:1418

    #13 0x55a3177eb33c in handle_one_connection /experiment/mariadb-server/sql/sql_connect.cc:1312

    #14 0x55a31827bc2b in pfs_spawn_thread /experiment/mariadb-server/storage/perfschema/pfs.cc:2201

    #15 0x7f4812443258 in start_thread (/usr/lib/libpthread.so.0+0x9258)

Thread T14 created by T0 here:

    #0 0x7f4812a76fa7 in __interceptor_pthread_create /build/gcc/src/gcc/libsanitizer/asan/asan_interceptors.cpp:216

    #1 0x55a31827bea9 in my_thread_create /experiment/mariadb-server/storage/perfschema/my_thread.h:48

    #2 0x55a31827bea9 in pfs_spawn_thread_v1 /experiment/mariadb-server/storage/perfschema/pfs.cc:2252

    #3 0x55a3170ecb3c in inline_mysql_thread_create /experiment/mariadb-server/include/mysql/psi/mysql_thread.h:1139

    #4 0x55a3170ecb3c in create_thread_to_handle_connection(CONNECT*) /experiment/mariadb-server/sql/mysqld.cc:5934

    #5 0x55a3170f87b6 in handle_accepted_socket(st_mysql_socket, st_mysql_socket) /experiment/mariadb-server/sql/mysqld.cc:6055

    #6 0x55a3170f936f in handle_connections_sockets() /experiment/mariadb-server/sql/mysqld.cc:6179

    #7 0x55a3170fca52 in mysqld_main(int, char**) /experiment/mariadb-server/sql/mysqld.cc:5829

    #8 0x7f4811f17b24 in __libc_start_main (/usr/lib/libc.so.6+0x27b24)

SUMMARY: AddressSanitizer: use-after-poison /experiment/mariadb-server/sql/field.h:1395 in prepare_inplace_add_virtual

Shadow bytes around the buggy address:

  0x0c3280012d50: f7 f7 fa fa fa fa fa fa fa fa fa fa fa fa fa fa

  0x0c3280012d60: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa

  0x0c3280012d70: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

  0x0c3280012d80: f7 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

  0x0c3280012d90: 00 00 00 00 00 00 f7 00 00 00 00 00 00 00 00 00

=>0x0c3280012da0: 00 00 00 00 00 00 00 00 00 00 00 f7[f7]f7 f7 f7

  0x0c3280012db0: f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7

  0x0c3280012dc0: f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7

  0x0c3280012dd0: f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7

  0x0c3280012de0: f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7

  0x0c3280012df0: f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7

Shadow byte legend (one shadow byte represents 8 application bytes):

  Addressable:           00

  Partially addressable: 01 02 03 04 05 06 07 

  Heap left redzone:       fa

  Freed heap region:       fd

  Stack left redzone:      f1

  Stack mid redzone:       f2

  Stack right redzone:     f3

  Stack after return:      f5

  Stack use after scope:   f8

  Global redzone:          f9

  Global init order:       f6

  Poisoned by user:        f7

  Container overflow:      fc

  Array cookie:            ac

  Intra object redzone:    bb

  ASan internal:           fe

  Left alloca redzone:     ca

  Right alloca redzone:    cb

  Shadow gap:              cc

==2119277==ABORTING

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