ASAN heap-use-after-free in copy_if_not_alloced / make_sortkey

CREATE TABLE t1 (a INT, b TIME, c TIME);

INSERT INTO t1 VALUES (NULL,'22:56:45','22:56:45'),(4,'12:51:42','12:51:42');

SELECT REPLACE( BINARY c, a, b ) f FROM t1 GROUP BY f WITH ROLLUP;

# Cleanup

DROP TABLE t1;

==12774==ERROR: AddressSanitizer: heap-use-after-free on address 0x603000056d78 at pc 0x55a62066514f bp 0x7f1fdf3f8aa0 sp 0x7f1fdf3f8a98

READ of size 8 at 0x603000056d78 thread T24

    #0 0x55a62066514e in copy_if_not_alloced(String*, String*, unsigned int) /data/src/10.1/sql/sql_string.cc:915

    #1 0x55a620b784ff in Item_func_replace::val_str(String*) /data/src/10.1/sql/item_strfunc.cc:1197

    #2 0x55a620329b86 in Item::str_result(String*) /data/src/10.1/sql/item.h:1099

    #3 0x55a6209d9798 in make_sortkey /data/src/10.1/sql/filesort.cc:1003

    #4 0x55a6209de6bf in find_all_keys /data/src/10.1/sql/filesort.cc:840

    #5 0x55a6209de6bf in filesort(THD*, TABLE*, st_sort_field*, unsigned int, SQL_SELECT*, unsigned long long, bool, unsigned long long*, unsigned long long*, Filesort_tracker*) /data/src/10.1/sql/filesort.cc:301

    #6 0x55a6205c0ab3 in create_sort_index /data/src/10.1/sql/sql_select.cc:21677

    #7 0x55a6205e7476 in JOIN::exec_inner() /data/src/10.1/sql/sql_select.cc:3245

    #8 0x55a6205e8bd2 in JOIN::exec() /data/src/10.1/sql/sql_select.cc:2562

    #9 0x55a6205dd425 in mysql_select(THD*, Item***, TABLE_LIST*, unsigned int, List<Item>&, Item*, unsigned int, st_order*, st_order*, Item*, st_order*, unsigned long long, select_result*, st_select_lex_unit*, st_select_lex*) /data/src/10.1/sql/sql_select.cc:3499

    #10 0x55a6205ddc13 in handle_select(THD*, LEX*, select_result*, unsigned long) /data/src/10.1/sql/sql_select.cc:388

    #11 0x55a6204acfe6 in execute_sqlcom_select /data/src/10.1/sql/sql_parse.cc:5941

    #12 0x55a6204c7404 in mysql_execute_command(THD*) /data/src/10.1/sql/sql_parse.cc:3038

    #13 0x55a6204dec7d in mysql_parse(THD*, char*, unsigned int, Parser_state*) /data/src/10.1/sql/sql_parse.cc:7459

    #14 0x55a6204e5a1d in dispatch_command(enum_server_command, THD*, char*, unsigned int) /data/src/10.1/sql/sql_parse.cc:1499

    #15 0x55a6204ec16e in do_command(THD*) /data/src/10.1/sql/sql_parse.cc:1131

    #16 0x55a620797334 in do_handle_one_connection(THD*) /data/src/10.1/sql/sql_connect.cc:1330

    #17 0x55a620797845 in handle_one_connection /data/src/10.1/sql/sql_connect.cc:1242

    #18 0x55a620eed24a in pfs_spawn_thread /data/src/10.1/storage/perfschema/pfs.cc:1861

    #19 0x7f2001280493 in start_thread (/lib/x86_64-linux-gnu/libpthread.so.0+0x7493)

    #20 0x7f1fff21b93e in __clone (/lib/x86_64-linux-gnu/libc.so.6+0xe893e)

0x603000056d78 is located 8 bytes inside of 24-byte region [0x603000056d70,0x603000056d88)

freed by thread T24 here:

    #0 0x7f20014ea9f6 in __interceptor_realloc (/usr/lib/x86_64-linux-gnu/libasan.so.1+0x549f6)

    #1 0x55a62180aea5 in my_realloc /data/src/10.1/mysys/my_malloc.c:166

    #2 0x55a62192a4da (/data/bld/10.1-asan/bin/mysqld+0x1d9f4da)

previously allocated by thread T24 here:

    #0 0x7f20014ea73f in malloc (/usr/lib/x86_64-linux-gnu/libasan.so.1+0x5473f)

    #1 0x55a62180a852 in my_malloc /data/src/10.1/mysys/my_malloc.c:101

Thread T24 created by T0 here:

    #0 0x7f20014b9bba in pthread_create (/usr/lib/x86_64-linux-gnu/libasan.so.1+0x23bba)

    #1 0x55a620ef8a5f in spawn_thread_v1 /data/src/10.1/storage/perfschema/pfs.cc:1911

SUMMARY: AddressSanitizer: heap-use-after-free /data/src/10.1/sql/sql_string.cc:915 copy_if_not_alloced(String*, String*, unsigned int)

Shadow bytes around the buggy address:

  0x0c0680002d50: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa

  0x0c0680002d60: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa

  0x0c0680002d70: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa

  0x0c0680002d80: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa

  0x0c0680002d90: fa fa fa fa fa fa fa fa fa fa fa fa 00 00 00 00

=>0x0c0680002da0: fa fa 00 00 00 fa fa fa 00 00 00 fa fa fa fd[fd]

  0x0c0680002db0: fd fa fa fa fd fd fd fa fa fa 00 00 00 fa fa fa

  0x0c0680002dc0: 00 00 00 fa fa fa fd fd fd fa fa fa 00 00 00 00

  0x0c0680002dd0: fa fa fd fd fd fa fa fa fd fd fd fd fa fa fd fd

  0x0c0680002de0: fd fd fa fa fd fd fd fd fa fa fd fd fd fd fa fa

  0x0c0680002df0: fd fd fd fd fa fa fd fd fd fd fa fa fd fd fd fd

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

  Heap right redzone:      fb

  Freed heap region:       fd

  Stack left redzone:      f1

  Stack mid redzone:       f2

  Stack right redzone:     f3

  Stack partial redzone:   f4

  Stack after return:      f5

  Stack use after scope:   f8

  Global redzone:          f9

  Global init order:       f6

  Poisoned by user:        f7

  Contiguous container OOB:fc

  ASan internal:           fe

==12774==ABORTING