UBSAN: applying non-zero offset X to null pointer in strings/ctype-utf16.h | my_mb_wc_utf16_quick

SET character_set_connection=utf16;

SELECT '' LIKE '' ESCAPE EXPORT_SET (1,1,1,1,'');

/test/10.6_opt_san/strings/ctype-utf16.h:52:9: runtime error: applying non-zero offset 2 to null pointer

    #0 0x564edccb13f4 in my_mb_wc_utf16_quick /test/10.6_opt_san/strings/ctype-utf16.h:52:9

    #1 0x564edccb805d in my_charlen_utf16 /test/10.6_opt_san/strings/ctype-ucs2.c:1417:10

    #2 0x564edccb1afd in my_ismbchar /test/10.6_opt_san/include/m_ctype.h:1671:20

    #3 0x564edccb1afd in my_numchars_utf16 /test/10.6_opt_san/strings/ctype-ucs2.c:1438:21

    #4 0x564edb606ef6 in fix_escape_item(THD*, Item*, String*, bool, charset_info_st const*, int*) /test/10.6_opt_san/sql/item_cmpfunc.cc:5950:28

    #5 0x564edb60798e in Item_func_like::fix_fields(THD*, Item**) /test/10.6_opt_san/sql/item_cmpfunc.cc:6000:7

    #6 0x564eda3a5757 in Item::fix_fields_if_needed_for_scalar(THD*, Item**) /test/10.6_opt_san/sql/item.h:1193:12

    #7 0x564eda55712d in setup_fields(THD*, Bounds_checked_array<Item*>, List<Item>&, enum_column_usage, List<Item>*, List<Item>*, bool, THD_WHERE) /test/10.6_opt_san/sql/sql_base.cc:7843:15

    #8 0x564eda8b2dd0 in JOIN::prepare(TABLE_LIST*, Item*, unsigned int, st_order*, bool, st_order*, Item*, st_order*, st_select_lex*, st_select_lex_unit*) /test/10.6_opt_san/sql/sql_select.cc:1512:7

    #9 0x564eda8a66b9 in mysql_select(THD*, TABLE_LIST*, List<Item>&, Item*, unsigned int, st_order*, st_order*, Item*, st_order*, unsigned long long, select_result*, st_select_lex_unit*, st_select_lex*) /test/10.6_opt_san/sql/sql_select.cc:5172:21

    #10 0x564eda8a5780 in handle_select(THD*, LEX*, select_result*, unsigned long) /test/10.6_opt_san/sql/sql_select.cc:573:10

    #11 0x564eda7dda1f in execute_sqlcom_select(THD*, TABLE_LIST*) /test/10.6_opt_san/sql/sql_parse.cc:6422:12

    #12 0x564eda7bbbcd in mysql_execute_command(THD*, bool) /test/10.6_opt_san/sql/sql_parse.cc:4013:12

    #13 0x564eda79d6b0 in mysql_parse(THD*, char*, unsigned int, Parser_state*) /test/10.6_opt_san/sql/sql_parse.cc:8200:18

    #14 0x564eda7949c3 in dispatch_command(enum_server_command, THD*, char*, unsigned int, bool) /test/10.6_opt_san/sql/sql_parse.cc:1908:7

    #15 0x564eda79f976 in do_command(THD*, bool) /test/10.6_opt_san/sql/sql_parse.cc:1421:17

    #16 0x564edada637c in do_handle_one_connection(CONNECT*, bool) /test/10.6_opt_san/sql/sql_connect.cc:1386:11

    #17 0x564edada5bca in handle_one_connection /test/10.6_opt_san/sql/sql_connect.cc:1298:5

    #18 0x564eda2e834c in asan_thread_start(void*) asan_interceptors.cpp.o

    #19 0x7f9718e9caa3 in start_thread nptl/pthread_create.c:447:8

    #20 0x7f9718f29c3b in clone3 misc/../sysdeps/unix/sysv/linux/x86_64/clone3.S:78

SUMMARY: UndefinedBehaviorSanitizer: nullptr-with-nonzero-offset /test/10.6_opt_san/strings/ctype-utf16.h:52:9 

Compiled with a recent version of Clang (I used Clang 18.1.3) with LLVM 18. Ubuntu instructions:

  # Note: It is strongly recommended to uninstall all old Clang & LLVM packages (ref  dpkg --list | grep -iE 'clang|llvm'  and use  apt purge  and  dpkg --purge  to remove the packages), before installing Clang/LLVM 18

     sudo apt install clang llvm-18 llvm-18-linker-tools llvm-18-runtime llvm-18-tools llvm-18-dev libstdc++-14-dev llvm-dev

Compiled with: "-DCMAKE_C_COMPILER=/usr/bin/clang -DCMAKE_CXX_COMPILER=/usr/bin/clang++ -DCMAKE_C{,XX}_FLAGS='-march=native -mtune=native'" and:

    -DWITH_ASAN=ON -DWITH_ASAN_SCOPE=ON -DWITH_UBSAN=ON -DWSREP_LIB_WITH_ASAN=ON

Set before execution:

    export UBSAN_OPTIONS=print_stacktrace=1:report_error_type=1   # And you may also want to supress UBSAN startup issues using 'suppressions=UBSAN.filter' in UBSAN_OPTIONS. For an example of UBSAN.filter, which includes current startup issues see: https://github.com/mariadb-corporation/mariadb-qa/blob/master/UBSAN.filter

    Rel    o/d  Build   Commit                                    UniqueID observed             

CS  10.6   dbg  150525  60f046d7e6b0a61f9b0762fe05c4021cff1b79d8  UBSAN|applying non-zero offset X to null pointer|strings/ctype-utf16.h|my_mb_wc_utf16_quick|my_charlen_utf16|my_ismbchar|my_numchars_utf16

CS  10.6   opt  150525  60f046d7e6b0a61f9b0762fe05c4021cff1b79d8  UBSAN|applying non-zero offset X to null pointer|strings/ctype-utf16.h|my_mb_wc_utf16_quick|my_charlen_utf16|my_ismbchar|my_numchars_utf16

CS  10.11  dbg  150525  84dd2437c507ed194da03fe04fea14e261e47bc5  UBSAN|applying non-zero offset X to null pointer|strings/ctype-utf16.h|my_mb_wc_utf16_quick|my_charlen_utf16|my_ismbchar|my_numchars_utf16

CS  10.11  opt  150525  84dd2437c507ed194da03fe04fea14e261e47bc5  UBSAN|applying non-zero offset X to null pointer|strings/ctype-utf16.h|my_mb_wc_utf16_quick|my_charlen_utf16|my_ismbchar|my_numchars_utf16

CS  11.4   dbg  150525  da5a4d05b9da58705498a42b6ffa5d9211f446af  UBSAN|applying non-zero offset X to null pointer|strings/ctype-utf16.h|my_mb_wc_utf16_quick|my_charlen_utf16|my_ismbchar|my_numchars_utf16

CS  11.4   opt  150525  da5a4d05b9da58705498a42b6ffa5d9211f446af  UBSAN|applying non-zero offset X to null pointer|strings/ctype-utf16.h|my_mb_wc_utf16_quick|my_charlen_utf16|my_ismbchar|my_numchars_utf16

CS  10.6   dbg  150525  865b05bf4acf10e0d4b3359019ed7b2efe0be81d  UBSAN|applying non-zero offset X to null pointer|strings/ctype-utf16.h|my_mb_wc_utf16_quick|my_charlen_utf16|my_ismbchar|my_numchars_utf16

CS  10.6   opt  150525  865b05bf4acf10e0d4b3359019ed7b2efe0be81d  UBSAN|applying non-zero offset X to null pointer|strings/ctype-utf16.h|my_mb_wc_utf16_quick|my_charlen_utf16|my_ismbchar|my_numchars_utf16

CS  12.0   dbg  140525  00a9afb5818433c26537ccaf6b2c59ad493dd473  UBSAN|applying non-zero offset X to null pointer|strings/ctype-utf16.h|my_mb_wc_utf16_quick|my_charlen_utf16|my_ismbchar|my_numchars_utf16

CS  12.0   opt  140525  00a9afb5818433c26537ccaf6b2c59ad493dd473  UBSAN|applying non-zero offset X to null pointer|strings/ctype-utf16.h|my_mb_wc_utf16_quick|my_charlen_utf16|my_ismbchar|my_numchars_utf16

ES  10.6   opt  150525  6111fbaf7bdcb6f1170f556ffd05d6e1a4159f62  UBSAN|applying non-zero offset X to null pointer|strings/ctype-utf16.h|my_mb_wc_utf16_quick|my_charlen_utf16|my_ismbchar|my_numchars_utf16

ES  10.6   dbg  150525  6111fbaf7bdcb6f1170f556ffd05d6e1a4159f62  UBSAN|applying non-zero offset X to null pointer|strings/ctype-utf16.h|my_mb_wc_utf16_quick|my_charlen_utf16|my_ismbchar|my_numchars_utf16

ES  11.4   opt  150525  9cd12544ebfd0d52d2158af66b5aced58121cf1f  UBSAN|applying non-zero offset X to null pointer|strings/ctype-utf16.h|my_mb_wc_utf16_quick|my_charlen_utf16|my_ismbchar|my_numchars_utf16       

ES  11.4   dbg  150525  9cd12544ebfd0d52d2158af66b5aced58121cf1f  UBSAN|applying non-zero offset X to null pointer|strings/ctype-utf16.h|my_mb_wc_utf16_quick|my_charlen_utf16|my_ismbchar|my_numchars_utf16