UBSAN: runtime error: applying zero offset to null pointer in my_strnncollsp_utf8mb3_general_ci and my_strnncollsp_gb2312_chinese_ci on SELECT ... EXTRACTVALUE

CREATE TABLE t (c INT);

SET NAMES gb2312;

INSERT INTO t VALUES (1);

SELECT * FROM t WHERE EXTRACTVALUE (c,'a')='a';

/test/11.8_dbg_san/strings/strcoll.inl:324:25: runtime error: applying zero offset to null pointer

    #0 0x55636b8fac01 in my_strnncollsp_gb2312_chinese_ci /test/11.8_dbg_san/strings/strcoll.inl:324:25

    #1 0x55636a099dd1 in Arg_comparator::compare() /test/11.8_dbg_san/sql/item_cmpfunc.h:114:33

    #2 0x55636a099dd1 in Item_func_eq::val_bool() /test/11.8_dbg_san/sql/item_cmpfunc.cc:1881:18

    #3 0x556369309aa6 in evaluate_join_record(JOIN*, st_join_table*, int) /test/11.8_dbg_san/sql/sql_select.cc:24210:25

    #4 0x5563691dd3bf in sub_select(JOIN*, st_join_table*, bool) /test/11.8_dbg_san/sql/sql_select.cc:24109:9

    #5 0x55636926d79c in do_select(JOIN*, Procedure*) /test/11.8_dbg_san/sql/sql_select.cc:23620:14

    #6 0x55636926a0f1 in JOIN::exec_inner() /test/11.8_dbg_san/sql/sql_select.cc:5040:50

    #7 0x556369267a12 in JOIN::exec() /test/11.8_dbg_san/sql/sql_select.cc:4823:8

    #8 0x5563691e1634 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/11.8_dbg_san/sql/sql_select.cc:5356:21

    #9 0x5563691dff12 in handle_select(THD*, LEX*, select_result*, unsigned long long) /test/11.8_dbg_san/sql/sql_select.cc:633:10

    #10 0x5563690b5167 in execute_sqlcom_select(THD*, TABLE_LIST*) /test/11.8_dbg_san/sql/sql_parse.cc:6191:12

    #11 0x5563690a0d39 in mysql_execute_command(THD*, bool) /test/11.8_dbg_san/sql/sql_parse.cc:3980:12

    #12 0x556369070588 in mysql_parse(THD*, char*, unsigned int, Parser_state*) /test/11.8_dbg_san/sql/sql_parse.cc:7915:18

    #13 0x55636906464b in dispatch_command(enum_server_command, THD*, char*, unsigned int, bool) /test/11.8_dbg_san/sql/sql_parse.cc:1903:7

    #14 0x556369072fad in do_command(THD*, bool) /test/11.8_dbg_san/sql/sql_parse.cc:1416:17

    #15 0x55636973676c in do_handle_one_connection(CONNECT*, bool) /test/11.8_dbg_san/sql/sql_connect.cc:1415:11

    #16 0x556369736027 in handle_one_connection /test/11.8_dbg_san/sql/sql_connect.cc:1327:5

    #17 0x556368a75b5c in asan_thread_start(void*) asan_interceptors.cpp.o

    #18 0x1524fdc9ca93 in start_thread nptl/pthread_create.c:447:8

    #19 0x1524fdd29c3b in clone3 misc/../sysdeps/unix/sysv/linux/x86_64/clone3.S:78

SUMMARY: UndefinedBehaviorSanitizer: nullptr-with-offset /test/11.8_dbg_san/strings/strcoll.inl:324:25 

/test/11.8_dbg_san/strings/strcoll.inl:324:25: runtime error: applying zero offset to null pointer

    #0 0x560a2c254c01 in my_strnncollsp_gb2312_chinese_ci /test/11.8_dbg_san/strings/strcoll.inl:324:25

    #1 0x560a2a9f3dd1 in Arg_comparator::compare() /test/11.8_dbg_san/sql/item_cmpfunc.h:114:33

    #2 0x560a2a9f3dd1 in Item_func_eq::val_bool() /test/11.8_dbg_san/sql/item_cmpfunc.cc:1881:18

    #3 0x560a29c63aa6 in evaluate_join_record(JOIN*, st_join_table*, int) /test/11.8_dbg_san/sql/sql_select.cc:24210:25

    #4 0x560a29b373bf in sub_select(JOIN*, st_join_table*, bool) /test/11.8_dbg_san/sql/sql_select.cc:24109:9

    #5 0x560a29bc779c in do_select(JOIN*, Procedure*) /test/11.8_dbg_san/sql/sql_select.cc:23620:14

    #6 0x560a29bc40f1 in JOIN::exec_inner() /test/11.8_dbg_san/sql/sql_select.cc:5040:50

    #7 0x560a29bc1a12 in JOIN::exec() /test/11.8_dbg_san/sql/sql_select.cc:4823:8

    #8 0x560a29b3b634 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/11.8_dbg_san/sql/sql_select.cc:5356:21

    #9 0x560a29b39f12 in handle_select(THD*, LEX*, select_result*, unsigned long long) /test/11.8_dbg_san/sql/sql_select.cc:633:10

    #10 0x560a29a0f167 in execute_sqlcom_select(THD*, TABLE_LIST*) /test/11.8_dbg_san/sql/sql_parse.cc:6191:12

    #11 0x560a299fad39 in mysql_execute_command(THD*, bool) /test/11.8_dbg_san/sql/sql_parse.cc:3980:12

    #12 0x560a299ca588 in mysql_parse(THD*, char*, unsigned int, Parser_state*) /test/11.8_dbg_san/sql/sql_parse.cc:7915:18

    #13 0x560a299be64b in dispatch_command(enum_server_command, THD*, char*, unsigned int, bool) /test/11.8_dbg_san/sql/sql_parse.cc:1903:7

    #14 0x560a299ccfad in do_command(THD*, bool) /test/11.8_dbg_san/sql/sql_parse.cc:1416:17

    #15 0x560a2a09076c in do_handle_one_connection(CONNECT*, bool) /test/11.8_dbg_san/sql/sql_connect.cc:1415:11

    #16 0x560a2a090027 in handle_one_connection /test/11.8_dbg_san/sql/sql_connect.cc:1327:5

    #17 0x560a293cfb5c in asan_thread_start(void*) asan_interceptors.cpp.o

    #18 0x14cd7c29ca93 in start_thread nptl/pthread_create.c:447:8

    #19 0x14cd7c329c3b in clone3 misc/../sysdeps/unix/sysv/linux/x86_64/clone3.S:78

SUMMARY: UndefinedBehaviorSanitizer: nullptr-with-offset /test/11.8_dbg_san/strings/strcoll.inl:324:25 

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

     # Note: llvm-17-linker-tools installs /usr/lib/llvm-17/lib/LLVMgold.so, which is needed for compilation, and LLVMgold.so is no longer included in 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 llvm-17-linker-tools

     sudo ln -s /usr/lib/llvm-17/lib/LLVMgold.so /usr/lib/llvm-18/lib/LLVMgold.so

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

    export ASAN_OPTIONS=quarantine_size_mb=512:atexit=0:detect_invalid_pointer_pairs=3:dump_instruction_bytes=1:abort_on_error=1:allocator_may_return_null=1