[fix](mysql)fix mysql row buffer open_dynamic_mode make _pos pointer …

…out range of _buf (apache#37936)

if we select nested type such as map/array/struct after large string ,
when string type in mysql_row_buf reserve make buffer size is not large
enough , which will lead nested type open_dynamic_mode make _pos pointer
out range of mysql_row_buf, then nested type call push_string, and
reserve() will make heap_buffer_overflow
```
==200769==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x62d0051c12ba at pc 0x55a77788692d bp 0x7fb52f474a30 sp 0x7fb52f4741f8
READ of size 36541 at 0x62d0051c12ba thread T2309 (Pipe_normal [wo)
    #0 0x55a77788692c in __asan_memcpy (/mnt/disk1/wangqiannan/amory/doris/output/be/lib/doris_be+0x60c1c92c) (BuildId: 4513940b6b9e22fa)
    #1 0x55a7a1f622fa in doris::MysqlRowBuffer<false>::reserve(long) /mnt/disk1/wangqiannan/amory/doris/be/src/util/mysql_row_buffer.cpp:140:5
    #2 0x55a7a1f638eb in doris::MysqlRowBuffer<false>::push_string(char const*, long) /mnt/disk1/wangqiannan/amory/doris/be/src/util/mysql_row_buffer.cpp:473:5
    apache#3 0x55a7a21f16eb in doris::Status doris::vectorized::DataTypeMapSerDe::_write_column_to_mysql<false>(doris::vectorized::IColumn const&, doris::MysqlRowBuffer<false>&, int, bool, doris::vectorized::DataTypeSerDe::FormatOptions const&) const /mnt/disk1/wangqiannan/amory/doris/be/src/vec/data_types/serde/data_type_map_serde.cpp:410:21
    apache#4 0x55a7a21e4c1e in doris::vectorized::DataTypeMapSerDe::write_column_to_mysql(doris::vectorized::IColumn const&, doris::MysqlRowBuffer<false>&, int, bool, doris::vectorized::DataTypeSerDe::FormatOptions const&) const /mnt/disk1/wangqiannan/amory/doris/be/src/vec/data_types/serde/data_type_map_serde.cpp:478:12
    apache#5 0x55a7a22070e6 in doris::Status doris::vectorized::DataTypeNullableSerDe::_write_column_to_mysql<false>(doris::vectorized::IColumn const&, doris::MysqlRowBuffer<false>&, int, bool, doris::vectorized::DataTypeSerDe::FormatOptions const&) const /mnt/disk1/wangqiannan/amory/doris/be/src/vec/data_types/serde/data_type_nullable_serde.cpp:300:9
    apache#6 0x55a7a21fbc5e in doris::vectorized::DataTypeNullableSerDe::write_column_to_mysql(doris::vectorized::IColumn const&, doris::MysqlRowBuffer<false>&, int, bool, doris::vectorized::DataTypeSerDe::FormatOptions const&) const /mnt/disk1/wangqiannan/amory/doris/be/src/vec/data_types/serde/data_type_nullable_serde.cpp:317:12
    apache#7 0x55a7c2e97e6c in doris::vectorized::VMysqlResultWriter<false>::write(doris::RuntimeState*, doris::vectorized::Block&) /mnt/disk1/wangqiannan/amory/doris/be/src/vec/sink/vmysql_result_writer.cpp:216:17
    apache#8 0x55a7c8031b83 in doris::pipeline::ResultSinkOperatorX::sink(doris::RuntimeState*, doris::vectorized::Block*, bool) /mnt/disk1/wangqiannan/amory/doris/be/src/pipeline/exec/result_sink_operator.cpp:142:5
    apache#9 0x55a7c99a81d6 in doris::pipeline::PipelineTask::execute(bool*)::$_1::operator()() const /mnt/disk1/wangqiannan/amory/doris/be/src/pipeline/pipeline_task.cpp:361:38
    apache#10 0x55a7c99a4b27 in doris::pipeline::PipelineTask::execute(bool*) /mnt/disk1/wangqiannan/amory/doris/be/src/pipeline/pipeline_task.cpp:364:22
    apache#11 0x55a7c9a23a2b in doris::pipeline::TaskScheduler::_do_work(unsigned long) /mnt/disk1/wangqiannan/amory/doris/be/src/pipeline/task_scheduler.cpp:138:9
    apache#12 0x55a7c9a269ca in doris::pipeline::TaskScheduler::start()::$_0::operator()() const /mnt/disk1/wangqiannan/amory/doris/be/src/pipeline/task_scheduler.cpp:64:9
    apache#13 0x55a7c9a2694e in void std::__invoke_impl<void, doris::pipeline::TaskScheduler::start()::$_0&>(std::__invoke_other, doris::pipeline::TaskScheduler::start()::$_0&) /mnt/disk1/wangqiannan/tool/ldb_toolchain_16/bin/../lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/bits/invoke.h:61:14
    apache#14 0x55a7c9a268ae in std::enable_if<is_invocable_r_v<void, doris::pipeline::TaskScheduler::start()::$_0&>, void>::type std::__invoke_r<void, doris::pipeline::TaskScheduler::start()::$_0&>(doris::pipeline::TaskScheduler::start()::$_0&) /mnt/disk1/wangqiannan/tool/ldb_toolchain_16/bin/../lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/bits/invoke.h:111:2
    apache#15 0x55a7c9a26635 in std::_Function_handler<void (), doris::pipeline::TaskScheduler::start()::$_0>::_M_invoke(std::_Any_data const&) /mnt/disk1/wangqiannan/tool/ldb_toolchain_16/bin/../lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/bits/std_function.h:291:9
    apache#16 0x55a777b226da in std::function<void ()>::operator()() const /mnt/disk1/wangqiannan/tool/ldb_toolchain_16/bin/../lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/bits/std_function.h:560:9
    apache#17 0x55a77e95ec94 in doris::FunctionRunnable::run() /mnt/disk1/wangqiannan/amory/doris/be/src/util/threadpool.cpp:48:27
    apache#18 0x55a77e941015 in doris::ThreadPool::dispatch_thread() /mnt/disk1/wangqiannan/amory/doris/be/src/util/threadpool.cpp:543:24
    apache#19 0x55a77e97eb23 in void std::__invoke_impl<void, void (doris::ThreadPool::*&)(), doris::ThreadPool*&>(std::__invoke_memfun_deref, void (doris::ThreadPool::*&)(), doris::ThreadPool*&) /mnt/disk1/wangqiannan/tool/ldb_toolchain_16/bin/../lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/bits/invoke.h:74:14
    apache#20 0x55a77e97e928 in std::__invoke_result<void (doris::ThreadPool::*&)(), doris::ThreadPool*&>::type std::__invoke<void (doris::ThreadPool::*&)(), doris::ThreadPool*&>(void (doris::ThreadPool::*&)(), doris::ThreadPool*&) /mnt/disk1/wangqiannan/tool/ldb_toolchain_16/bin/../lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/bits/invoke.h:96:14
    apache#21 0x55a77e97e860 in void std::_Bind<void (doris::ThreadPool::* (doris::ThreadPool*))()>::__call<void, 0ul>(std::tuple<>&&, std::_Index_tuple<0ul>) /mnt/disk1/wangqiannan/tool/ldb_toolchain_16/bin/../lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/functional:420:11
    apache#22 0x55a77e97e655 in void std::_Bind<void (doris::ThreadPool::* (doris::ThreadPool*))()>::operator()<void>() /mnt/disk1/wangqiannan/tool/ldb_toolchain_16/bin/../lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/functional:503:17
    apache#23 0x55a77e97e54e in void std::__invoke_impl<void, std::_Bind<void (doris::ThreadPool::* (doris::ThreadPool*))()>&>(std::__invoke_other, std::_Bind<void (doris::ThreadPool::* (doris::ThreadPool*))()>&) /mnt/disk1/wangqiannan/tool/ldb_toolchain_16/bin/../lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/bits/invoke.h:61:14
    apache#24 0x55a77e97e48e in std::enable_if<is_invocable_r_v<void, std::_Bind<void (doris::ThreadPool::* (doris::ThreadPool*))()>&>, void>::type std::__invoke_r<void, std::_Bind<void (doris::ThreadPool::* (doris::ThreadPool*))()>&>(std::_Bind<void (doris::ThreadPool::* (doris::ThreadPool*))()>&) /mnt/disk1/wangqiannan/tool/ldb_toolchain_16/bin/../lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/bits/invoke.h:111:2
    apache#25 0x55a77e97dd85 in std::_Function_handler<void (), std::_Bind<void (doris::ThreadPool::* (doris::ThreadPool*))()>>::_M_invoke(std::_Any_data const&) /mnt/disk1/wangqiannan/tool/ldb_toolchain_16/bin/../lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/bits/std_function.h:291:9
    apache#26 0x55a777b226da in std::function<void ()>::operator()() const /mnt/disk1/wangqiannan/tool/ldb_toolchain_16/bin/../lib/gcc/x86_64-linux-gnu/11/../../../../include/c++/11/bits/std_function.h:560:9
    apache#27 0x55a77e8fb841 in doris::Thread::supervise_thread(void*) /mnt/disk1/wangqiannan/amory/doris/be/src/util/thread.cpp:498:5
    apache#28 0x7fc1c3a111c9 in start_thread (/lib64/libpthread.so.0+0x81c9) (BuildId: 823fccea3475e5870a4167dfe47df20e53222db0)
    apache#29 0x7fc1c4400e72 in clone (/lib64/libc.so.6+0x39e72) (BuildId: ec3d7025354f1f1985831ff08ef0eb3b50aefbce)

0x62d0051c12ba is located 0 bytes after 36538-byte region [0x62d0051b8400,0x62d0051c12ba)
allocated by thread T2309 (Pipe_normal [wo) here:
    #0 0x55a7778c20bd in operator new[](unsigned long) (/mnt/disk1/wangqiannan/amory/doris/output/be/lib/doris_be+0x60c580bd) (BuildId: 4513940b6b9e22fa)
    #1 0x55a7a1f621c1 in doris::MysqlRowBuffer<false>::reserve(long) /mnt/disk1/wangqiannan/amory/doris/be/src/util/mysql_row_buffer.cpp:137:21
    #2 0x55a7a1f638eb in doris::MysqlRowBuffer<false>::push_string(char const*, long) /mnt/disk1/wangqiannan/amory/doris/be/src/util/mysql_row_buffer.cpp:473:5
    apache#3 0x55a7a1fd0d75 in doris::Status doris::vectorized::DataTypeStringSerDeBase<doris::vectorized::ColumnStr<unsigned int>>::_write_column_to_mysql<false>(doris::vectorized::IColumn const&, doris::MysqlRowBuffer<false>&, int, bool, doris::vectorized::DataTypeSerDe::FormatOptions const&) const /mnt/disk1/wangqiannan/amory/doris/be/src/vec/data_types/serde/data_type_string_serde.h:260:16
    apache#4 0x55a7a1fccc1e in doris::vectorized::DataTypeStringSerDeBase<doris::vectorized::ColumnStr<unsigned int>>::write_column_to_mysql(doris::vectorized::IColumn const&, doris::MysqlRowBuffer<false>&, int, bool, doris::vectorized::DataTypeSerDe::FormatOptions const&) const /mnt/disk1/wangqiannan/amory/doris/be/src/vec/data_types/serde/data_type_string_serde.h:215:16
    apache#5 0x55a7c2e97e6c in doris::vectorized::VMysqlResultWriter<false>::write(doris::RuntimeState*, doris::vectorized::Block&) /mnt/disk1/wangqiannan/amory/doris/be/src/vec/sink/vmysql_result_writer.cpp:216:17
    apache#6 0x55a7c8031b83 in doris::pipeline::ResultSinkOperatorX::sink(doris::RuntimeState*, doris::vectorized::Block*, bool) /mnt/disk1/wangqiannan/amory/doris/be/src/pipeline/exec/result_sink_operator.cpp:142:5
    apache#7 0x55a7c99a81d6 in doris::pipeline::PipelineTask::execute(bool*)::$_1::operator()() const /mnt/disk1/wangqiannan/amory/doris/be/src/pipeline/pipeline_task.cpp:361:38
```

## Proposed changes

Issue Number: close #xxx

<!--Describe your changes.-->

be/src/util/mysql_row_buffer.cpp

@@ -44,6 +44,9 @@ namespace doris {
 static uint8_t NEXT_TWO_BYTE = 252;
 static uint8_t NEXT_THREE_BYTE = 253;
 static uint8_t NEXT_EIGHT_BYTE = 254;
+// the EXTRA_RESERVE_BYTE wanner to make sure _pos pointer is always in _buf memory
+// used in reserve() for allocate current buffer
+static size_t EXTRA_RESERVE_BYTE = 16;
 
 // the first byte:
 // <= 250: length
@@ -133,7 +136,7 @@ int MysqlRowBuffer<is_binary_format>::reserve(int64_t size) {
         return 0;
     }
 
-    int64_t alloc_size = std::max(need_size, _buf_size * 2);
+    int64_t alloc_size = std::max(need_size, _buf_size * 2) + EXTRA_RESERVE_BYTE;
     char* new_buf = new char[alloc_size];
 
     size_t offset = _pos - _buf;