`clickhouse-server.err.log`:
```
2021.04.03 20:00:30.453884 [ 7949 ] {} <Error> ServerErrorHandler: Poco::Exception. Code: 1000, e.code() = 107, e.displayText() = Net Exception: Socket is not connected, Stack trace (when copying this message, always include the lines below):

0. Poco::Net::SocketImpl::error(int, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&) @ 0x11f7dc4e in /usr/bin/clickhouse
1. Poco::Net::SocketImpl::peerAddress() @ 0x11f7fec6 in /usr/bin/clickhouse
2. DB::ReadBufferFromPocoSocket::ReadBufferFromPocoSocket(Poco::Net::Socket&, unsigned long) @ 0xeb536fd in /usr/bin/clickhouse
3. DB::TCPHandler::runImpl() @ 0xf8be39e in /usr/bin/clickhouse
4. DB::TCPHandler::run() @ 0xf8d1529 in /usr/bin/clickhouse
5. Poco::Net::TCPServerConnection::start() @ 0x11f84caf in /usr/bin/clickhouse
6. Poco::Net::TCPServerDispatcher::run() @ 0x11f866c1 in /usr/bin/clickhouse
7. Poco::PooledThread::run() @ 0x120bcde9 in /usr/bin/clickhouse
8. Poco::ThreadImpl::runnableEntry(void*) @ 0x120b8c4a in /usr/bin/clickhouse
9. start_thread @ 0x8fb7 in /usr/lib/x86_64-linux-gnu/libpthread-2.29.so
10. __clone @ 0xfa1af in /usr/lib/x86_64-linux-gnu/libc-2.29.so
 (version 21.3.4.25 (official build))
2021.04.03 20:00:30.456028 [ 25948 ] {} <Fatal> BaseDaemon: ########################################
2021.04.03 20:00:30.456058 [ 25948 ] {} <Fatal> BaseDaemon: (version 21.3.4.25 (official build), build id: 23EA76BDD7B9132C8FB55EC397DB8BAFBEB73C2B) (from thread 7949) (no query) Received signal Segmentation fault (11)
2021.04.03 20:00:30.456081 [ 25948 ] {} <Fatal> BaseDaemon: Address: 0x8 Access: read. Address not mapped to object.
2021.04.03 20:00:30.456092 [ 25948 ] {} <Fatal> BaseDaemon: Stack trace: 0xf8baaa9 0xf8be259 0x11f866d6 0x120bcde9 0x120b8c4a 0x7f267dea1fb7 0x7f267ddd31af
2021.04.03 20:00:30.456116 [ 25948 ] {} <Fatal> BaseDaemon: 1. DB::TCPHandler::~TCPHandler() @ 0xf8baaa9 in /usr/bin/clickhouse
2021.04.03 20:00:30.456135 [ 25948 ] {} <Fatal> BaseDaemon: 2. DB::TCPHandler::~TCPHandler() @ 0xf8be259 in /usr/bin/clickhouse
2021.04.03 20:00:30.456147 [ 25948 ] {} <Fatal> BaseDaemon: 3. Poco::Net::TCPServerDispatcher::run() @ 0x11f866d6 in /usr/bin/clickhouse
2021.04.03 20:00:30.456157 [ 25948 ] {} <Fatal> BaseDaemon: 4. Poco::PooledThread::run() @ 0x120bcde9 in /usr/bin/clickhouse
2021.04.03 20:00:30.456166 [ 25948 ] {} <Fatal> BaseDaemon: 5. Poco::ThreadImpl::runnableEntry(void*) @ 0x120b8c4a in /usr/bin/clickhouse
2021.04.03 20:00:30.456184 [ 25948 ] {} <Fatal> BaseDaemon: 6. start_thread @ 0x8fb7 in /usr/lib/x86_64-linux-gnu/libpthread-2.29.so
2021.04.03 20:00:30.456198 [ 25948 ] {} <Fatal> BaseDaemon: 7. __clone @ 0xfa1af in /usr/lib/x86_64-linux-gnu/libc-2.29.so
2021.04.03 20:00:30.513905 [ 9027 ] {} <Error> ServerErrorHandler: Code: 101, e.displayText() = DB::NetException: Unexpected packet from client, Stack trace (when copying this message, always include the lines below):

0. DB::TCPHandler::receiveHello() @ 0xf8c55a2 in /usr/bin/clickhouse
1. DB::TCPHandler::runImpl() @ 0xf8be569 in /usr/bin/clickhouse
2. DB::TCPHandler::run() @ 0xf8d1529 in /usr/bin/clickhouse
3. Poco::Net::TCPServerConnection::start() @ 0x11f84caf in /usr/bin/clickhouse
4. Poco::Net::TCPServerDispatcher::run() @ 0x11f866c1 in /usr/bin/clickhouse
5. Poco::PooledThread::run() @ 0x120bcde9 in /usr/bin/clickhouse
6. Poco::ThreadImpl::runnableEntry(void*) @ 0x120b8c4a in /usr/bin/clickhouse
7. start_thread @ 0x8fb7 in /usr/lib/x86_64-linux-gnu/libpthread-2.29.so
8. __clone @ 0xfa1af in /usr/lib/x86_64-linux-gnu/libc-2.29.so
 (version 21.3.4.25 (official build))
2021.04.03 20:00:30.641530 [ 9027 ] {} <Error> ServerErrorHandler: Code: 101, e.displayText() = DB::NetException: Unexpected packet from client, Stack trace (when copying this message, always include the lines below):

0. DB::TCPHandler::receiveHello() @ 0xf8c55a2 in /usr/bin/clickhouse
1. DB::TCPHandler::runImpl() @ 0xf8be569 in /usr/bin/clickhouse
2. DB::TCPHandler::run() @ 0xf8d1529 in /usr/bin/clickhouse
3. Poco::Net::TCPServerConnection::start() @ 0x11f84caf in /usr/bin/clickhouse
4. Poco::Net::TCPServerDispatcher::run() @ 0x11f866c1 in /usr/bin/clickhouse
5. Poco::PooledThread::run() @ 0x120bcde9 in /usr/bin/clickhouse
6. Poco::ThreadImpl::runnableEntry(void*) @ 0x120b8c4a in /usr/bin/clickhouse
7. start_thread @ 0x8fb7 in /usr/lib/x86_64-linux-gnu/libpthread-2.29.so
8. __clone @ 0xfa1af in /usr/lib/x86_64-linux-gnu/libc-2.29.so
 (version 21.3.4.25 (official build))
2021.04.03 20:00:31.130743 [ 25948 ] {} <Fatal> BaseDaemon: Checksum of the binary: 2CFBBE6A99CCD7B1089118797E40A0C1, integrity check passed.
2021.04.03 20:00:50.479809 [ 7875 ] {} <Fatal> Application: Child process was terminated by signal 11.
```

`clickhouse-server.log`:
```
2021.04.03 20:00:30.451303 [ 7949 ] {} <Trace> TCPHandlerFactory: TCP Request. Address: [::ffff:94.232.41.116]:56733
2021.04.03 20:00:30.453884 [ 7949 ] {} <Error> ServerErrorHandler: Poco::Exception. Code: 1000, e.code() = 107, e.displayText() = Net Exception: Socket is not connected, Stack trace (when copying this message, always include the lines below):

0. Poco::Net::SocketImpl::error(int, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&) @ 0x11f7dc4e in /usr/bin/clickhouse
1. Poco::Net::SocketImpl::peerAddress() @ 0x11f7fec6 in /usr/bin/clickhouse
2. DB::ReadBufferFromPocoSocket::ReadBufferFromPocoSocket(Poco::Net::Socket&, unsigned long) @ 0xeb536fd in /usr/bin/clickhouse
3. DB::TCPHandler::runImpl() @ 0xf8be39e in /usr/bin/clickhouse
4. DB::TCPHandler::run() @ 0xf8d1529 in /usr/bin/clickhouse
5. Poco::Net::TCPServerConnection::start() @ 0x11f84caf in /usr/bin/clickhouse
6. Poco::Net::TCPServerDispatcher::run() @ 0x11f866c1 in /usr/bin/clickhouse
7. Poco::PooledThread::run() @ 0x120bcde9 in /usr/bin/clickhouse
8. Poco::ThreadImpl::runnableEntry(void*) @ 0x120b8c4a in /usr/bin/clickhouse
9. start_thread @ 0x8fb7 in /usr/lib/x86_64-linux-gnu/libpthread-2.29.so
10. __clone @ 0xfa1af in /usr/lib/x86_64-linux-gnu/libc-2.29.so
 (version 21.3.4.25 (official build))
2021.04.03 20:00:30.454286 [ 7877 ] {} <Trace> BaseDaemon: Received signal 11
2021.04.03 20:00:30.456028 [ 25948 ] {} <Fatal> BaseDaemon: ########################################
2021.04.03 20:00:30.456058 [ 25948 ] {} <Fatal> BaseDaemon: (version 21.3.4.25 (official build), build id: 23EA76BDD7B9132C8FB55EC397DB8BAFBEB73C2B) (from thread 7949) (no query) Received signal Segmentation fault (11)
2021.04.03 20:00:30.456081 [ 25948 ] {} <Fatal> BaseDaemon: Address: 0x8 Access: read. Address not mapped to object.
2021.04.03 20:00:30.456092 [ 25948 ] {} <Fatal> BaseDaemon: Stack trace: 0xf8baaa9 0xf8be259 0x11f866d6 0x120bcde9 0x120b8c4a 0x7f267dea1fb7 0x7f267ddd31af
2021.04.03 20:00:30.456116 [ 25948 ] {} <Fatal> BaseDaemon: 1. DB::TCPHandler::~TCPHandler() @ 0xf8baaa9 in /usr/bin/clickhouse
2021.04.03 20:00:30.456135 [ 25948 ] {} <Fatal> BaseDaemon: 2. DB::TCPHandler::~TCPHandler() @ 0xf8be259 in /usr/bin/clickhouse
2021.04.03 20:00:30.456147 [ 25948 ] {} <Fatal> BaseDaemon: 3. Poco::Net::TCPServerDispatcher::run() @ 0x11f866d6 in /usr/bin/clickhouse
2021.04.03 20:00:30.456157 [ 25948 ] {} <Fatal> BaseDaemon: 4. Poco::PooledThread::run() @ 0x120bcde9 in /usr/bin/clickhouse
2021.04.03 20:00:30.456166 [ 25948 ] {} <Fatal> BaseDaemon: 5. Poco::ThreadImpl::runnableEntry(void*) @ 0x120b8c4a in /usr/bin/clickhouse
2021.04.03 20:00:30.456184 [ 25948 ] {} <Fatal> BaseDaemon: 6. start_thread @ 0x8fb7 in /usr/lib/x86_64-linux-gnu/libpthread-2.29.so
2021.04.03 20:00:30.456198 [ 25948 ] {} <Fatal> BaseDaemon: 7. __clone @ 0xfa1af in /usr/lib/x86_64-linux-gnu/libc-2.29.so
2021.04.03 20:00:30.511549 [ 7885 ] {} <Trace> default.players_performance: Found 2 old parts to remove.
2021.04.03 20:00:30.511568 [ 7885 ] {} <Debug> default.players_performance: Removing part from filesystem 202104_31615436_31622799_6845
2021.04.03 20:00:30.511901 [ 7885 ] {} <Debug> default.players_performance: Removing part from filesystem 202104_31622800_31622800_0
2021.04.03 20:00:30.513751 [ 9027 ] {} <Trace> TCPHandlerFactory: TCP Request. Address: [::ffff:94.232.41.116]:56952
2021.04.03 20:00:30.513905 [ 9027 ] {} <Error> ServerErrorHandler: Code: 101, e.displayText() = DB::NetException: Unexpected packet from client, Stack trace (when copying this message, always include the lines below):

0. DB::TCPHandler::receiveHello() @ 0xf8c55a2 in /usr/bin/clickhouse
1. DB::TCPHandler::runImpl() @ 0xf8be569 in /usr/bin/clickhouse
2. DB::TCPHandler::run() @ 0xf8d1529 in /usr/bin/clickhouse
3. Poco::Net::TCPServerConnection::start() @ 0x11f84caf in /usr/bin/clickhouse
4. Poco::Net::TCPServerDispatcher::run() @ 0x11f866c1 in /usr/bin/clickhouse
5. Poco::PooledThread::run() @ 0x120bcde9 in /usr/bin/clickhouse
6. Poco::ThreadImpl::runnableEntry(void*) @ 0x120b8c4a in /usr/bin/clickhouse
7. start_thread @ 0x8fb7 in /usr/lib/x86_64-linux-gnu/libpthread-2.29.so
8. __clone @ 0xfa1af in /usr/lib/x86_64-linux-gnu/libc-2.29.so
 (version 21.3.4.25 (official build))
2021.04.03 20:00:30.641361 [ 9027 ] {} <Trace> TCPHandlerFactory: TCP Request. Address: [::ffff:94.232.41.116]:57431
2021.04.03 20:00:30.641530 [ 9027 ] {} <Error> ServerErrorHandler: Code: 101, e.displayText() = DB::NetException: Unexpected packet from client, Stack trace (when copying this message, always include the lines below):

0. DB::TCPHandler::receiveHello() @ 0xf8c55a2 in /usr/bin/clickhouse
1. DB::TCPHandler::runImpl() @ 0xf8be569 in /usr/bin/clickhouse
2. DB::TCPHandler::run() @ 0xf8d1529 in /usr/bin/clickhouse
3. Poco::Net::TCPServerConnection::start() @ 0x11f84caf in /usr/bin/clickhouse
4. Poco::Net::TCPServerDispatcher::run() @ 0x11f866c1 in /usr/bin/clickhouse
5. Poco::PooledThread::run() @ 0x120bcde9 in /usr/bin/clickhouse
6. Poco::ThreadImpl::runnableEntry(void*) @ 0x120b8c4a in /usr/bin/clickhouse
7. start_thread @ 0x8fb7 in /usr/lib/x86_64-linux-gnu/libpthread-2.29.so
8. __clone @ 0xfa1af in /usr/lib/x86_64-linux-gnu/libc-2.29.so
 (version 21.3.4.25 (official build))
```

I have no idea who is `94.232.41.116` (probably bot) but it looks like he is the reason.
{
    writeVarUInt(Protocol::Server::ProfileInfo, *out);
    info.write(*out);
    out->next();
}
void TCPHandler::sendTotals(const Block & totals)
{
    if (totals)
    {
        initBlockOutput(totals);
        writeVarUInt(Protocol::Server::Totals, *out);
        writeStringBinary("", *out);
        state.block_out->write(totals);
        state.maybe_compressed_out->next();
        out->next();
    }
}
void TCPHandler::sendExtremes(const Block & extremes)
{
    if (extremes)
    {
        initBlockOutput(extremes);
        writeVarUInt(Protocol::Server::Extremes, *out);
        writeStringBinary("", *out);
        state.block_out->write(extremes);
        state.maybe_compressed_out->next();
        out->next();
    }
}
bool TCPHandler::receiveProxyHeader()