从NetCore报错到MySql安全

之前项目在测试服务器上的一些接口时不时会报出下面的错误：（采用abp框架）

"socketexception: 你的主机中的软件中止了一个已建立的连接。
stack trace:    at mysqlconnector.protocol.serialization.socketbytehandler.writebytesasync(arraysegment`1 data, iobehavior iobehavior) in c:\projects\mysqlconnector\src\mysqlconnector\protocol\serialization\socketbytehandler.cs:line 90
--- end of stack trace from previous location where exception was thrown ---
   at system.runtime.exceptionservices.exceptiondispatchinfo.throw()
   at system.runtime.compilerservices.taskawaiter.handlenonsuccessanddebuggernotification(task task)
   at mysqlconnector.utilities.valuetaskextensions.<continuewith>d__0`2.movenext() in c:\projects\mysqlconnector\src\mysqlconnector\utilities\valuetaskextensions.cs:line 8
--- end of stack trace from previous location where exception was thrown ---
   at system.runtime.exceptionservices.exceptiondispatchinfo.throw()
   at system.runtime.compilerservices.taskawaiter.handlenonsuccessanddebuggernotification(task task)
   at mysqlconnector.core.serversession.tryasynccontinuation(task`1 task) in c:\projects\mysqlconnector\src\mysqlconnector\core\serversession.cs:line 1225
   at system.threading.tasks.continuationresulttaskfromresulttask`2.innerinvoke()
   at system.threading.executioncontext.run(executioncontext executioncontext, contextcallback callback, object state)
   at system.threading.tasks.task.executewiththreadlocal(task& currenttaskslot)
--- end of stack trace from previous location where exception was thrown ---
   at system.runtime.exceptionservices.exceptiondispatchinfo.throw()
   at system.runtime.compilerservices.taskawaiter.handlenonsuccessanddebuggernotification(task task)
   at mysqlconnector.core.textcommandexecutor.<executereaderasync>d__1.movenext() in c:\projects\mysqlconnector\src\mysqlconnector\core\textcommandexecutor.cs:line 36
--- end of stack trace from previous location where exception was thrown ---
   at system.runtime.exceptionservices.exceptiondispatchinfo.throw()
   at system.runtime.compilerservices.taskawaiter.handlenonsuccessanddebuggernotification(task task)
   at mysql.data.mysqlclient.mysqlcommand.<executenonqueryasync>d__60.movenext() in c:\projects\mysqlconnector\src\mysqlconnector\mysql.data.mysqlclient\mysqlcommand.cs:line 261
--- end of stack trace from previous location where exception was thrown ---
   at system.runtime.exceptionservices.exceptiondispatchinfo.throw()
   at system.runtime.compilerservices.taskawaiter.handlenonsuccessanddebuggernotification(task task)
   at mysql.data.mysqlclient.mysqlcommand.executenonquery() in c:\projects\mysqlconnector\src\mysqlconnector\mysql.data.mysqlclient\mysqlcommand.cs:line 62
   at mysql.data.mysqlclient.mysqltransaction.dispose(boolean disposing) in c:\projects\mysqlconnector\src\mysqlconnector\mysql.data.mysqlclient\mysqltransaction.cs:line 81
   at microsoft.entityframeworkcore.storage.relationaltransaction.dispose()
   at abp.entityframeworkcore.uow.dbcontextefcoretransactionstrategy.dispose(iiocresolver iocresolver)
   at abp.entityframeworkcore.uow.efcoreunitofwork.disposeuow()
   at abp.domain.uow.unitofworkbase.dispose()
   at abp.aspnetcore.mvc.uow.abpuowactionfilter.<onactionexecutionasync>d__4.movenext()
--- end of stack trace from previous location where exception was thrown ---
   at system.runtime.exceptionservices.exceptiondispatchinfo.throw()
   at system.runtime.compilerservices.taskawaiter.handlenonsuccessanddebuggernotification(task task)
   at microsoft.aspnetcore.mvc.internal.controlleractioninvoker.<invokenextactionfilterasync>d__10.movenext()
--- end of stack trace from previous location where exception was thrown ---
   at system.runtime.exceptionservices.exceptiondispatchinfo.throw()
   at microsoft.aspnetcore.mvc.internal.controlleractioninvoker.rethrow(actionexecutedcontext context)
   at microsoft.aspnetcore.mvc.internal.controlleractioninvoker.next(state& next, scope& scope, object& state, boolean& iscompleted)
   at microsoft.aspnetcore.mvc.internal.controlleractioninvoker.<invokeinnerfilterasync>d__13.movenext()
--- end of stack trace from previous location where exception was thrown ---
   at system.runtime.exceptionservices.exceptiondispatchinfo.throw()
   at system.runtime.compilerservices.taskawaiter.handlenonsuccessanddebuggernotification(task task)
   at microsoft.aspnetcore.mvc.internal.resourceinvoker.<invokenextexceptionfilterasync>d__24.movenext()
"

view code

mysql.data.mysqlclient.mysqlexception (0x80004005): failed to read the result set. 
---> system.io.endofstreamexception: expected to read 4 header bytes but only received 0.
   at system.runtime.exceptionservices.exceptiondispatchinfo.throw()
   at system.runtime.compilerservices.taskawaiter.handlenonsuccessanddebuggernotification(task task)
   at mysqlconnector.protocol.serialization.protocolutility.doreadpayloadasync(bufferedbytereader bufferedbytereader, ibytehandler bytehandler, func`1 getnextsequencenumber, arraysegmentholder`1 previouspayloads, protocolerrorbehavior protocolerrorbehavior, iobehavior iobehavior) in c:\projects\mysqlconnector\src\mysqlconnector\protocol\serialization\protocolutility.cs:line 462
   at mysqlconnector.protocol.serialization.standardpayloadhandler.readpayloadasync(arraysegmentholder`1 cache, protocolerrorbehavior protocolerrorbehavior, iobehavior iobehavior) in c:\projects\mysqlconnector\src\mysqlconnector\protocol\serialization\standardpayloadhandler.cs:line 37
   at mysqlconnector.core.serversession.receivereplyasync(iobehavior iobehavior, cancellationtoken cancellationtoken) in c:\projects\mysqlconnector\src\mysqlconnector\core\serversession.cs:line 645
--- end of stack trace from previous location where exception was thrown ---
   at system.runtime.exceptionservices.exceptiondispatchinfo.throw()
   at system.runtime.compilerservices.taskawaiter.handlenonsuccessanddebuggernotification(task task)
   at mysqlconnector.core.serversession.tryasynccontinuation(task`1 task) in c:\projects\mysqlconnector\src\mysqlconnector\core\serversession.cs:line 1230
   at system.threading.tasks.continuationresulttaskfromresulttask`2.innerinvoke()
   at system.threading.executioncontext.run(executioncontext executioncontext, contextcallback callback, object state)
   at system.threading.tasks.task.executewiththreadlocal(task& currenttaskslot)
--- end of stack trace from previous location where exception was thrown ---

view code

然后我使用swagger+miniprofiler，查看生成的sql语句

 

查看mysql错误日志：

aborted connection 422 to db: '数据库名称' user: 'root' host: 'localhost' (got a packet bigger than 'max_allowed_packet' bytes)

可能因为传输的数据过大，而mysql的max_allowed_packet默认为1024b，导致sql执行不成功。

然后将mysql配置文件中的max_allowed_packet值改为max_allowed_packet = 4m

重启mysql，问题解决。

 

然而过了一段时间，同样的报错又出现了，首先看了下max_allowed_packet的值，果然max_allowed_packet又被修改为了1024b，查看命令如下：

show variables like '%max_allowed_packet%';

 

然后询问同事，他们说并没有动数据库，上网查了下说是有可能是被攻击了。

于是我开启了mysql的日志，命令如下：

set global general_log=on;

 

在日志里看到了被修改信息，然后看了下ip~~~

还发现了几个新增用户tvt，把它删掉：

 

查看mysql用户命令如下：

select * from mysql.user

 

目前解决方法是，加强密码，限制远程连接ip：把上图的% 改为指定ip段xxx.xxx.xxx.%，重启mysql。