MySQL Bugs: #31419: mysql-proxy abort with assertion failed: (*

Bug #31419	mysql-proxy abort with assertion failed: (*_off < packet->len)
Submitted:	5 Oct 2007 12:59	Modified:	21 Jan 2009 12:17
Reporter:	Carlos Silva e Silva	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Proxy: Core	Severity:	S1 (Critical)
Version:	SVN Revision 258	OS:	Any (Gentoo Linux)
Assigned to:	MC Brown	CPU Architecture:	Any
Tags:	assertion failed network-mysqld-proto

Description:
mysql-proxy crashes with:

file network-mysqld-proto.c: line 106 (network_mysqld_proto_get_int_len): assertion failed: (*_off < packet->len)
Aborted

My mainly problem is using the mysql-proxy to filter out connections from the development team and having different programs connecting to the server.

No one is using the mysql-3.23 client direct but this client gave me the same error from "Delphi for PHP"

--

Carlos Augusto

How to repeat:
Connect using a mysql 3.23 client

Thank you for taking the time to write to us, but this is not a bug. Please double-check the documentation available at  
http://dev.mysql.com/doc/refman/5.1/en/mysql-proxy-platforms.html

MySQL Proxy, by design, is not compatible with the old client/server protocol. You need at least MySQL 4.1 to use MySQL Proxy.

Actually I disagree with this, crashing is never good - the proxy should simply return an error to the client that is trying to connect, that the client version is not supported (or some other similar error). 

This opens up a denial of service opportunity when using the proxy in production. 

Fix this please.

Actually, the proxy is not crashing. It is aborting, which is a voluntary action.
Anyway, I agree that it should handle this error more gracefully.

This is exactly my problem, I don't use any 3.xx clients but in a number of occasions the proxy is aborting and I don't want to go messing around with the core code.

Similar error if proxy backends 3.23 server:

$mysql-proxy --proxy-backend-addresses=127.0.0.1:3332
file network-mysqld-proto.c: line 136 (network_mysqld_proto_get_string_len): assertion failed: (*_off < packet->len)

Bug #42128 was marked as duplicate of this one.

This has been fixed on the latest revision from launchpad

https://launchpad.net/mysql-proxy/+announcement/1798

See http://forge.mysql.com/wiki/MySQL_Proxy_Compiling  for compiling
help.

A note has been added to the 0.7.0 changelog: 

Security Enhancement: Accessing mysql-proxy using a client or backend with a MySQL protocol less than MySQL 5.0 would result in mysql-proxy aborting with an assertion. This is because mysql-proxy only supports MySQL Protocol 5.0 or higher. The proxy will now report a fault