MySQL Bugs: #42412: IPv6 connection handling code bugs

Bug #42412	IPv6 connection handling code bugs
Submitted:	28 Jan 2009 10:53	Modified:	1 Sep 2009 10:04
Reporter:	Frazer Clement	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Server: General	Severity:	S3 (Non-critical)
Version:	6.0,5.4	OS:	Any
Assigned to:	Frazer Clement	CPU Architecture:	Any

Description:
1) Code for hostname to address cache in sql/hostname.cc has bug with pointer passed to search method in the ip_to_hostname() function.
This would probably result in a failure to find any address in the cache or a memory fault.  The cache would probably 'leak' entries.

2) Code for server socket binding in mysqld.cc has bug with address list iteration in network_init().  This could result in an infinite loop.

How to repeat:
1) Probably attempt to connect from multiple hostnames, observe effect on hostname cache etc.

2) Configure machine with >2 socket addresses for a given destination address, so that the first 2 will fail to be created with error INVALID_SOCKET.  Start up server.

Suggested fix:
Fix code.

Duplicate of Bug#38247?

A patch for this bug has been committed. After review, it may
be pushed to the relevant source trees for release in the next
version. You can access the patch from:

  http://lists.mysql.com/commits/64281

2984 Frazer Clement	2009-01-28
      Bug#42412 IPv6 connection handling code bugs
      
      Fix some IPv6 connection handling bugs noticed in mysql-5.1-telco-6.4 branch.
      
      Note that committed but unpushed fix to bug 38247 fixes the issue in hostname.cc.

Locally committed a suggested fix for this bug.

Note that this bug touches some of the same issues as bug#38247, though it also fixes a mistake in mysqld.cc.

If/when bug#38247 is approved, it should be back-ported to mysql-5.1-telco-6.4

I'm fine with the patch.

Duplicate of bug#38247 which has been fixed in a number of separate bugs listed under under its report.

Closing.