[Dovecot] Patch to fix leak in imap_refresh_proctitle in beta[5, 6]

[Timo Sirainen]

On Tue, 2010-06-15 at 21:04 -0500, Mike Abbott wrote:
> >> 6   imap                                0x0000000105867333 imap_refresh_proctitle + 218 ->
> >> 7   imap                                0x00000001058666ce cmd_sync_continue + 199 ->
> > 
> > But how does this happen? Did it optimize away some functions
> 
> Yeah optimized out tail-calls, e.g. client_destroy ->
> imap_refresh_proctitle and client_command_free ->
> imap_refresh_proctitle.  I have been digging deeper and found that
> sometimes imap_clients->command_queue->name points to garbage, so
> imap_refresh_proctitle is appending 500MB strings of garbage. 

Is it complete garbage or 0xde character? (Or if you don't use
--with-devel-checks then 0xde shouldn't be appearing.)

>  Combined with a little command pipelining this leads to 4+GB data
> stack pools.  I'll resume digging tomorrow.  Let me know if you need
> any info; I can reproduce this in seconds.

I couldn't find anything obviously wrong in the code.