The problem with this is how clamd scans nested mime messages.  If fed a
deeply recursive message it takes an huge amount of RAM to process.  It
appears that some later CVS snapshot handle this better than .70rc does and
so I'm be upgrading to one of them shortly.  However, even under the
snapshots, clamd still uses alot of RAM (several 100 MBs.)  If more than
a few of these hit a busy server, even a well sized busy server, that
server is history.  There are some hackish methods around this like putting
ulimits on clamd or using out of band monitoring to kill it when it gets
too big.  However, I think clamd would bennefit from two additional
features.  

1) Enable Excessive Mime Recursion detection.  If is more than a what, 20
deep, it's not legit.  (These loops I'm seeing go upwards of 4000 parts.)

2) Enable Configurable Memory cap to prevent DoS'ing the local box.
Hopefully as graceful as possible.  Perhaps could be configured to fail
hard or soft. 

-- 
Kelsey Cummings - [EMAIL PROTECTED]           sonic.net, inc.
System Administrator                      2260 Apollo Way
707.522.1000 (Voice)                      Santa Rosa, CA 95407
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