Hi,
Problem description:
recently I've noticed some strange fetchmail (+sendmail) behaviour,
causing a Sendmail sessions not to close (and therefor causing a very
strong increase in memory usage, until Fetchmail is shut down) when an
email is sent with > 32k in the header (in this specific case it
contained 32kb of email addresses in the To: line).
System:
- Sendmail 8.11.0 (RedHat RPM, default RH7)
- Fetchmail all versions up to 5.6.6 (tried various 5.6.x)
How to reproduce:
Fetchmail is run with the "-d 30" parameters, no specific other parms
in the .fetchmailrc config file except 4 pop3 accounts. Send yourself an
email with > 32kb in the email headers, fetch as usual.
What happens:
Fetchmail connects to the pop3 server and grabs the email like
expected, it then tries to feed it to the locally running Sendmail
process where the mail is not accepted (sendmail returns an error).
The problem then occurring is that the Sendmail connection is *not*
closed (sendmail eventually does go to CLOSE_WAIT), including connections
caused by other fetchmail connections. The amount of open Sendmail
connections will keep increasing until the system eventually is unable
to handle the memory usage.
On my system after running fetchmail for about half a day I had over
250 open sendmail connections. Not good on a single user system.
Vague rumour:
A colleague of mine is running Fetchmail under Debian and reported
having an enormous amount of pop3 connections open to the mailserver
with the faulty email. This might be related.
regards,
Remco
--
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