misc/73105: Sendmail on stock FreeBSD 4.10 goes in infinite loop while sending bulk email

[Ron van Daal]

>Number:         73105
>Category:       misc
>Synopsis:       Sendmail on stock FreeBSD 4.10 goes in infinite loop while sending bulk email
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Mon Oct 25 08:40:28 GMT 2004
>Closed-Date:
>Last-Modified:
>Originator:     Ron van Daal
>Release:        4.10-RELEASE
>Organization:
>Environment:
FreeBSD z.xxx.com 4.10-RELEASE-p2 FreeBSD 4.10-RELEASE-p2 #0: Wed Sep 15 01:31:44 CEST 2004     root at z.xxx.com:/usr/obj/usr/src/sys/ZARA  i386
>Description:
Sendmail 8.12.11 (FreeBSD 4.10 distribution) seems to get in an internal loop while sending bulk mail (no spam) delivered at the localhost smtp port. This results in a system load >12 causing the mailservice to stop accepting mail on it's smtp port. Sendmail generates the following syslog error hundreds of times a second: 
"sm-mta[54905]: STARTTLS: read error=generic SSL error (0)". Sendmail stops working and syslogd takes all CPU. I noticed this problem when Apache/PHP couldn't connect to MySQLd running on the same host. For some reason the Sendmail problem caused MySQLd to generate hundreds of MySQLd processes (with linux-threads) - I believe there were UNIX socket problems (?)
>How-To-Repeat:
Repeat the problem by installing FreeBSD 4.10, updating it to CVS and delivering bulk mail (in our case 1000 pcs.) to the localhost smtp port. Sendmail should be giving the SSL error after a while but will still be delivering e-mail. Eventually sendmail locks up.

>Fix:
There is a defining _FFR_DEAL_WITH_ERROR_SSL for the site.config.m4 file which should prevent Sendmail from going into infinite loops. I think it's necessary (or at least it would be very convenient) to include this in the default Sendmail/FreeBSD configuration.

>Release-Note:
>Audit-Trail:
>Unformatted: