[stunnel-users] /var/log/syslog is filling up with stunnel errors

Fri Jun 19 12:52:48 CEST 2020

This is an ongoing problem for me. I've hacked my version of stunnel4-5.30 to include a configuration item for a reconnect timeout when a reset occurs (hard coded default of 500ms so I don't have to touch everything). Without it, syslog just fills up with stunnel messages until /var is full on all my systems. I can send along a diff if anyone wants it, let me know.

Regarding Mr. Ward's reply below. Yes, the connection appears blocked because the remote syslog server is offline for a kernel reboot during this time. The connection does not recover by itself once the remote is back online.

I'll keep investigating as this must be some weird thing with my systems but also may also be due to some bug in stunnel under the right circumstances.

digitek wrote on 5/24/20 6:34 AM:
> Thomas Ward wrote on 5/23/20 7:09 PM:
>> This is indicative of the remote server not running on the right ports normally or actively blocking you, given the "Connection Refused" errors.� Verify your system stunnel is on actually can connect to the specified IP and port combo independently of stunnel to start with.
>>
> 
> I noticed this morning there are possible malloc issues appearing in syslog as well. Is this perhaps related? This is log from a postgres stunnel client.
> 
> May 24 06:27:12 copper stunnel: LOG5[1022959]: Service [postgres_tunnel] connected remote server from 192.168.1.24:41350
> May 24 06:27:12 copper stunnel: LOG5[1022958]: Service [postgres_tunnel] connected remote server from 192.168.1.24:41348
> May 24 06:27:12 copper stunnel: LOG5[1022960]: s_connect: connected 192.168.1.9:15432
> May 24 06:27:12 copper stunnel: LOG5[1022960]: Service [postgres_tunnel] connected remote server from 192.168.1.24:41352
> May 24 06:27:12 copper stunnel: LOG5[1022920]: Connection closed: 3278 byte(s) sent to TLS, 2024 byte(s) sent to socket
> May 24 06:27:12 copper stunnel: LOG4[1022920]: Possible memory leak at ../crypto/bn/bn_lib.c:224: 30007 allocations
> May 24 06:27:12 copper stunnel: LOG5[1022918]: Connection closed: 4519 byte(s) sent to TLS, 1972 byte(s) sent to socket
> May 24 06:27:12 copper stunnel: LOG5[1022919]: Connection closed: 1174 byte(s) sent to TLS, 732 byte(s) sent to socket
> May 24 06:27:12 copper stunnel: LOG4[1022918]: Possible memory leak at ../crypto/bn/bn_lib.c:224: 30007 allocations
> May 24 06:27:12 copper stunnel: LOG4[1022919]: Possible memory leak at ../crypto/bn/bn_lib.c:224: 30007 allocations