Possible memory leak at asn1_lib.c:412: 20417 allocations - stunnel-users

12 Apr 2019

Hi,
I'm using stunnel version 5.44 with OpenSSL version 1.0.2r on Linux. I
noticed if stunnel has been running for a while, we start observing
these messages in the logs:
Apr 12 19:12:11 localhost stunnel: LOG4[971]: Possible memory leak at
asn1_lib.c:412: 20417 allocations
Apr 12 19:12:11 localhost stunnel: LOG4[971]: Possible memory leak at
tasn_new.c:180: 20416 allocations
And indeed, the process is consuming memory at a steady rate, and
continues to grow until stopped. I updated to the latest stunnel
version (5.53) and I no longer see these "possible memory leak"
messages in the logs, yet the process still appears to consume memory
as before (until it gets very large and things stop working).
Is this actually a bug in the OpenSSL library? I'm using the latest in
that release series (1.0.2), but perhaps this is a "known" leak and
resolved in OpenSSL 1.1.1?
Any help would be greatly appreciated.
Thanks,
Marc