Dear Maintainer,

Upon upgrading from buster to bullseye this weekend, which included
libsnmp-perl going from 5.7.3 to 5.9, we noticed that one of our Perl
scripts utilising SNMP started segfaulting. Stacktraces[0] indicate
similar behaviour to what Steinar H. Gunderson described in his
do_not_callback_for_failed_reports patch.[1] Looking at the source tree,
it appears this patch was commented out just after 5.8 was released,[2]
presumably due to this upstream refactor of the receive API.[3] My
knowledge of both C and SNMP is unfortunately too lacking for it to be
apparent to me what would need to change to make it possible to reapply
the patch to the refactored functions. Any ideas on how to proceed?

All the best,
Ole Peder Brandtzæg

P.S. This is my time reporting a bug with a Debian package – do let me
know if I've done something wrong or you require additional information!

[0]: https://pastebin.com/366kWZNS
[1]: https://marc.info/?l=net-snmp-coders&m=141374910528458&w=3
[2]:
https://salsa.debian.org/debian/net-snmp/-/commit/20442f3b7a0410f5da27399017436c623c705415?page=2
[3]:
https://github.com/net-snmp/net-snmp/commit/a9ce31c4b8187aea07a648cf115e956159ac072e

Hi Ole,
  It looks like that offending code wasn't removed, it was just
relocated further along [1].
Looking at what they have done for net-snmp 5.9.2 snmplib/snmp_api.c
isn't changed between 5.9 and 5.9.2 so I'll apply it as the problem
isn't going away.

Your bug report was fine BTW. If there was an easy proof of concept
that is even better but this looks like its a timing issue with
delayed responses. The information helped get a resolution for me
pretty quickly.

 - Craig

1: https://github.com/net-snmp/net-snmp/blob/V5-9-patches/snmplib/snmp_api.c#L5772

Ah, my bad! All the indentation differences in the original patch made
it unclear to me what it actually did…

Wonderful, thanks a bunch. I presume this won't land in stable anytime
soon though, right, but maybe in backports?

All the best,
Ole

Hello,

Bug #1011440 in net-snmp reported by you has been fixed in the
Git repository and is awaiting an upload. You can see the commit
message below and you can check the diff of the fix at:

https://salsa.debian.org/debian/net-snmp/-/commit/f9d29807d65d66c35bb640a72e147f01bbb44d15

(this message was generated automatically)
-- 
Greetings

https://bugs.debian.org/1011440

We believe that the bug you reported is fixed in the latest version of
net-snmp, which is due to be installed in the Debian FTP archive.

A summary of the changes between this version and the previous one is
attached.

Thank you for reporting the bug, which will now be closed.  If you
have further comments please address them to 1011440@bugs.debian.org,
and the maintainer will reopen the bug report if appropriate.

Debian distribution maintenance software
pp.
Craig Small <csmall@debian.org> (supplier of updated net-snmp package)

(This message was generated automatically at their request; if you
believe that there is a problem with it please contact the archive
administrators by mailing ftpmaster@ftp-master.debian.org)
Format: 1.8
Date: Wed, 25 May 2022 22:09:23 +1000
Source: net-snmp
Architecture: source
Version: 5.9.1+dfsg-2
Distribution: unstable
Urgency: medium
Maintainer: Debian SNMP Team <team+snmp@tracker.debian.org>
Changed-By: Craig Small <csmall@debian.org>
Closes: 997895 998152 1011440
Changes:
 net-snmp (5.9.1+dfsg-2) unstable; urgency=medium
 .
   * Fix path for net-snmp-create-v3-user Closes: #997895
   * Use pidof for net-snmp-create-v3-user so don't need procps
   * Make snmpd.conf group readable Closes: #998152
   * Reapplied perl callback patch Closes: #1011440
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