spamprobe crashes on train and cleanup operations

this just startted happening after upgrading from bionic to focal.

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I copied my database out of the way and created a new one to see if that helped. Working it through a corpus of my saved mail with train-good and this brand-new empty database, I see that it is not crashing on every run, only some of them.
I do not know yet if there is a pattern to when it does and does not crash, the count of emails it will and will not train-good on is not at all consistent.

I'm unsure, but this may be related to https://bugs.launchpad.net/ubuntu/+source/spamprobe/+bug/1882418

Those messages may contain images, can you try the patch I just posted at https://bugs.launchpad.net/ubuntu/+source/spamprobe/+bug/1882418 and see if that corrects the issue?

Looking at the attached core dump, it seems that this is in fact the same bug as 1882418, as the back trace shows it crashing when parsing a jpg image in the affected routine. Hopefully, Luke Schierer can confirm with the source emails, but I would consider this bug a duplicate-of-1882418.

I'm not quite sure how to build a replacement deb with the patch?

I'm not up on naming conventions, but here is a "build 2p" that can be installed with dpkg -i. To avoid dependency issues, I would install the maintained version of spamprobe and then install this on top of it. To revert, simply remove and then reinstall the maintained version.

Example:

$ sudo apt install spamprobe

$ (RUN YOUR TEST... should fail)

$ sudo dpkg -i spamprobe_1.4d-14build2p_amd64.deb

$ (RE-RUN Test ... should pass)

To revert:

$ sudo apt remove spamprobe
$ sudo apt install spamprobe