From: Tom Lane <tgl@sss.pgh.pa.us>
To: Stephen Frost <sfrost@snowman.net>
cc: Peter <pmc@citylink.dinoex.sub.org>, pgsql-hackers@lists.postgresql.org
Subject: Re: 12.1 not useable: clientlib fails after a dozen queries (GSSAPI
 ?)
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Comments: In-reply-to Stephen Frost <sfrost@snowman.net>
	message dated "Fri, 10 Jan 2020 15:38:07 -0500"
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Date: Fri, 10 Jan 2020 15:58:10 -0500
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Stephen Frost <sfrost@snowman.net> writes:
> Ah-hah.  Not sure if that was Robbie or myself (probably me, really,
> since I rewrote a great deal of that code).  I agree that the regression
> tests don't test with very much data, but I tested pushing quite a bit
> of data through and didn't see any issues with my testing.  Apparently I
> was getting pretty lucky. :/

You were *very* lucky, because this code is absolutely full of mistakes
related to incomplete reads, inadequate or outright wrong error handling,
etc.

I was nearly done cleaning that up, when it sank into me that
fe-secure-gssapi.c uses static buffers for partially-read or
partially-encoded data.  That means that any client trying to use
multiple GSSAPI-encrypted connections is very likely to see breakage
due to different connections trying to use the same buffers concurrently.
I wonder whether that doesn't explain the complaints mentioned upthread
from the Ruby folks.

(be-secure-gssapi.c is coded identically, but there it's OK since
any backend only has one client connection to deal with.)

>> I'll have a patch in a little while.

> That's fantastic, thanks!

This is gonna take longer than I thought.

			regards, tom lane