Re: could not send data to client: Permission denied

Daniel Jakots <postgres@chown.me> writes:
> On Thu, 27 Aug 2020 09:04:25 -0700, Adrian Klaver
> <adrian.klaver@aklaver.com> wrote:
>> Are you using some sort of authentication for the API?

> Sorry I'm not sure what you mean?

> Between the clients and the python code I use some "basic auth" (and IP
> restrictions on the reverse proxy). But I can't see how it would cause
> the problem.

The error shows that you're already through authentication and executing a
normal query (since a query is cited in the log).  So whatever this is,
it doesn't seem like it could be an authentication issue.

It looks like send() itself is returning EACCES, which seems just
weird.  The send(2) man page does cite some possible causes of
EACCES, but none of them seem relevant here.  I think you might
need a kernel guru.

            regards, tom lane