SSL_read error on multiple simultaneous upstream SSL downloads

[Maxim Dounin]

Hello!

On Fri, Oct 18, 2013 at 07:59:40PM +0000, Agent Coulson wrote:

> Yes, I am able to reproduce this talking to the same nginx as an upstream,
> here is my new config.  To reproduce, create a file in the root which is
> several Mb, i used 20Mb, and issus multiple simultaneous curl's to the
> object, i found rate-limiting my curl is the best way to repro.  This
> suggests there is some problem when we have to buffer.  I'm skeptical that
> this is an openssl issue as I have used multiple different openssl versions
> and still run into this.  However for completeness, I've reprod with
> openssl sources from openssl.org (openssl-1.0.1e) as you suggested.

[...]

Ok, I was able to reproduce this.

Looks like a regression in OpenSSL 1.0.0+.  I'm able to reporduce 
the problem with OpenSSL 1.0.0 and more recent versions, including 
recent git snapshot, but everything is fine with OpenSSL 0.9.8y 
and previous versions.

Bisection on OpenSSL 1.0.0 branch may be a helpful to trace the 
exact cause.

-- 
Maxim Dounin
http://nginx.org/en/donation.html