weird anchor bug

Jonathan Dance jd at
Sat Oct 28 02:12:45 MSD 2006


This is a bug that occurs in IE6 that causes certain backends
(mongrel/Rails in this case) to die unexpectedly:

Current behavior:

1. A user visits a Rails page in Internet Explorer 6 - certain
versions of IE6 may not have this bug but we were able to reproduce it
on the majority of our Windows machines.

2. That page returns a "Location" header with an anchor, e.g.:


3. As a result, IE sends a request as follows:

etc etc

This is a bug in IE - it should have stripped the #zap from the URL
but it does not. If the URL is refreshed, IE correctly removes the
anchor before sending it to the server.

4. Upon receiving the request, a "403 Bad Gateway" error occurs
because the mongrel process bails.

Expected behavior:

Because this bug could affect a large number of backends
(cgi/fastcgi/proxy), nginx should remove the anchor part of the URL
before passing it on to any other service.

I will also be passing this on to the mongrel guys.


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