It's always best, imo, to follow-up with a bugzilla entry with
description and patch.

Thx!!
On Mar 19, 2014, at 3:58 PM, Micha Lenk <[email protected]> wrote:

> Hi Apache developers,
> 
> next is a bug that causes mod_proxy_html to add some random characters (+html 
> code) to HTML pages, if the document is smaller than 4 bytes. (Thomas, Ewald, 
> this is issue #18378 in our Mantis). It looks like the output is from some 
> kind of uninitialized memory. The added string sometimes matches part of a 
> previously delivered request. Also, it looks like this only happens when 
> doing multiple HTTP requests with the same browser and using HTTP Keep Alive.
> 
> The root cause is that the charset guessing with xml2enc needs to consume at 
> least 4 bytes from the document to come to a conclusion. The consumed bytes 
> are buffered so that they can later get prepended to the output again. But 
> apparently it is assumed that there are always at least 4 bytes available, 
> which in some cases is not the case. In these cases the buffer may contain 
> some bytes left behind from the previous request on the same connection.
> 
> The attached patch fixes that issue by simply skipping documents smaller than 
> 4 bytes. The rationale behind this is, that for HTML rewriting to do 
> something useful, it needs to work on an absolute URL (i.e. including a 
> schema). But as the schema "http" is already 4 bytes, there would be nothing 
> to rewrite.
> 
> The patch is based on httpd trunk, rev. 1579365.
> 
> Please provide feedback whether I should file an issue in Apaches Bugzilla or 
> whether this isn't needed in this case.
> 
> Regards,
> Micha
> <modproxyhtml_skip_too_small_documents.patch>

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