mod_mem_cache pool lifetime problem

[Eric Covener <co...@gmail.com>]

http://issues.apache.org/bugzilla/show_bug.cgi?id=41551

mod_mem_cache retains pointers to short-lived (r->pool) storage in its
much longer lived cache by way of calling apr_table_copy on the
response headers.  This causes the response headers of
served-from-the-cache respones to point to undefined data.

Current code properly leads to a failed assertion with pool debugging
enabled -- I attached a simple patch to the bug report that does a
deep copy of the response headers before they are stored away in the
cache. This remedied the APR_POOL_DEBUG assertion as well as some
obvious Last-Modified and ETag corruptions I saw.

In 2.0.x mod_mem_cache uses the heap directly, so this is only an issue in
2.2.x/trunk

-- 
Eric Covener
covener@gmail.com