Bug 43668

Summary: ApplicationDispatcher.doForward for non-HTTP request is always NULL
Product: Tomcat 6 Reporter: Mailmur <mailmur>
Component: CatalinaAssignee: Tomcat Developers Mailing List <dev>
Status: RESOLVED FIXED    
Severity: critical    
Priority: P2    
Version: 6.0.14   
Target Milestone: default   
Hardware: Other   
OS: other   
Attachments: Patch against 6.0 trunk to fix this

Description Mailmur 2007-10-21 13:16:07 UTC 
This applies to both 6.x and 5.5x version !!

Tomcat6.x
http://svn.apache.org/repos/asf/tomcat/tc6.0.x/trunk/java/org/apache/catalina/core/ApplicationDispatcher.java

Tomcat5.5.x
http://svn.apache.org/repos/asf/tomcat/container/tc5.5.x/catalina/src/share/org/apache/catalina/core/ApplicationDispatcher.java

There is a severe always-NULL case in both T6.x and T5.5x sources if request is
non-HTTP forward. processRequest(req, res, state) method should use the original
"request" and "response" objects, but it gives "hrequest" and "hresponse" objects.

private void doForward(ServletRequest request, ServletResponse response) {
   ...continue...
  // Identify the HTTP-specific request and response objects (if any)
  HttpServletRequest hrequest = null;
  if (request instanceof HttpServletRequest)
     hrequest = (HttpServletRequest) request;
  HttpServletResponse hresponse = null;
  if (response instanceof HttpServletResponse)
     hresponse = (HttpServletResponse) response;

   // Handle a non-HTTP forward by passing the existing request/response
   if ((hrequest == null) || (hresponse == null)) {
      processRequest(hrequest,hresponse,state);
   }
   ...continue...
}

Calling program gets a NPE exception when forwarding a request.
java.lang.NullPointerException at 
org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:459)
Comment 1 william.barker 2007-10-21 19:30:53 UTC 
Created attachment 21017 [details]
Patch against 6.0 trunk to fix this

This handles the case where the outer most wrapper is a ServletRequestWrapper,
but not a HttpServletRequestWrapper.  This further breaks 39417, but that one
is invalid anyway (according to the spec).
Comment 2 Mailmur 2007-10-22 06:36:09 UTC 
39417: ApplicationDispatcher.unwrapRequest() should not assume servletRequestWrapper
http://issues.apache.org/bugzilla/show_bug.cgi?id=39417

What do you mean, is it that a bug 39417 is even further away to be fixed?
I made a quick test and posted a solution I used, a simple is-instanceof check
and bail out. Fix is posted at the end of 39417 report.
Comment 3 william.barker 2007-10-25 20:10:11 UTC 
Fixed in the next 6.0 release with the attached patch.